Title of Invention

AN APPARATUS FOR TREATING TISSUE OF THE PROSTATE.

Abstract In order to reduce blood flow thereby accumulating additional equivalent thermal dose following the step of heating an organ or appendage by irradiating microwaves at the organ or appendage, the step of compressing the organ or appendage fol- lowine the heating step is added to thertherapy treatment. In a preferred embodiment, the organ is the prostate and periodic prostate compression is employed to reduco the prostate blood flow thereby allowing chemotherapy, thermosensitive liposome-encapsulated chemotherapy, or gene therapy to accumulate in the prostate region during thermotherapy. Doppler ultrasound imaging may be used to measure turmor blood flow rate and then serve as real-time feedback to assist in adjusting the amount of balloon catheter inflation and to assess damage to the tumor VACCUME during the treatment.
Full Text WO 2004/026098 PCT/US2003/028898

METHOD FOR ADMINISTERING THERMOTHERAPY
TO PREVENT THE GROWTH OF TUMORS
Related Applications
5 This application claims priority to US Patent Application No. 10/247,747,
filed September 20, 2002, which is a contimiation-in-part of U,S. Patent
Application No. 09/597,234, filed June 20, 2000,
Background of thc Invention
1, Field of the Invention
10 The present invention generally relates to a system for administering
focused energy to a body selectively using either a single energy applicator or
multiple microwave applicators in order to treat visable tumors and microscopic
malignant and benign cells in prostate tissue with hyperthennia. The system
according to the invention may be used to treat healthy tissue containing
15 undetected microscopic pathologically altered cells (neoplasia) that are of high-
water content to prevent the occurrence of or the recurrence of cancerous, pre-
cancerous or benign prostatic lesions. In addition, the disclosed system and
method for using the system can prevent the growth of tumors inside the prostate,
as well as prevent the spread of cancer cells outside the prostate.
20 2. Description of the Prior Art
In order to treat prostate tumors with, hyperthermia, it is necessary to heat a
significant portion of the prostate gland while sparing healthy tissues in the
prostate as well as the surrounding tissues including the urethral and rectal walls
of a patient. In the United States there arc approximately 200,000 cases of detected
25 prostate cancer annually as well as 375,000 cases of benign prostatic hyperplasia,
known as BPH, (enlarged prostate gland). BPH is a non-cancerous enlargement
(tumor) of the prostate gland that occurs in almost all men as they age, particularly
past the age of 50 years. In the case of BPH, the enlargement of the prostate
involves the excessive growth of tissue that eventually obstructs the bladder outlet,
30 creating difficulties with urination. In the case of prostate cancer, eventually the
cancer will break through the prostate gland capsule leading to the spread of
cancer to the bones and vital organs of the body. Although some of the signs of

WO 2004/026098 PCT7US2003/028898

BPH and prostate cancer are the same, having BPH does not increase the chances
of getting prostate cancer. Nevertheless, a patient who has BPH may have
undetected prostate cancer at the same time or may develop prostate cancer in the
future.
5 As is known in the art, the use of heat to treat prostate tumors can be
effective in a number of ways; however, in most cases, the heat treatment must be
capable of heating a significant volume of the prostate gland without overheating
the urethral and rectal walls. In radiation therapy, the entire prostate and adjacent
tissues are inadiated with x-rays to kill all the microscopic cancer cells. While
10 heating large volumes of the prostate can destroy many or all of the microscopic
carcinoma cells in the prostate, known methods of heating tumors can destroy
healthy tissue in the prostate and, more damaging, in the urethral and rectal walls
of a patient.
The prostate gland has electrical properties similar to muscle (T.S. England
15 and N.A. Sharples, Nature, Vol. 163, March 26,1949, pp. 487-488,) and is known
to have a high-water content, on the order of 80% (FA. Duck, Physical Properties
of Tissue, A Comprehensive Reference Book, Academic Press, New York, p. 321,
1990). Tumor tissue, in general, tends to be 10 to 20% higher in water content
than normal tissue (Foster and Schepps, Journal of Microwave Power, vol. 16,
20 number 2, pp. 107-119, 1991). Thus, prostate tumors may have a water content on
the order of about 90%. Accordingly, selective microwave heating of the prostate
would be the best method of targeting cancerous or benign cells.
It is well known that microwave energy can heat high-water content tumor
tissues faster when compared to the heating that occurs in lower-water content
25 normal tissues. Tumor tissue tends to be poorly perfused so blood flow often
decreases at therapeutic temperatures allowing rapid heating, while in normal
tissues the blood flow often increases protecting the normal healthy tissue from
heat damage. Many clinical studies have established that hyperthermia (elevated
temperature) induced by electromagnetic energy absorption in the microwave
30 band, significantly enhances the effect of radiation therapy in the treatment of
malignant tumors in the human body (Valdagni, et al., International Journal of
Radiation Oncology Biology Physics, Vol. 28, pp. 163-169, 1993; Overgaard et
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al., International Journal of Hyperthermia, Vol. 12, No. 1, pp. 3-20,1996; Vernon
et al., International Journal of Radiation Oncology Biology Physics, Vol. 35, pp.
731-744,1996), Radio-resistant cells such as S-phase cells can be killed directly
by elevated temperature (Hall, Radiobiology for the Radiologist, 4th Edition, JB
5 Lippincott Company, Philadelphia, pp. 262-263, 1994; Perez and Brady,
Principles and Practice of Radiation Oncology, Second Edition JB Lippincott
Company, Philadelphia, pp. 396-397, 1994). Hyperthermia treatments with
microwave radiating devices are usually administered in several treatment
sessions, in which the malignant tumor is heated to about 43° C for about 60
10 minutes. It is known that the amount of time to kill tumor cells decreases by a
factor of two for each degree increase in temperature above about 430 C (Sapareto,
et al., International Journal of Radiation Oncology Biology Physics, Vol. 10, pp.
787-800, 1984). Thus, a 60-minute heat-alone treatment at 43° C can be reduced
to only about 15 minutes at 45° C, which is often referred to as an equivalent dose
15 (t43°C equivalent minutes).
During treatments with noninvasive microwave applicators, it has proven
difficult to heat semi-deep tumors adequately while preventing surrounding
superficial healthy tissues from incurring pain or damage due to undesired hot
spots. The specific absorption rate (SAR) in tissue is a common parameter used to
20 characterize the heating of tissue. The SAR is proportional to the rise in
temperature over a given time interval times the specific heat of the tissue, and for
microwave energy the SAR is also proportional to the electric field squared times
the tissue electrical conductivity. The units of absolute SAR are waits per
kilogram.
25 The first published report describing a non-adaptive phased array for deep
tissue hyperthermia was a theoretical study (von Hippel, et at., Massachusetts
Institute of Technology, Laboratory for Insulation Research, Technical Report 13,
AD-769 843, pp. 16-19, 1973). U.S. Patent No. 3,895,639 to Rodler describes
t wo-channel and four-channel non-adaptive phased array hyperthermia circuits.
30 Likewise, a non-adaptive phased array hypothermia system was disclosedinU.S.
Patent No. 4,589,423 to Turner.
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Bassen et al., Radio Science, Vol. 12, No. 6(5), Nov-Dec 1977, pp, 15-25,
shows that an electric-field probe can be used to measure the electric-field pattern
in tissue, and in particular, shows several examples in which the measured
5 electric-field has a focal peak in the central tissue. This paper also discusses a
concept for real-time measurements of the electric field in living specimens.
However, Bassen et al. did not develop the concept of measuring an electric field
using real-time with an electric-probe to adaptively focus a phased array.
The most difficult aspect of implementing hyperthermia in deep prostatic
10 tissues, with microwave energy, is producing sufficient heating at a predetermined
depth while protecting the urethral and rectal walls and surrounding organs from
bums. Noninvasive multiple applicator adaptive microwave phased arrays with
invasive and noninvasive electric field probes can be used for producing an
adaptively focused beam at the tumor position with adaptive nulls formed in
15 healthy tissues as described in U.S. Pat Nos. 5,251,645, 5,441,532,5,540,737, and
5,810,888 to Fenn, all of which are incorporated herein by reference. Ideally, a
focused microwave radiation beam ia concentrated at the tumor with minimal
energy delivered to sunounding healthy tissue. To control the microwave power
during treatment, a temperature-sensing feedback probe (Samaras et al.,
20 Proceedings of the 2nd International Symposium, Essen, Germany, June 2-4,1977,
Urban & Schwarzenberg, Baltimore, 1978, pp. 131-133) is inserted into the tumor,
however, it is often difficult to accurately place the probe in the tumor. An
additional difficulty occurs in delivering hyperthermia to carcinoma spread
throughout the prostate gland, because of a lack of a well-defined target position
25 for the temperature-sensing feedback probe. In otter situations, it is desirable
simply to avoid inserting probes (either temperature or E-field) into the prostate
tissue in order to reduce the risk of infection or spreading the cancer cells when
the probe passes through the tumor region.
Several articles have been written on the use of dual intracavitary
30 (transurethral and transrectal) coherent phased array microwave applicators for
prostate cancer treatment (A. Surowiec, et al, Hyperfhermic Oncology 1992, Vol.
1, Summary Papers, Proceedings of the 6th International Congress on
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Hyperthermic Oncology, April 27-May 1,1992 (Arizona Board of Regents),
p. 268 (abstract); MM. Yeh, et al Hyperthennic Oncology 1992, Vol. 1,
Summary Papers, Proceedings of the 6th International Congress on Hyperthermic
Oncology, April 27-May 1, 1992 (Arizona Board of Regents), p. 269 (abstract);
5 and J.C. Camart, Hyperthermic Oncology 1996, Vol. 2, Proceedings of the 7th
International Congress on Hyperthermic Oncology, Rome, Italy, April 9-13,1996,
pp. 598-600). Further, US. Patent No, 5,007,437 to Sterzer describes the use of
non-coherent transurethral and transrectal applicators for BPH treatments.
However, the known prior art is directed to the use of transurethral and transrectal
10 applicators for treating solid, tumor masses. None of the known procedures are
concerned with treating microscopic disease and preventing the occurrence of
solid tumor masses such mat occur in cancer and BPH,
Prostate Cancer
The current standard of medical care for treating prostate cancer includes
15 radical or nerve-sparing prostatectomy in which, the entire prostate gland is
surgically removed, and brachytherapy in which radiation seeds at low dose are
permanently implanted in the prostate gland radiating effectively for 6 to 9 months
or radiation seeds at high dose are temporarily implanted in the prostate for about
2 days, combined with external-beam radiation therapy to catch microscopic
20 cancer cells that may have penetrated or could penetrate the prostate capsule. Side
effects from surgery include incontinence and impotence. The cancer recurrence
rate after surgery can be as high as approximately 35% at 5 years, and
approximately 60% at 10 years, particularly when the prostatic-specific antigen
level (discussed below) is greater than 10. Radiation therapy has short-term side
25 effects such as skin reactions, fatigue and nausea. Additional long-term side
effects of radiation therapy to the prostate include urinary incontinence (loss of
bladder control) and impotence, as well as damage to surrounding organs.
Hormone therapy is also used to supplement prostate cancer treatments by
stopping cancer cells from growing. Male hormones, such as testosterone, help
30 cancer cells grow and, in contrast, female hormones or estrogens inhibit growth.
Side effects of estrogen therapy include nausea and vomiting, hot flashes, fluid
retention, weight gain, headaches and gynccomastia (an increase in breast tissue)
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in men.
Fundamentally, the problem with current prostate treatments is the
inability to control microscopic capsule penetration from the prostate gland, which
spreads the cancer to vital organs. Men with microscopic capsule penetration of
5 cancer cells are not cured by radical prostatectomy. These microscopic cells may
spread far from the prostate gland into vital organs by means of the lymphatic
system or by blood vessels through the prostate capsule.
It is possible to detect the presence of prostate cancer by means of the well-
known serum assay Prostate-Specific Antigen (PSA) test (M.K. Brawer, "Prostate-
10 Specific Antigen: Current Status," CA A Cancer Journal for Clinicians Vol. 49,
pp. 264-281, 1999, and J.E Oesterling, "Prostate Specific Antigen: A Critical
Assessment of the Most Useful Tumor Marker for Adenocarcinoma of the
Prostate," The Journal of Urology, Vol. 145, pp. 907-923, May 1991.). The
prostatic lumen contains the highest concentration of PSA in the human body.
15 PSA is an enzyme produced in all types of prostatic tissue (normal, benign
hyperplastic and malignant). In particular, PSA is a serins protease that is
produced only by the epithelial cells lining the acini and ducts of the prostate
gland; none of the other cellular components of the prostate, including the stromal
and vascular elements produce PSA Researchers have verified that PSA is
20 produced in the epithelial cells of BPH tissue, primary prostate cancer tissue, and
metastatic prostate cancer tissue. The serum PSA test detects a significant number
of prostate cancers and the destruction of prostatic tumors leads to reduced PSA
levels, since the body stops producing PSA when the tumors are eliminated.
Currently, a PSA level of 4.0 ng/ml or greater is used to decide whether a patient
25 will be biopsied to try to verify the presence of carcinoma in the prostate. Thus,
patients with a PSA level under 4.0 ng/ml currently are not biopsied even if they
experience the signs and symptoms of prostate cancer which may include: frequent
urination, especially at night, inability to urinate, trouble starting or holding back
urination, a weak or interrupted urine flow and frequent pain or stiffness in the
30 lower back, hips or upper thighs.
In addition to PSA level, the Gleason Grade is used to histologically grade
adenocarcinoma of the prostate (G.k. Zagars, et at, International Journal of
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Radiation Oncology Biology Physics, Vol. 31, No. 2, pp. 237-245, 1995), with
Grade 1 being the least malignant and slowest growing. Gleason Grade 3 is the
most commonly occurring grade when diagnosed. Gleason Grades 4, 5 and above
(up to 10) are considered highly aggressive, rapidly growing carcinomas.
5 Biopsy results and staging are used to predict the behavior of the cancer
and the likelihood of its spread. Stage 1 tumors are small and cannot be felt on
rectal examination. Stage 2 or greater refers to prostates in which the tumor can
be felt. Stage 3 cancers have spread beyond the boarders of the prostate, In Stage
4, which can be determined by imaging studies such as bone scans, CT, or MRI
10 scans, the cancer has spread into nearby lymph glands, the bones, or elsewhere in
the body. As is well known in the medical field, the earlier the cancer is detected,
the better the chance of being a cancer survivor. If detection is not possible before
stage 2, the next best medical option would be to safely treat apparently healthy
tissue. Thus, there is a need to treat healthy tissue since cancer, in general, cannot
15 be detected until it has reached stage 2 or a later stage.
There are four types of prostate ductal carcinomas: transitional cell
carcinoma, intraductal adenocarcinoma, mixed ductal carcinoma, and
endometrioid carcinoma. Transitional cell and mixed ductal carcinomas are
aggressive cancers that require complete removal of the prostate and bladder if
20 found while the tumor is still confined to the prostate. Complete removal of the
prostate and bladder is also the medically accepted treatment for endometrioid
carcinoma. Intraductal adenocarcinomas are treated by radical prostatectomy.
Thus, there is a need for a system for treating and preventing the growth and
spread of cancer that does not require surgical prostatectomy.
25 Benign Prostatic Hyperplasia
Benign Prostatic Hyperplasia (BPH) is described primarily as an
enlargement of the prostate gland that exerts pressure on the urethra, resulting in
obstruction of the flow of urine, and is a common affliction in middle-aged and
older males. Approximately 50% of men older than 65 years will have BPH
30 symptoms that significantly affect their quality of life. The American Urological
Association (AUA) Symptom Index was developed to help categorize BPH
symptoms. The AUA score has the following score ranges: 0 to 7 points - BPH
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symptoms are considered mild; 8 to 19 points - BPH symptoms are considered
moderate; and 20 to 35 points - BPH symptoms are considered severe. However,
many BPH patients do not seek treatment until their AUA score is about 12.
Over the last two decades, a number of treatments for BPH have been
5 developed each with advantages and disadvantages. The major types of BPH
treatment systems are; 1) transurethral resection of the prostate (TURP), 2)
Transurethral Electrovaporization of the Prostate (TVP), 3) Drugs, 4) Interstitial
Laser Coagulation, 5) RF Needle Ablation, and 6) Microwave Thermotherapy of
the Prostate. Other treatment techniques have been explored, including
10 transurethral incision of the prostate, prostatic stents, and balloon dilation, but are
used to a lesser extent,
BPH treatment success and practicality can measured in terms of 1)
efficacy, 2) durability, 3) level of pain (during and after the procedute), 4)
recovery period, 5) complexity of the procedure, 6) cost of the procedure, and 7)
15 side effects. Efficacy of BPH treatments is commonly quantified using the AUA
Symptom Index (SI) and peak urine flow rate. Normal urine flow rate is about 16
ml/sec. Other optional tests such as residual urine volume and pressure flow are
sometimes used to judge efficacy. Durability is the length of time for which the
treatment is effective. The level of pain relates primarily to the need for either
20 general anesthesia or local anesthesia. The recovery period is measured in terms
of the number of days of hospitalization and home rest. The complexity of the
procedure is a function of the length of the procedure, the training of the
individual administering the procedure (either an urologist or a technician), the
type of anesthesia, required, and the length of time needed for Foley catheterization
25 after treatment. The cost of the procedure is influenced strongly by the length and
complexity of the procedure - particularly whether a hospital stay is required.
Until about 1990, the major treatment ("Gold Standard") for BPH was
Transurethral Resection of the Prostate (TURP) which is administered by
urologists. TURP is expensive, requires a long recovery time, and has a number
30 of significant side effects, which has prompted the search for better treatment
techniques. A summary of approaches to treat BPH, including surgery, drug and
laser, RF, and microwave applications is described below.
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Transurethral Resection of the Prostate (TURP):
The "Gold Standard" of BPH treatments involves a surgical procedure in
which a rigid transurethral scope with an electrosurgical loop is used to remove
part of the enlarged prostate tissue (primarily the central zone of the prostate) with
5 RF energy, In practice, 90% of surgical procedures for BPH involve TURP, due
to its excellent efficacy (85% or more), long-term durability (10 to 15 years) for
90% of patients. On the order of 200,000 TURPs are performed in the United
States annually. TURP has a number of drawbacks: It is a very painful procedure
and requires both 2-4 days of hospitalizaaon and 2-4 weeks of recovery at home.
10 The TURP procedure is performed in about one hour and requires general
anesthesia. An urologist must perform the procedure. A Foley catheter is required
for about 2-3 days post treatment. some of the major potential side effects of a
TURP include impotence, incontinence, high blood loss, and retrograde
ejaculation.
15 Open Prostatectomy:
An open, prostatectomy is primarily used on patients with very large
prostates with excellent results: the efficacy is greater than 95% and the durability
is the same as TURP (10 to 15 years), With any surgical procedure, the pain level
is very high and general anesthesia is required. About 7 to 10 days of
20 hospitalization is required with an additional 3-5 weeks spent at home. The
procedure takes a few hours and must be performed by a urologist. Following the
treatment, a Foley catheter must be used for 2-4 days to drain the bladder. An
open prostatectomy is about twice the cost of a TURP, and has the serious
potential side effects and complications including high blood loss, impotence, and
25 incontinence,
Transurethral Electrovaporization_of the_Prostate (TVP):
Basically a modification of TURP, transurethral electro vaporization of the
prostate employs a grooved electrosurgical rollerball electrode to channel open the
urethra that is blocked by the prostate tissue. The TVP procedure is safer and has
30 minimal side effects compared to TURP, The efficacy is excellent (85%), but still
is a very painful procedure requiring 2-4 days of hospitalization and 1-2 weeks at
home, A urologist performs this 60-minute procedure and the patient is under a
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general anesthetic. A Foley catheter must be used for 2-4 days following this
procedure. The procedure costs slightly less than TURP. There is less blood loss
than with TURP, but their are still the potential side effects of impotence,
incontinence, and retrograde ejaculation.
5 Transurethral Incision of the Prostate (TUIP):
In a relatively new procedure for patients with small prostates,
transurethral incision of the prostate provides an efficacy of about 80%. However,
TUIP is not effective on large prostates, A minimal amount of prostate tissue is
removed in this procedure - a simple incision is made along the entire length of
10 the prostate. The TUIP procedure allows the bladder neck to spring open,
allowing free urinary flow. The durability is expected to be similar to TURP, but
clinical research is still in progress. This procedure is moderately painful and
requires only a day or two of hospitalization, or for some patients is an outpatient
procedure. Usually, 4 to 7 days of home rest are needed following the procedure.
15 A urologist must perform this 60-mimite surgical procedure and a Foley catheter
must be used for 2 to 4 days. The cost of the TUIP is about the same as TURP.
There is less blood loss with this procedure compared to TURP, but there are still
the potential side effects of impotence, incontinence, and retrograde ejaculation.
Balloon Dilation:
20 For patients with small prostates, balloon dilation within the prostatic
urethra can be used to offer some relief from BPH symptoms. The efficacy is only
about 60% and the durability is only 1 to 5 years. This procedure is less costly
than TURP and is usually performed as an outpatient with several days of home
rest The procedure is performed under local anesthesia by a urologist in about 30
25 minutes. A Foley catheter is required for about 2-4 days. There may be some
bleeding in this procedure and there are the possible side effects of infection and
impotence. The procedure does not work well on large prostates.
Stents:
For very ill patients with small prostates, stents can be used with good
30 effectiveness to improve BPH symptoms. Durability is not a major issue since
these patients are usually very ill with other diseases. This procedure is moderately
painful and requires only local anesthesia, is performed in about 30-minutes by a
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urologist, and is done as an outpatient with about 4-5 days of home rest. The cost
of this procedure is less costly than TURP. Some of the potential side effects are
irritation, infection, and the formation of debris on the stent.
Drugs:
5 Two categories of drugs are used in treating BPH, One category uses an
alpha blocker (Hytrin or Cardura) to relax the muscles that surround the prostate to
allow better urinary flow, The other type of drug is reductase inhibitor (Proscar)
which actually shrinks the prostate gland.
Hytrin, for example, has very good efficacy (74%) and offers some immediate
10 relief of BPH symptoms, however 2-3 weeks are needed until the full
effectiveness is reached. Clinical data suggests that this drug has at least 3 to 5
years durability and is simply prescribed by a general practitioner. The cost is less
than TURP depending on the number of years of treatment. There can be some
serious side effects such as dizziness, chest pain, irregular heartbeat, and shortness
15 of breath.
Proscar worts well on large prostates, but is ineffective on small prostates.
Full effectiveness of the drug takes about 3 to 6 months and the durability is
estimated at least 3 to 5 years. This drug is prescribed by a general practitioner
and must be taken for at least 12 months. The cost of the drug is less than TURP.
20 Some of the known side effects are impotence, swollen lips, decreased volume of
ejaculate, and skin rash.
Interstitial Laser Coagulation:
Here, an interstitial laser coagulation surgical device delivers laser energy
radially along the length of a custom-designed light diffuser. The diffuser
25 produces an ellipsoidal pattern of thermal damage, applying the laser energy
omnidirectionally and uniformly, to maximize treated tissue volume in the
prostate. This is a moderately painful surgical procedure, requiring one or two
days in the hospital and then 1 to 2 weeks al home. This 30-minute procedure
must be performed by a urologist, with a choice of either general or local
30 anesthesia depending on the patient's condition. A serious disadvantage with this
procedure is the lengthy required time of 1 to 2 weeks in which a Foley catheter
must be used to drain the bladder of urine. The cost of the procedure is less than
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TURP. There are many potential side effects from this treatment including
impotence, incontinence, blood loss, and retrograde ejaculation.
RF Needle Ablation (TransurethraJ Needle Ablation):
This system uses two high-energy RF (approximately 0,47 MHz) needles
5 that are inserted through the urethra into the prostate, to ablate the prostate tissue
in a few minutes. More than 10,000 patients worldwide have been treated with this
system, which provides good to very good efficacy. There is only limited 12-
month durability data for this system, so the long-term effectiveness is not known.
The procedure is moderately painful (local anesthesia required) and is performed
10 as an outpatient with 1-2 weeks for home recovery. The procedure is usually
per formed by a urologist in about 30 minutes- About 40% of patients will require a
Foley catheter for about 2 to 3 days. The procedure costs less than TURP. The
major side effects from this procedure are irritating voiding, erectile dysfunction,
and retrograde ejaculation.
15 In view of the known treatments for BPH, which require costly, painful,
surgery or drugs which have potentially dangerous side effects, there is a need for
a system of treating benign prostatic hyperplasia (BPH) that is not painful; can be
accomplished on an outpatient basis; and quickly restores the patient to his normal
functions. In addition, a method is needed that can safely treat the prosteate gland
20 with focussed energy before a significant amount of microscopic tumor cells form
in the prostate
Summary of the Invention
The above problems associated with known treatments are solved by the
system and method for using the system according to the invention. The system
25 and method according to the invention safely heat pre-cancerous, cancerous, pre-
benign, and benign conditions of the prostate by heating the prostate gland with
focussed or concentrated energy, such as microwave energy, delivered by either
phase non-coherent or coherent array applicators in the urethra and rectum, or with
interstitial applicators positioned within the prostate. In a non-coherent array,
30 separate microwave oscillators can drive the applicators and there is no common
phase relation. In a phase coherent array (phased array), a single microwave
oscillator can drive multiple applicators with, a common phase relation.
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The Applicants' approach is to treat the prostate gland with focussed
energy, such as microwave energy before a significant amount of microscopic
tumor cells form in the prostate gland. As described above, all past uses of
thermal therapy were used for the treatment of established prostate cancers with
5 moderate to high PSA levels (over 4.0 ng/ml) or for the treatment of moderate to
severe AUA symptom index scores for BPH. The preferred embodiment of this
invention is for the prevention or before detection, or before medical intervention
is required. Thus, the inventive method is for treating prostate cancer when the
PSA level is less than 4.0 ng/ml, or for treating BPH whete BPH symptoms are
10 less than severe or the AUA symptom index score is less than 13. In other words,
the inventive method is to prevent the cancer or BPH from developing into a
significant problem for a patient (i.e., before serious adverse effects occur).
The preferred method of treating a prostate, according to the invention, is
with a coherent adaptive phased array and comprises the steps of monitoring
15 temperatures of walls of the urethra and rectum, orienting two microwave
applicators in at least one of the urethra and rectum, adjusting the microwave
power to be delivered to the prostate based on the monitored urethral and rectal
wall temperatures, monitoring the microwave energy dose delivered to the prostate
being treated and automatically completing the treatment when a desired total
20 microwave energy dose has been delivered by the microwave applicators.
Incoherent-array or non-adaptive phased array hyperthermia treatment
systems can be used to heat semi-deep and deep tissue, depending on the radiating
frequency. Due to the dielectric heating of high-water content tissue such as
prostate tumor, it may be possible to safely heat prostate tumors with cither non-
25 coherent arrays or non-adaptive phased arrays.
Moreover, the system and method according to the invention have
application in situations where there is no well-defined position to place the
temperature feedback sensor, or where it is desirable to avoid inserting a
temperature probe into the prostate tissue. In the case of a single applicator, an E-
30 field probe (or E- field sensors) is not necessary and thus, an invasive probe is not
required in the preferred system and method according to the invention. The
inventive system and method may destroy all of the prostate pre-cancerous and
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cancerous cells or benign lesions with heat generated by the focussed energy
thereby avoiding further progression of the cancer cells or benign lesions.
In addition the method according to the invention can he used to enhance
radiation therapy or for targeted drug delivery and/or targeted gene therapy
5 delivery with or without thermosensitive liposomes as described in U.S. Pat. No.
5,810,888 to Fenn.
The method according to the invention destroys the pre-cancerous,
cancerous, pre-benign, and benign cells in the prostate while preserving normal
prostate tissue. Thus, the system and method according to the invention achieves
10 a thermal prostatectomy and avoids damage to healthy tissue; Accordingly, the
inventive method is a prostate conservation technique.
The urethral and rectal wall temperature can be measured by temperature
probe sensors positioned away from the transurethral and transrectal applicators to
obtain the true temperature of the urethral and rectal walls. Alternatively, the
15 tissue temperatures can be monitored by external means, including infrared, laser,
ultrasound, electrical impedance tomography, magnetic resonance imaging, and
radiometry techniques as known in the art.
Alternatively, a temperature probe could be inserted at an appropriate
depth in the prostate tissue to monitor the temperature thereof. As discussed
20 below, insertion of a temperature probe is not a preferred embodiment.
in an embodiment with two or more energy applicators, an invasive E-field
probe, inserted in the prostate, may or may not be used to measure the microwave
power delivered to the tissue to be treated to determine the length of the focussed
energy treatment in a preferred embodiment, the invasive E-field probe can be
25 used to focus the applied energy at the E-field probe inserted in the prostate.
As an alternate embodiment, for a coherent phased array, two E-field
sensors can be placed in the prostatic urethra and rectum non-invasively and be
used to null the E-field in the urethra and rectum and effectively focus the
microwave radiation in the prostate tissue. Additionally, the microwave phase for
30 the transurethral and transrectal applicators can be adjusted so that the microwave
energy is scanned across an area of the prostate,
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The system and method according to the invention can be achieved with or
without compression of the prostate. In a preferred method, a patient's prostate
would be compressed by expanding at least one of a urethral balloon and a rectal
balloon, Focussed energy and prostate compression provide preferential heating
5 of high-water content prostate carcinoma and benign cells in the prostate
compared to the surrounding lower-water content normal prostate tissues and.
tissue surrounding the prostate.
To coherently focus the energy, such as microwave energy, in the prostate,
the patient's prostate can be compressed via a urethral and rectal balloon and
10 means for determining where to focus the energy in the patient's prostate is used.
The means for determining where to focus the energy can be either a single
electric-field probe, inserted in the central portion of the prostate, or two
noninvasive electric-field sensors on the urethral and rectal walls. The probe or
sensors receive signals that can be used to measure a feedback signal in order to
15 adjust the energy phase delivered to the applicators located in the urethra and in
the rectum.
In accordance with another embodiment of the invention, the step of
compressing the prostate may be maintained following the completion of the
microwave-induced heating step. That is, the compression of the prostate is
20 maintained for a period of time following the microwave-induced heating step to
reduce prostate blood flow and to accumulate additional equivalent thermal dose.
The prostate compression can be achieved by maintaining the inflated pressure of
balloon catheters in at least one of the urethral and rectal areas. Periodic prostate
compression to reduce prostate blood flow may be employed .in accumulating
25 chemotherapy, thermosensitive liposome-encapsulated chemotherapy, or gene
therapy in the prostate region during thermotherapy.
The major advantages offered by treatment according to the system and
method of the invention over known treatments are listed below:
1. Prevention and destruction of prostate tumors (including cancerous and
30 0 benign);
2. Immediate relief from any BPH symptoms that might exist;
3. Long term durability;
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4. Only low level pain may be experienced;
5. Outpatient procedure;
6. Local anesthesia;
7, No Foley catheter required; and
5 8. No significant side effects or complications.
A biological stent can be formed in the prostatic urethra due to the
combination of compression balloon dilation, and microwave heat (microwave
urethroplasty) as evidenced in clinical tests held by the assignee, Celsion
Corporation, during 1999. As a result, one of the major deficiencies in known
10 BFH treatments, namely the need for a Foley catheter for several days, is no longer
needed and a patient may experience immediate relief from BPH symptoms.
As described below, applicants' inventive system and method involves
monitoring the microwave energy dose delivered to the prostate being treated and
completing the treatment based on. the total microwave energy dose that has been
15 received. That is, conventional temperature feedback measurements of tumor
thermal dose can be replaced with the total microwave energy delivered to the
coherent phased array or non-coherent microwave applicators and then to the
treated area. Accordingly, with the instant invention, instead of temperature
feedback measurements, which require the insertion of a temperature feedback
20 probe into the prostate and its inherent problems, microwave energy dose is used
as a feedback to determine the required length of treatment. In this application the
term "microwave energy dose" (in Joules or watt-seconds) is similar to the dose
used in radiation therapy, namely the radiation absorbed dose
(Rad) which is a unit of absorbed dose of radiation defined as deposition of 100
25 ergs of energy per gram of tissue.
Thus, the instant method for selectively heating cancerous and benign
conditions of the prostate avoids the risk of spreading cancer cells since the
temperature probe is not inserted into the treated area (tumor bed) of the prostate.
The elimination of an inserted temperature probe reduces the risk of infection to a
30 patient as a result of the inserted probe. Likewise, the microwave field applied to
a tumor would not be subjected to scattering or other disturbance caused by a
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WO 2004/026098 PCT/US2003/028898

temperature probe, especially a metallic probe- In addition, the time and costs
associated with inserting the temperature probe are saved.
The inventive system and method may also be used to treat healthy
prostate tissue or undetected high-water content microscopic pre-cancerous or pre-
5 benign cells in seemingly healthy prostate tissue to present the occurrence of or
recurrence of cancerous conditions of the prostate. Thus, the system and method
according to the invention would be able to destroy or ablate'microscopic
precancerous or pre-benign cells in the prostate gland that are higher in water
content (e.g., 90%) than the prostate gland (e.g., 80%) before they are detected.
10 This would be an early treatment that could prevent cancer from growing in the
prostate and spreading from the prostate, or enlargement of the prostate gland. In
the case of seemingly healthy tissue, the prostate tissue would be irradiated with
microwave energy focused at high-water content microscopic cells that are known
to form lesions without damaging the healthy lower-water content prostate tissue.
15 If both transurethral and transrectal applicators are used and both are
expanded by respective balloons, a preferred system having means for
compressing and immobilizing the prostate to reduce the tissue penetration depth
and to reduce the prostate blood flow is achieved.
In an alternate method, the prostate is compressed with a single
20 transurethral balloon, which immobilizes the prostate tissue, reduces blood flow,
and reduces the penetration depth required for the microwave radiation. The
compression balloon is made of a microwave transparent plastic material such as
Latex. The placement of an E-field feedback probe in the prostate may be
achieved with an ultrasound transducer or other type of image guidance. Further
25 reduction in blood flow can be achieved, in a preferred method, by injecting a
local anaesthetic lidocaine with ephinephrine or anti-angiogenesis drug in the
prostate.
Two microwave applicators (such as described by U.S. Pat. No; 5,007,437
to Sterzer which is incorporated herein by reference) can be positioned
30 transurethrally and transrectally. A phased array can be achieved with a multiple
number of applicators greater man or equal to two. In a preferred embodiment,
coherent 915 MHz microwave power is delivered to the two traosurethral and
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transrectal applicators, at a predetermined power level, whiie phase shifters in
each, channel are adjusted to maximize and focus the microwave energy at the E-
field probe sensor. Water-cooling within the catheters and balloons allows cooling
of the urethral and. rectal walls. Additional interstitial applicators can. be inserted
5 within the prostate to supplement the beating that is produced by the transurethral
and transrectal applicators.
During the hyperthermia treatment, the microwave power level delivered
to each of the applicators may be adjusted either manually or automatically to
avoid high temperatures that could, cause bums or blisters to the urethral or rectal
10 walls. In addition, the amount of prostate compression, if used, is adjusted as
necessary during treatment to provide patient comfort. Each time the prostate
compression is adjusted, the microwave-energy/phasod array is refceused so that
the E-field probe sensor receives maximum power. The total microwave energy,
since the start of the treatment, delivered to the microwave applicators is
15 monitored during the treatment. The treatment is completed when a desired
amount of total microwave energy is delivered to the microwave applicators,
which indicates that the lesion cells are significantly destroyed (i.e., thermal
downsizing) or completely destroyed (i.e., thermal prostatectomy).
In order to determine the effectiveness of the treatment, the prostate tissue
20 may be imaged and examined with one of x-ray, ultrasound, and magnetic
resonance imaging before and after the microwave total energy dose is
administered, as well as with pathological results from needle biopsy of the
prostate tissues.
In an alternate embodiment of the invention, the single invasive E-ficld
25 probe is replaced with two E-field sensors positioned in the urethra and rectum
and the coherent array is phase focused by minimizing (nulling) the individual or
combined power received by the two sensors, providing a completely noninvasive
treatment. In a preferred embodiment, the two E-field sensors are contained with
catheters attached to the outside surface of a compression balloon which provides
30 a pressure contact to the uretbal and rectal walls. Algorithms are used in
conjunction with the feedback signals sensed by the E-field sensors to null areas
on the urethral and rectal walls outside thereby focussing the applied energy on an
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internal site. After the nulling algorithm is completed, the E-field sensors can be
withdrawn and temperature sensors can be inserted to measure the urethal and
rectal wall temperatures.
Such a totally non-invasive hyperthermia treatment where E-field sensors
5 and temperature sensors monitor the urethral and rectal walls would provide an
effective method of destroying benign and cancerous lesions in the prostate. In an
embodiment with non-coherent applicators, an E-fleld focussing probe and phase
shifters are not required to heat the tissue. With, non-coherent energy, only the
applicator radiated power is additive and phase shift is not used.
10 While the preferred embodiment is described with reference to adaptive
microwave phased array technology, Applicants' system and method may be
achieved by focussing energy, in general, to heat and ablate an area of tissue. The
focused energy may include electromagnetic waves, ultrasound waves or waves at
radio frequency. That is, applicants' inventive system and method includes any
15 energy that can be focused to heat and ablate an area of tissue. This energy, such
as microwave or ultrasound energy, can be coherent or non-coherent. In another
embodiment, the energy may come from a fluid or a laser applicator.
In yet another embodiment of the invention with a coherent phased array,
the boundary of an area of tissue to be treated in a body (e.g., prostate) is
20 calculated, an E-field probe may be inserted in the body or at least two E-field
sensors are positioned within the urethra and rectum; and energy is applied
through applicators to the area to be treated. In this embodiment, the focus of the
energy would change so that the focus scans the area to be treated. That is, there is
no longer a fixed focus spot as the relative phase of the applied energy would be
25 adjusted so that the focus moves inside the area to be treated thereby obtaining a
geometric shape of heating.
A fixed focus spot is determined through the appropriate algorithm. Then,
for example, the relative phase of the applicators to obtain this fixed focus spot is
adjusted 30° one way (positive) and then 30° the other way (negative) to "scan" a
30 larger heated/treated area. Depending on the size of the area to be treated the scan
may focus between. 1800 and 900 or 600 or 1200.
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WO 2004/026098 PCT/US2003/028898

Further objectives and advantages will become apparent from a consideration
of the description and drawings.
Brief Description of the Drawings
The invention is better understood by reading the following detailed
5 description with reference to the accompanying figures, in which like reference
numerals refer to like elements throughout, and in which:
Fig. 1 shows the microwave thcrmotherapy system according to the
invention for heating the prostate under compression from coherent transurethral
and transrectal applicators;
10 Fig. 2 shows the microwave thermotherapy system according to the
invention for heating the prostate under compression from a single non-coherent
transurethral applicator;
Figure 3 shows another embodiment of the microwave therapy system, of
Figure 1 employing an additional interstitial applicator; and
15 Figure 4 illustrates a prostrate surrounded by two or more applicators
outside the skin surface of the patient's body according to yet another embodiment
of the invention.
Detailed Description of the Preferred Embodiment
Description of the Prostate Gland and its Microwave Properties
20 The prostate gland 220 is part of the male reproductive system and is a
solid, walnut-shaped organ that surrounds the first part of the urethra 205
immediately under the bladder 202 and in front of the rectum 210. Prostate cancer
arises from the glands of the prostate and the most common form of prostate
cancer is known as adenocarcinoma, which means a cancer of the glands. Most
25 prostate cancers develop within the bottom portion of the prostate (sometimes
referred to as the peripheral zone which involves roughly 70% of the glandular
prostate) closest to the rectum, and this is the region that needs a significant
amount of treatment. While a digital rectal exam is useful in detecting hardened
areas or lumps in the prostate gland, however it is not very useful for detecting
30 microscopic prostate disease. The use of a transrectal applicator (in addition to a
transurethral applicator) to reach this portion of the prostate is essential for a
complete treatment of the prostate. The central zone of the prostate (closest to the
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WO 2004/026098 PCT/US2003/028898

bladder) is relatively immune to both BPH and prostate cancer diseases. BPH
arises mainly in the transition zone located between the central zone and
peripheral zone.
As discussed above, current medical procedure does not biopsy a tumor
5 until a PSA of 4.0 ng/ml is reached. The data shown in Table 1 indicate that there
is only about a 15% probability of detecting cancer by needle biopsy when the
PSA is less than 4 ng/ml- Although the probability of detecting the cancer is very
low, the actual probability that there are microscopic cancer cells in the prostate is
significant (25% or more) (F.H. Schröder et al, The Journal of Urology, Vol. 163,
10 No. 3, p. 806 (abstract), March 2000) (Eschenbach et al., CA' Cancer J. Clinicians,
Vol, 47, pp. 261-264, 1997). Thus, thormotherapy treatment of the prostate
PSA Level Probability of Detecting Prostate CancelInitial Biopsy
2 ng/ml 1%
2-4 ng/ml 15%
4-10 ng/ml 25%
> 10 ng/ml >50%
Table 1, Probability of detecting cancer cm initial biopsy for different levels of
PSA.
15 is likely warranted, even if the PSA level is in the range of 0 to 4 ng/ml.
Thermotherapy treatment of the prostate for PSA levels below 4 ng/ml is intended
to kill the microscopic cancer cells in the prostate and keep the PSA from rising
above 4 ng/ml
Microwave radiation in the Industrial, Scientific, Medical (ISM) band 902
20 to 928 MHz is commonly used in commercial clinical hyperthermia systems, and
is the primary frequency band considered here. It is known that the proitate is
high-water content tissue and, hence, is similar to muscle tissue which is well
characterized. For normal prostate tissue at 915 MHz, the average dielectric
constant is 50 and the average conductivity is 1.3 S/m. The calculated loss due to
25 attenuation of a 915 MHz plane wave propagating through prostate tissue is
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WO 2004/026098 PCT/US2003/028898

approximately 3 dB per cm. Prostate intraepithelial neoplasia, also known as
atypical hyperplasia and intraductal dysplasia are pre-cancers and are associated
with the development of adenocarcinoma of the prostate. The necplastic cells are
assumed to be higher-water content than the surrounding normal prostate cells and
5 will be heated faster than the normal healthy prostate cells. The normal ductal
tissue in the prostate is assumed to be in the low- to medium-water content range.
The safety of employing radiofrequency (microwave) electromagnetic
fields in order to treat cancer has been questioned. A comprehensive study
recently concluded that there is no association between the incidence or promotion
10 of cancer and exposure to radiofrequeney electromagretic fields in the frequency
range of 3 KHz to 300 GHz (LN. Heynick, Radiofrequency Electromagnetic
Fields (RFEMF) and Cancer: A Comprehensive Review of the Literature Pertinent
to Air Force Operations, AFRL-HE-BR-TR-1999-0145, United States Air Force
Research Laboratory, Directed Energy Bioeffects Division, June 1999). Thus,
15 based on this report, the Applicants realized that there is significant evidence that
microwave treatment of the prostate can safely heat an apparently healthy prostate
gland containing microscopic cancer cells such that no new cancer would be
formed as a result of the microwave treatment.
System for Heating Prostate Tissues
20 Figure 1 shows a preferred system for heating carcinomas and benign
tumor cells in prostate tissues., using an adaptive energy, preferably microwave,
phased array hyperthermia system with E-field and temperature feedback, In order
to heat deep tissues reliably at energy frequencies, it is necessary to surround the
body (prostate lobes 220) with two or more energy applicators 110, 111 (within
25 the urethra 205 and rectum 210, respectively) controlled by an adaptive phased
array algorithm. The energy applicators 110, 111 may be coherent microwave
applicators. The blackened circle, indicated as focus 190, represents a central
tumor or healthy tissue of the prostate 220 that is to be treated.
Focus 190 may represent cancerous conditions of the prostate including
30 one of adenocarcinoma, carcinosarcoma, rhabdornyosarcoma, chondrosarcoma,
and osteosarcoma, or pre-cancerous conditions including one of prostatic
intraepimeliat neoplasia, and benign prostate lesions including benign prostatic
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WO 2004/026098 PCT/US2003/028898

hyperplasia. In addition, the system according to the invention, can treat
apparently healthy tissue in order to prevent the occurrence or re-occurrence of
cancerous or benign conditions.
In the preferred embodiment, an E-field feedback probe 175 can be
5 inserted to an appropriate depth in the tissue of prostate 220 that is to be treated.
Insertion of E-field feedback probe 175 may be achieved under the guidance of an
ultrasound transducer. Means for setting the initial energy phase delivered to each
applicator 110,111 includes E-field feedback signals 450 from the E-field. probe
175 and computer 250 with an appropriate algorithm in order to focus the energy
10 radiation at the inserted E-field probe 175- Preferably, the E-field probe 175 is
used with an adaptive phased array fast-acceleration gradient search algorithm, as
disclosed in U.S. Pat. No. 5,810,888 to Fenn, to target the energy radiation at the
tumor site 190,
In addition, the system according to the invention includes means for
15 setting the initial energy or microwave power delivered to each energy applicator,
and means for monitoring the temperatures of walls of the urethra and rectum
adjacent the prostate that is to be treated to ensure that those walls are not
overheated. The means for monitoring urethral and rectal walls may include
temperature feedback sensors 410 that are inserted non-invasively against file
20 urethral and rectal walls (215,216) in order to monitor the temperatures of the
urethral and rectum walls adjacent the prostate tissue. Temperature feedback
sensors 410 send temperature feedback signals 400 to computer 250 where signals
400 are used to adjust the relative microwave power level that is to be delivered to
applicators 110, 111 to heat the tumor or tissue at focus 190.
25 Preferably, the design of the transurethral and transrectal energy
applicators, which preferably are microwave applicators, is according to U.S, Pat.
No, 5,007,437 to Sterzer. The transrectal applicator, in particular, may use a
reflector or a phased array to direct microwave energy preferentially towards the
prostate. The applicators can be noninvasive applicators such as waveguide,
30 monopolc, or dipole antennas, or interstitial applicators 109 (see Figure 3) such as
monopole or dipole antennas. In a. preferred embodiment, the applicators can be
. driven coherently as a phased array, in addition, multiple applicators 108
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WO 2004/026098 PCT/US2003/028898
surrounding the prostate 220 (see Figure 4) that can be driven non-coherently in a
multiple frequency array can be used to selectively heat the prostate tissue.
Preferably, the body or prostate 220 is compressed between two
compression balloons 112,113, which surround transurethral and teansrectal
5 applicators 110,111. respectively. Compression balloons 112,113 can be inflated
with distilled or deionized water. In the alternative, the compression balloons
112,113 can be inflated pneumatically or by other known means to inflate
balloons. Compression balloons 112, 113 are made from a material such as latex
that is transparent to microwaves. In addition, to immobilizing the prostate tissue
10 and fixing the positions of the applicators, prostate compression has a number of
potential advantages for hyperthermia treatments. Utilization of prostate
compression results in less penetration depth required to achieve deep microwave
heating and reduces blood flow, which also improves the ability to heat tissue.
Injection of a local anesthetic drug such as lidocaine with ephmephrine, or
15 anti-angiogenesis drug into the prostate tissue can be used to reduce blood flow as
well. In a preferred method, according to the invention, both the prostate
compression technique and drug therapy for reducing blood flow in the prostate
gland are used to allow rapid heating of the microscopic, malignant and benign
cancer cells. This preferred method can be administered as a preventive means
20 for cancer and BPH when PSA levels are less than 4, and for BPH when the AUA
Symptom Index scores less than 13.
Compressing the prostate from the inside and outside of the prostate moves
the surface of the prostate gland farther from the microwave applicator radiators,
which helps to reduce superficial hot spots. In a preferred embodiment, the
25 applicator would have a fluid filled cavity thai would improve coupling of the
microwave energy from the applicator to tissue to be treated. Cooling of the fluid,
such as distilled or deionized water, within the transurethral and transrectal
applicators or applicator balloons during hyperthermia treatments helps avoid the
potential for developing hot spots in the urethra 205 and rectum 210 thereby
30 protecting the urethral and rectal walls from overheating.
Prior to the adaptive phased array hypcrthermia treatment, the prostate is
compressed between compression balloons 112,113 and a single invasive E-field
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feedback probe 175 is inserted within the central tissue site (focus 190) in the
prostate, parallel to the polarization of the microwave applicators 110, 111. The
microwave applicators 110, 111 are either monopole or dipole antenna radiators of
straight or helical shape. E-field probe 175 is used to monitor the focal E-field
5 amplitude as the phase snifters are adjusted for maximum feedback signal using an
adaptive phased array gradient search algorithm. Noninvasive temperature sensors
410 monitor the urethral and rectal wall temperatures at positions 184,185,
respectively, and these signals are individually transmitted to the computer as
temperature feedback signals 400.
10 The tips of temperature sensors 410 can be attached to the outside of the
transurethral and transrectal compression balloons 112,113 as long as the tips are
thermally insulated. The thermal isolation can be achieved by mounting a thin pad
(not shown) between the temperature probe and the outside surface of the balloon,
from the effects of the cooling fluid contained with the compression balloons. The
15 dual-applicator adaptive phased array of the invention together with the E-field
feedback probe allows the phase shifters to be adjusted so that a concentrated
E-field can be generated permitting focused hearing in tissue at the appropriate
depth.
Preferably, temperature sensors 410 are non-invasively inserted through
20 file openings of the uretnra 205 and rectum 210 so that the sensors 410 are in
pressure contact with the respective, urethral and rectal wall. Thus, as shown in
Figure 1, two temperature feedback probe sensors 410 are located in the urethra
205 and rectum 210, respectively and produce temperature feedback signals 400.
Two microwave water-cooled catheters 300,301 with microwave applicators 110,
25 111, respectively, are positioned in the urethra 205 and rectum 210, Transurethral
catheter 300 contains a Foley balloon 118 that is air inflated in the bladder 202 to
fix the microwave applicator 110 in the correct position with respect to the target
area of the prostate.
For coherent treatments, an oscillator 105 is divided at node 107 and feeds
30 phase shifters 120, Oscillator 105 in a preferred method is a microwave energy
source at approximately 915 MHz. The phase control signal 125 controls the phase
of the microwave signal over the range of 0 to 360 electrical degrees. The
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WO 2004/026098 PCT/US2003/028898

microwave signal from each phase shifter 120 feeds into microwave power
amplifiers 130. The resultant microwave signal is controlled by a computer-
generated control signal 135, which sets the initial microwave power level
delivered to each microwave applicator. Microwave signals 150 in the form of
5 coherent 915 MHz microwave power is delivered by the microwave power
amplifier 130 to the two applicators 110, 111 while phase shifters 120 in each
channel are adjusted to maximize and focus the microwave energy at the E-field
probe sensor 175 so that microwave power is maximized at the focus position 190.
The treatment then begins.
10 In another embodiment, the means for monitoring temperature of the
prostate is a temperature probe that is inserted at an appropriate depth in the
prostate tissue. In this case, after the means for setting the initial relative energy
phase delivered to each applicator is focussed at the E-field probe 175, the E-field
probe can be removed and the temperature probe 176 can be inserted in its place
15 temperature at an appropriate depth in the prostate tissue.
In yet another embodiment envisioned by the invention, a second
temperature monitoring means, in addition to the non-invasive temperature
sensors in pressure contact with the watts of the urethra and the rectum, is
provided. The second temperature monitoring means is the invasive temperature
20 probe 176 that is inserted in the prostate tissue in the same spot from which the E-
field probe 175 removed.
The system and method according to the invention enable all of the treated
prostate carcinomas, pre-cancerous cells, and benign lesions to be destroyed when
the desired total microwave energy dose has been delivered to the microwave
25 applicators while avoiding damage to the normal tissue of the prostate.
For non-coherent treatments, separate oscillators 105, which preferably
operate at 915 MHz, could feed two microwave power amplifiers 130 that are
computer controlled and deliver microwave power to two applicators 110, 111.
For applications where a single applicator can be used, as shown in Figure 2, a
30 single applicator 110 located in the urethra is preferred.
During the hyperthermia treatment, the microwave signals 150 and power
level delivered to each of the applicators is measured as a power feedback signal
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WO 2004/026098 PCT/US2003/028898

500, which is sent to a microprocessor or computer 250 such as a PC The power
control signal of the power amplifiers 130 is adjusted either manually or
automatically to control the urethra and. rectum temperatures, as well as, the
equivalent thermal dose delivered to the prostate tissue. The sensors 410 measure
5 the urethral and rectal wall temperatures and the power control signal 135 is
adjusted based on the sensed temperature to avoid high temperatures that could
cause bums or blisters. The amount of compression realized by compression
balloons 112,113 is adjusted as necessary during treatment to provide patient
comfort. Each time the prostate compression is adjusted, for coherent treatments,
10 the phase shifters 120 are Teadjusted/refocused so that the E-field probe 175
receives maximum power.
According to the system according to the invention, means for monitoring
the microwave energy delivered to the microwave applicators 110,111 monitor the
delivered energy/power during treatment and when the desired total microwave
15 energy has been delivered by the microwave applicators 110,111 to the prostate,
means for terminating the treatment turn off the energy radiation to the
applicators. That is, the system and method according to the invention
automatically turns off the energy that is being delivered to the prostate, thereby
completing the hyperthermia treatment when a desired total microwave energy
20 dose has been delivered to the prostate 220. In a preferred embodiment, the total
microwave energy dose produces a total equivalent thermal dose in prostate
tumors, which is approximately between 60 minutes and 400 minutes relative to
43 degrees Celsius. The total microwave energy, since the start of the treatment,
delivered to the microwave applicators is computed within computer 250 and can
25 be displayed on the computer monitor 260 during the treatment.
As an alternate embodiment, means are provided for monitoring the
microwave power level delivered to the E-field probe 175 to determine-when the
treatment should be terminated. According to this embodiment, the total
microwave energy calculated from the E-field feedback signal 450 received by the
30 E-field probe 175 is used to control the length of the treatment. This E-field
feedback signal 450 can be useful for both coherent and non-coherent treatments,
In order to determine the effectiveness of the treatment, me prostate tissue is
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imaged with one of x-ray and magnetic resonance imaging before and after the
microwave total energy dose is administered, as well as pathological results from
needle biopsy of the prostate tissues.
For coherent treatments, file single invasive E-field. probe 175 can be
5 replaced, with two noninvasive E-field sensors at fixed positions 186,187 within
the urethra and rectum, respectively. The E-field sensors are inserted in the
natural openings of the uretnra 205, and rectum 210 and fixed in a position that is
suitable to heat the tumor or healthy tissue. E-field sensors can be attached to the
urethral and rectal walls at positions 186,187, but they do not have to be in
10 contact with the urethral and rectal walls. Ultrasound, x-rays or other known E-
field monitoring device can verify the suitable E-field sensor positions. The total
power measured by the two noninvasive E-field sensors is minimized (as in U.S,
Pat- No. 5,810,888) by adjusting the microwave phase shifters 120, to create a
focused E-field in the central portion of the prostate, or the area of the prostate to
15 be treated.
With this embodiment, there is no risk of infection due to an inserted
probe, no risk of scarring of the skin by a procedure which requires nicking the
skin and inserting a probe, and no risk of spreading cancer cells as an inserted E-
field probe is not used. The E-field sensors merely are fixed within the urethra
20 and rectum and thus, do not pass through a tumor bed thereby reducing the
possibility of inadvertently seeding viable cancer cells during a surgical procedure,
thus reducing local recurrences of the cancer in surrounding tissues. Likewise,
since both the temperature and E-field sensors can be placed in the urethra 205
and rectum 210 according to this method, the instant invention would work well
25 when there is no defined single area in the prostate such as in the treatment of
microscopic prostate disease.
Preferably, each channel (on either side of node 107) of the phased array
contains an electronically-variable microwave power amplifier 130 (0 to 100 W),
an electronically-variable phase shifter 120 (0 to 360 degrees), and water-cooled
30 micro wave applicators 110,111.
While the preferred embodiment discloses microwave energy at
approximately 915 MHz, the frequency of the microwave energy may be between
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100 MHz and 10 GHz, The frequency of the microwave energy could be selected
from the range of 902 MHz and 928 MHz. In fact, lower frequencies of energy
may be used to ablate or prevent cancerous tissue.
In a preferred embodiment, the initial microwave power delivered to each
5 applicator is between 0 and 70 Watts, preferably between 20 and 60 Watts. Over
the entire treatment of the tissue, the microwave power delivered to each
applicator may be adjusted over the range of 0-150 Watts to deliver the desired
microwave energy dose and to avoid overheating the urethra and rectum, In
addition, the relative microwave power delivered to the two microwave
10 applicators is adjusted between -180 degrees and 180 degrees before and during
the treatment to create a focussed field in the prostate tissue. Typically, more
microwave power is required for non-coherent applicator treatments than for
coherent applicator treatments.
IN a preferred embodiment, a 0.9-mm outaide-diameter (OD) invasive
15 E-field coaxial monopole probe (semi-rigid RG-034), with the center conductor
extended. 1 cm, can be used as E-field probe 175 to measure the amplitude of the
electric field directed to the tissue and to provide the feedback signal 450 used to
determine the necessary relative phase for the electronic phase shifters prior to
treatment, Coaxially-fed monopole probes of this type have been used to make
20 accurate measurements of linearly polarized electric fields in compressed breast
phantoms (Fenn et al.f International Symposium on Electromagnetic Compatibility
17-19 May 1994 pp. 566-569). This linearly-polarized E-field probe is inserted
within a 1.6 mm OD teflon catheter. Thermocouple probes (Physitemp
Instruments, Inc., Type T copper-constantan, enclosed within a 0.6 mm OD teflon
25 sheath) can be used to measure the local temperature in the tumor during
treatment. These temperature probes have a response time of 100 ms with an
accuracy of 0.1° C. Fiber-optic temperature probes may also be used.
The E-field probe 175 is used with the adaptive phased array fast-
acceleration gradient search algorithm, as disclosed in U.S. Pat No. 5,810,888 to
30 Fenn, to target the microwave radiation at the tumor site. The temperature sensed
by the invasive temperature probe 175 in the tumor could be used as a real-time
feedback signal during the treatment. This feedback signal 450 could be used to
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control the microwave output power level of the variable power amplifiers, which
set and maintain the focal temperature at the tumor site in foe range of 43 to 46° C.
The power and phase delivered to the two channels of the phased array are
adjusted adaptively using digital-to-analog converters under computer control.
5 Total Microwave Energy Dose can be used to estimate the required heating
time. That is, Applicants realized that a non-invasive equivalent temperature
sensing means could replace the invasive temperature probes, and that the Total
Microwave Energy Dose reliably could be used to control the duration of
treatment. The prostate compression, as mentioned earlier, reduces blood flow,
10 which likely eliminates the effects of blood flow on the required microwave
energy for treatment, and may reduce the variation in microwave energy that can
be expected in microwave treatments.
Accordingly to a preferred embodiment, the total microwave energy
delivered to the waveguide applicators to determine completion of the treatment is
15 between 25 kilo Joules and 250 kilo Joules. The total amount of microwave
energy dose that would destroy any cancerous or precancerous tissue would be
approximately 175 kilo Joules, But, under certain conditions, the required
microwave energy dose may be as low as 25 kilo Joules.
As applicants recognized, compression of a body that results in a smaller
20 thickness may require less microwave energy dose (compared to a compression
that results in a larger thickness) for effective treatments in preventing or
destroying cancerous, pre-cancerous or benign lesions. It is important to select an
appropriate initial microwave power level (P1,P2) delivered to each applicator as
well as the proper microwave phase between the two applicators to focus the
25 energy at the area to be treated.
During hyperthermia treatment, it is necessary to monitor the urethral and
rectal wall temperatures so that they do not rise significantly above about 41
degrees Celsius for more than several minutes. The equivalent thermal dose for
the urethral and rectal wall sensors can be calculated (Sapareto, et al, Internationa]
30 Journal of Radiation Oncology Biology Physics, Vol. 10, pp. 787-800,1984) and
can be used as a feedback signal Typically, it is necessary to avoid delivering
more than a few equivalent minutes thermal dose. Avoiding high urethral and
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rectal temperatures according to the invention is accomplished by adjusting the
individual powers (P1, P2) delivered to the applicators during treatment either by
manual or automatic computer control
Doppler ultrasound can be used to measure blood flow in tumors and
5 surrounding prostate tissue, before and during treatment to plan and adjust the
microwave energy dose. For example, less energy dose is required when the
tumor blood flow rate is reduced which can occur when the prostate is compressed
and/or the tumor is heated to therapeutic temperatures. Alternatively, the water
content and. dielectric parameters of prostate tumor tissue from needle biopsies
10 could be measured and used to determine, prior to the treatment, me required
microwave energy dose. For example, higher water content and higher electrical
conductivity in the tumor would reduce the amount of required microwave energy
dose. In addition to the above variables, the size of the tumor impacts the required
microwave energy dose. Larger tumors are more difficult to heat than smaller
15 tumors and require a larger microwave energy dose. An initial treatment planning
session involving a low-dose delivery of microwave energy to assess the
heatability of the tumor, followed by a complete treatment at the full required
microwave energy dose may be performed.
Clinical Motivation for Safety Features
20 In thermotherapy treatment of prostate cancer and benign prostatic
hyperplasia, it is desirable to achieve therapeutic temperatures in the prostate
while maintaining lower temperatures in the urethra and rectum. As the
surrounding tissues in the urethra and rectum tend to be heated while microwave
energy irradiates the prostate gland, methods for safely heating the prostate while
25 protecting the surrounding healthy tissues need to be devebped.
In Figures 1-4, following application of microwave thermotherapy,
microwave power control signals 135 command at least one of the microwave
power amplifier 130 for the transurethral applicator and/or the microwave
amplifier 130 for the transrectal applicator to turn off and at least one of a
30 transurethral balloon 112 and a transrectal balloon 113 maintain pressure on the
prostate gland to reduce blood flow thereby trapping heat to accumulate additional
thermal dose. This safety embodiment can be used for heat-alone prostate
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treatments or when thermotherapy is used with chemotherapy or to release
chemotherapy from thermosensitive liposomes as described in U.S. Pat. No.
5,81 0,888 to Fenn. The blood flow rate can be measured and displayed during
prostate compression by doppler ultrasound imaging in order to verity and adjust
5 the blood flow rate in the prostate by varying the amount of prostate compression.
In chemotherapy, thermosensitive liposome delivered chemotherapy, or
gene therapy for prostate cancer it is desirable to deliver as much drug as possible
to the tissue to be treated of a patient. The desired therapeutic agent in the form of
chemotherapy, thermosensitive liposome delivered chemotherapy, gene therapy, or
10 other agent is infused into the blood stream of a patient. The compression of the
transurethral and/or transrectal balloon catheters may be modulated so that the
blood flow in the prostate tissue can be adjusted. The blood flow in the prostate is
reduced by increasing pressure of the compression balloons in the urethra and/or
rectum. This reduction in blood flow in the prostate means that me infused
15 therapeutic agent will spend more time within the prostate tissue, potentially
increasing the therapeutic value. Further, if the therapeutic agent spends more
time within the prostatic blood vessels, there is an increased likelihood that the
therapeutic agent will extravasate (permeate or leak) from the blood vessels into
the prostatic tissues to reach the prostate cancer cells. Consequently, the
20 compression of the prostate may increase the amount of therapeutic agent
delivered to the prostate while decreasing the amount of therapeutic agent released
into normal healthy surrounding tissues.
The desired sequence of balloon compression of the prostate is as follows.
After chemotherapy, thermosensitive liposome delivered chemotherapy, gene
25 therapy, or another agent is infused into the patient's bloodstream, the prostate
gland is compressed by at least one of the transurethral and transrectal balloon
catheters for a period of between 1 minute and 10 minutes. Then, at least one of
the transurethral and transrectal balloons is deflated to allow normal blood flow
into the prostate for a period of less than 1 minute to allow the therapeutic agent to
30 enter the prostatic bloodstream, but without substantially lowering the temperature
of the prostate. And then the prostate gland is compressed again for a period of
between 1 minute and 10 minutes to reduce the blood flow thereby trapping the
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therapeutic agent within the prostate gland. The above described process of
inflation and deflation of the balloon catheter(s) is repeated until the desired
amount of therapeutic agent is delivered to the prostate while the prostate is
heated.
5 In a preferred embodiment, the chemotherapy agent is Doxorubicin
(Adriamycin). In another preferred embodiment, the thermosensitive liposome
formulation is as described in U.S. Pat No, 6,200,598 to Needham.
Applicants envision that doppler ultrasound imaging may be employed to
determine the blood flow rate of the tumor. That is, doppler ultrasound imaging
10 can measure the tumor blood flow rate with or without compression of the prostate
and use these measurements as feedback during the treatment in order to assess
any damage to the prostate tumor vasculature.
Simplified Microwave_Radiation Theory
Microwave energy from hyperthernia applicators, in the near field of a
15 body, radiates as a spherical wave with the electric-field amplitude varying, in
part, as the inverse of the radial distance r from the applicator. Additionally, the
amplitude decays as an exponential function of the product of the attenuation
constant α of the body tissue and the distance d traversed (or depth) within the
body as indicated, in Figure 1, The electric-field phase varies linearly with
20 distance according to the product of the phase propagation constant β and distance
d. For simplicity, dual-opposing applicators are analyzed here under the
assumption that the applicator radiation is approximated by a plane wave.
Mathematically, the plane-wave electric field versus depth in tissue is given by
E(d)=Eo exp(-αd) exp(-iβd), where Eo is the surface electric field (in general
25 represented by an amplitude and phase angle), and i is the imaginary number
(Field and Hand, An Introduction to the Practical Aspects of Clinical
Hyperthermia, Taylor & Francis, New York p. 263,1990),
Plane-wave electromagnetic energy, at the microwave frequency of 915
MHz, attenuates at a rale of about 3 dB per cm in high-water content tissue, such
30 as prostate tissue. Thus, a single radiating applicator has a significant fraction of
its microwave energy absorbed by intervening superficial body tissue compared to
the energy that irradiates deep tissue, likely creating a hot spot in superficial tissue.
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Since surface cooling with, either air or water protects tissue only to a maximum
depth of about 0.25 to 0,5 cm, in order to avoid hot spots, it is necessary to
introduce a second phase-coherent'applicator, having the same microwave
radiation amplitude as the first applicator. The second phase-coherent applicator
5 can theoretically increase the power (and hence the energy) delivered to deep
tissue by a factor of four compared to a single applicator (Field and Hand, p. 290,
1990).
The pbase characteristics of the electromagnetic radiation from two or
more applicators (known as a phased array) can have a pronounced affect on the
10 distribution of power delivered to different tissues. The relative specific
absorption rate (SAR) in homogeneous tissue is approximated by the square of the
electric-field amplitude |E|2. The SAR is proportional to the rise in temperature
over a given time interval. A simplified case, homogeneous prostate tissue, in
which the microwave radiation is focused at a central tissue site, is described in
15 detail below. As described in an. article by Fenn et al., international Symposium
on Electromagnetic Compatibility, Sendai, Japan, Vol. l0,No. 2, May 17-19,
1994, pp. 566-569, the effects of multiple microwave signal reflections within the
phantom can be ignored.
The wavelength in homogeneous normal prostate tissue (with approximate
20 dielectric constant 50 and electrical conductivity 13 S/m) is approximately 4,5 cm
at 915 MHz, and the microwave loss is 3 dB/cm. The attenuation constant α is
0.34 radians/cm and the propagation constant β is 1.4 radians/cm (or 80
degrees/cm). (For a compressed prostate thickness of 2.25 cm, the electric field of
a single applicator radiating on the left side is E0 at the surface of the prostate,
25 -i0.7E0 (where i represents a 90-degree phase shift) at the central position (1.125
cm deep), and -0.5E0 at the right surface. Combining two phase coherent
applicators yields an electric-field value of 0.5EO on both surfaces and -i1. 4EO at
the central position (1.125 cm depth). Thus, for the compressed prostate, by
squaring the above coherent E-fields to compute SAR, there is a significantly
30 lower SAR at the surface, by about a factor of 2.0 compared to the central SAR,
The 180-degree phase shift experienced by the microwave field transmitted
through 2.25 cm of prostate tissue, partly cancels or nulls the field entering the
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tissue with 0-degree phase shift. Due to destructive interference of the
microwaves away fiom the central focus lower temperatures in the superficial
prostate tissues would be expected. Measurement and enforcement of lower SAR
on the opposing surfaces effectively focuses the microwave energy deep in the
5 prostate. In cases where it is desirable to radiate the superficial or peripheral zone
prostate tissues more strongly, the compression thickness can be larger than 2.25
cm so that the propagating wave phase delay is longer and the two waves do not
cancel at the surface, or only one of the ixansurethral or transrectal applicators
(especially the transrectal applicator) can be used to heat the prostate.
10 Repeating the above calculation, but now for non-coherent applicators, for
a compressed prostate thickness of 2.25 cm, the electric field of a single applicator
radiating on the left side is Eo at the surface of the prostate, -i0.7E0 (where i
represents a 90-degree phase shift) at the central position (1.125 cm deep), and
-0.5E0 at the right surface. Combining two applicators non-coherentiy, by
15 squaring the individual E-fields and adding them, yields a SAR. value of 1.5E02 on
both surfaces and 0.98 E02 at the central position (1.125 cm depth). Thus, for the
compressed prostate, by squaring the above non-coherent E-fields to compute
SAR, there is a significantly higher SAB, at thd surface, by about a factor of 1.5
compared to the central SAR, For this reason, it is more difficult to heat deep
20 prostate tissue with the non-coherent array compared to the coherent array.
However, as mentioned earlier, for prostate cancer treatment some of the prostate
cancer cells can be located close to the rectum and non-coherent treatment may
provide adequate heating.
The adaptive phased array system according to the invention uses two
25 microwave channels, fed by a common oscillator 105, containing two
electronically adjustable phase shifters 120 to focus the microwave energy at an
E-field feedback probe 175. This inventive adaptive phased array system has
significant advantage over a non-adaptive phased array. A non-adaptive phased
array with two channels could., in theory, produce a null, a maximum, or an
30 intermediate value of E- field depending on whether the two waves are 180 degrees
out-of-phase, completely in-phase, or partly out-of-phase, respectively. That is,
the microwave phase delivered to the microwave applicators, according to the
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invention, can be adjusted between -180 degrees and 180 degrees before and
during the treatment to create a focused field in the prostate tissue.
The adaptive phased array according to the invention automatically focuses
the E-field in the presence of all scattering structures in the tissue. Thus, the
5 adaptive phased array according to the invention should provide more reliable
deep focused heating compared to manually adjusted or pre-treatment planning
controlled phased, arrays as described in U.S. Patent No. 4,589,423 to Turner.
Furthermore, the adaptive phased array system according to the invention does not
use an invasive temperature probe, which could scatter or alter the E-field at the
10 tumor site.
Calculation of Microwave Energy
Electrical energy consumption is commonly expressed in units of kilowatt
hours. Mathematically, the expression for the microwave energy W delivered by
an applicator is given by (Vitrogan, Elements of Electric and Magnetic Circuits,
15 Rinehart Press, San Francisco, pp. 31-34, 1971):
W=ΔtΣPt. (1)
In the above equation. Δt represents the constant intervals (in seconds) in which
microwave power is measured and the summation Σ is over the complete
treatment interval with the power (in Watts) in the ith interval denoted by Pi
20 The microwave energy Whas units of watt-seconds, which is also
designated as Joules. For example, in three consecutive 60-second intervals if the
microwave power is 30 watts, 50 watts, 60 watts, respectively, the total
microwave energy delivered in 180 seconds is calculated as W= 60 (30 + 50 + 60)
= 8,400 watt-seconds = 8,400 Joules = 8.4 kJ.
25 To understand better the focused energy per unit time W' (where' denotes
prime) deposited at a central position in homogeneous prostate tissue of varying
thickness (denoted by D) by dual-opposing applicators, consider the following
calculation for coherent treatments. Let P1 and P2 be the power delivered to the
two applicators, respectively. The electric field radiated by each applicator is
30 proportional to the square root of the power delivered, to the applicator- Assuming
symmetry, the radiated fields are in-phase at the central focused position from the
two applicators. Assuming equal power from each applicator, that is, P1 - P2 = P,
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and plane wave illumination, then the focused energy per unit time at the central
depth is expressed as
W'(D)= |E|2=4Pexp(-αD). (2)
Calculation of Equivalent Thermal Dose
5 the cumulative or total equivalent thermal dose relative to 43 degrees
Celsius is calculated as a summation (Sapareto, et al, International Journal of
Radiation Oncology Biology Physics, Vol, 10, pp, 787-800,1984):
t43ºC equivalent minutes -Δt ΣR(47-T) , (3)
where Σ is the summation over a series of temperature measurements during the
10 treatment, Tis the series of temperature measurements (T1, T2 T3,...), Δt is the
constant interval of time (unite of seconds and: converted to minutes) between
measurements, R is equal to 0.5 if T>43º C and R is equal to 0.25 if T equivalent thermal dose calculation is useful for assessing any possible heat
damage to the prostate tissues, urethra and rectum.
15 Equivalents
While this invention has been particularly shown, and described with
reference to preferred embodiments thereof, it mil be understood by those skilled
in the art that various changes in form and details maybe made therein without
departing from the spirit and scope of the invention as defined by the appended
20 claims. For instance, although the hyperthermia system described herein is with
respect to the treatment of prostate carcinomas and benign prostate lesions, the
invention is applicable to the treatment of other types of cancers such as breast,
liver, lung, and ovarian. In addition to the disclosed preferred embodiments, it is
understood that the methods disclosed here can be applied, to microwave,
25 radiofrequency, or ultrasound thermotherapy treatments of other appendages and
portions of the human body, such as legs and arms and the torso that can be
compressed with a balloon cuff (for example, a blood pressure cuff) or other
device. It is also understood that larger or smaller numbers of array antenna
applicators, or single antenna, applicators such as an implant, or transurethral or
30 transrectal applicator, may be used with similar results- Some of the methods and
techniques described herein are also applicable to ultrasound hyperthermia system
particularly the use of energy dose for feedback control. The system according to
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the invention can be used to enhance radiation therapy or for targeted drug
delivery and/or targeted gene delivery using thermosensitive liposomes or for
targeted gene therapy. The invention is also applicable to non-medical
hyperthermia systems, such as those used for industrial heating.
5
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PCT/US2003/028898
WE CLAIM:
1. A method for treating tissue of the prostate comprising the step of
compressing the prostate following the application of one of microwave energy,
ultrasound energy, laser energy and energy via a fluid to reduce prostatic blood
flow in order to accumulate added thermal dose in the treated prostate tissue.
2. The method for treating the prostate according to Claim 1, wherein the
application of one of microwave energy, ultrasound energy, laser energy and
energy via a fluid is achieved with a single applicator, said applicator being one of
an implant, a transurethral applicator and a iransrectal applicator.
3. The method for treating the prostate according to Claim 1, wherein the
compression step is achieved by inflating at least one of a transurethral catheter
balloon and a transrectal balloon,
4. The method for treating the prostate according to Claim 3, further
comprising the step of using real-time feedback from a doppler ultrasound velocity
imaging system to adjust and verify the amount of prostate compression as a result
of the transurethral and/or transrectal balloon inflation,
5. A method for safely administering thermotherapy, comprising the steps
of compressing at least one of an organ and an appendage to be treated by using
one of a balloon catheter and a balloon cuff to reduce organ or appendage blood
flow therein; and
applying one of chemotherapy, gene therapy, thermosensitive liposomes
containing chemotherapy, and radiation therapy in combination with the
compression in order to treat cancer and/or a benign condition of the organ and/or
appendage.
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6. The method for safely administering thennotherapy according to Claim
5 ,wherein the balloon catheter is at least one of a transurethral balloon catheter
and a transrectat balloon catheter,
7. The method for safely administering thcrmomerapy according to Claim
6, wherein the organ being treated is the prostate and a balloon catheter is
employed to compress the catheter, and further comprising the steps of adjusting
the amount of prostate compression and verifying the amount of prostate
compression as a result of the transurethral and/or transrectal balloon catheter.
8. The method for safely administering thennotherapy according to Claim
7, wherein the steps of adjusting and verifying are achieved using real-time
feedback from a doppler ultrasound velocity imaging system.
9. The method for safely administering thennotherapy according to Claim
5, wherein the organ is the prostate, a balloon catheter is used to compress the
prostate and the compressing step of the prostate occurs after one of
chemotherapy, thermosensitive liposomes containing chemotherapy, and radiation
therapy is infused into the bloodstream of a patient to deliver a therapeutic agent;
said compressing step including inflating the balloon catheter thereby compressing
the prostate gland for a first time period between approximately 1 minute to
approximately 10 minutes, and then, after the compression of the first time period,
deflating the balloon catheter to allow unrestricted blood flow into the prostate for
a second time period of less than approximately 1 minute.
10. The method for safely administering thermotherapy according to
Claim 9, wherein
the process of inflating and deflating the balloon catheter is repeated until the
desired amount of therapeutic agent is delivered to the prostate.
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11. The method for safely administering thermotherapy according to
Claim 5, wherein an appendage is to be compressed and treated for cancer and/or a
benign condition.
12. The method for safely administering thermotherapy according to
Claim 11, wherein the appendage is one of a arm, leg or torso.
13. A method for effectively delivering chemotherapy, thermosensitive
liposomes containing chemotherapy, and gene therapy comprising the steps of
applying one of chemotherapy, thermosensitive liposomes containing
chemotherapy, and gene therapy to an organ or an appendage; and then
modulating inflation and deflation of one of a balloon catheter, and a balloon cuff
about the organ or appendage to compress the organ or appendage to vary the
blood flow therein.
14. The method for effectively delivering chemotherapy, thermosensitive
liposomes containing chemotherapy, and gene therapy according to Chum 13,
further comprising the step of heating tissue of the organ or tissue with one of
microwave, ultrasound, radiofrequency, and laser energy and wherein the
modulating compression of the organ or appendage and thermotherapy together
increase the medicinal effects of one of the delivered chemotherapy,
thermosensitive liposomes containing chemotherapy, and gene therapy.
15. The method for effectively delivering chemotherapy, thermosensitive
liposomes containing chemotherapy, and gene therapy according to Claim 14,
wherein the organ being treated is the prostate,
16. The method for effectively delivering chemotherapy, thermosensitive
liposomes containing chemotherapy, and gene therapy according to Claim 14,
wherein the appendage being treated is one of an arm, a leg and a torso.
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17. A method for effectively delivering liposomes containing
chemotherapy to a prostate to be treated comprising the step of time-modulating
balloon catheter compression of the prostate gland to reduce blood flow in the
prostate thereby reducing blood flow and providing more time for liposomes
containing chemotherapy to deliver chemotherapy to the prostate.
18. The method for effectively delivering liposomes according to Claim
16, wherein the step of time-modulating the balloon catheter compression uses
real-time feedback from a doppler ultrasound velocity imaging system to adjust
and verify the amount of prostate compression.
19. The method for effectively delivering liposomes according to Claim
16, wherein the compression step is achieved by inflating at least one of a
transurethral catheter balloon and a transrectal balloon.
20. A method of thermotherapy of a tumor comprising the step of using
doppler ultrasound imaging to measure the blood flow rate in a tumor region, with
or without compression, for feedback during thermotherapy in order to assess any
damage to the tumor.
21. A method for early treatment of cancerous, pre-cancerous, or benign
conditions of a prostate by irradiation of the prostate, comprising the steps of:
a) Determining one of the prostate specific antigen (PSA) level and the
American Unological Association (AUA) Symptom Index of a patient;
b) compressing the prostate of the patient; and
c) Heating the patient's compressed prostate with focused microwave
energy when one of the PSA level is less than 4.0 ng/ml and the AUA index is less
than 13.

Documents:


Patent Number 213798
Indian Patent Application Number 00551/KOLNP/2005
PG Journal Number 03/2008
Publication Date 18-Jan-2008
Grant Date 16-Jan-2008
Date of Filing 01-Apr-2005
Name of Patentee CELSION CORPORATION
Applicant Address 10220 OLD COLUMBIA ROAD, SUITE I, COLUMBIA, MD 21046-1785, U.S.A.
Inventors:
# Inventor's Name Inventor's Address
1 FENN ALAN J 4 SHERMAN BRIDGE ROAD, WAYLAND, MA 01778, U.S.A.
2 MON JOHN 16903 HARBOUR TOWN DRIVE, SILVER SPRING, MD 20905, U.S.A
PCT International Classification Number A61F 2/00
PCT International Application Number PCT/US2003/028898
PCT International Filing date 2003-09-16
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 10/247,747 2002-09-20 U.S.A.