URORADIOLOGY
TRANSRECTAL U L T R A S O U N D - G U I D E D INTERSTITIAL RADIATION THERAPY FOR LOCALIZED PROSTATE CANCER STANLEY A. BROSMAN, M.D. KENNETH TOKITA, M.D.
From the Departments of Surgery/Urology and Radiation Oneology, St. John's Hospital and Health Center, Santa Monica, California ABSTRACT--The use of interstitial implants for the treatment of low-stage prostate cancer using transrectal ultrasound guidance is evaluated in 80 -patients. This outpatient procedure involves the placement of needles through a template and into the prostate. Ultrasound guidance is used to place the needles into a preselected location. The needles are loaded with a radioactive source. In this study Palladium-103 was utilized. This technique allows accurate and complete seeding of the prostate. There was a 50 percent or greater decrease in prostate size in all of the patients who were implanted. Prostate-specific antigen (PSA) levels became normal or decreased by more than 50 percent in 97 percent of the patients. Most patients experienced urethral irritative symptoms which lasted up to five months, but none of the patients experienced rectal symptoms lasting longer than a month. The mean follow-up is 11.8 months which is too brief to ascertain the effectiveness of this therapy. The method appears to be safe and may represent an alternative to external beam irradiation.
Radiation therapy is an important option in the management of patients with prostatic cancer. This form of therapy is particularly effective when the cancer is of low volume and confined to the prostate. To enhance the effectiveness of radiotherapy, investigators at the University of Iowa began implanting radioactive gold seeds into the prostate in 1952.1 This technique did not gain wide popularity, but physicians at Memorial Sloan-Kettering Cancer Center in New York reevaluated the use of this type of radioactive seed implant therapy for prostate cancer in 1970. They implanted iodine-125 seeds into the prostate using a suprapubic operative approach. 2 Although the prostate was visible, there was a problem in obtaining good distribution of the seeds. This led to a high rate of tumor recurrence and progression, a The procedure was abandoned by most urologists and radiation therapists but the brachytherapists who were initially involved at Memorial Sloan372
Kettering Cancer Cente: and improving this meth Two important lessons early experience. F i r s t , plant radioactive seeds J relative safety; secon diotherapy could destroy ior of prostate cancer ce] solved was how to obtail distribution of the radial the prostate. The develo]; trasonography represent, sary to permit the accu dioactive seeds into the added advantage of not l tervention. In 1983 Holm et al. s their experience with placed perineally throt transrectal ulrasound gui and Schumacher9,1° mo
UROLOGY
/
OCTOBER 1991
/
VC
an treating patients in 1985. Palladiumame available in 1988, and several med~ters have begun to use this isotope to 0state cancer. ~cribe the technical features of radioacd implantation and the complications dd with this therapy in 80 patients who eared with Palladium-103. * Material and Methods
~tion candidates for this procedure are ho have clinically localized tu9nfined to the prostate, 2.0 cm : on palpation, and have Glealess (Table I). lould be less than 60 cc in voltent is feasible in patients who ous transurethral resection of rare were 20 patients who had to relieve obstructive syrupand ~ pauents were originally diagnosed ign .....g P rostat e carcinoma as a result of reir apparently benign disease. We also patients who had local recurrences i~tl radical retropubic prostatectomy. Were 3 patients who had previously ine external beam irradiation and 2 who d iodine-125 implants p e r f o r m e d t h e suprapubie approach. These 5 paad Signs of local tumor progression but ~nee of metastatic disease. Six patients i~ived prior antiandrogen therapy and isidered t() be candidates for an implant fheir tumors were progressive locally, lay:had no indication "of metastases. i f t ~ patients underwent the standard ion to determine their prostate cancer ~his inetuded a bone scan, eomputerized ~Ph~ (CT) scan of the abdomen and prostate acid phosphatase (PAP), and ~sp6cific anti g en ( PSA)• Gleason scores .....: ...... ~orded for all of the original biopsy ~S, :Scores of 1 to 3 were present in 30 iQf the patients, 4 to 7 in 60 percent, and ts who meet these criteria tical prostatectomy which preferable therapy for the Many patients did not or had a medical problem ~tured by Theragenics Corporation,
1991
/
TABLEI.
OptimumcandidatesJor implant therapy
Stage A1, A2, B1, B2 Refused or medically ineligible for radical prostatectomy Prostate volume < 60 cc Tumor volume < 4 cc TABLEII.
Planningsessionfor prostate volumetrics
Volume specification Volume dosimetry Construct 3-dimensional isodose curves Calculate number of seeds required and their placement within the prostate which made them a poor risk for surgery. These same patients are also candidates for external beam radiation therapy. When offered the choice between external beam radiotherapy and ultrasound-guided interstitial therapy, the majority of the patients selected the radioactive implants.
Pre-therapy planning When a patient has selected the ultrasoundguided implant procedure, prostate volumetrics are obtained (Table II). This procedure involves the transrectal ultrasound measurement of the prostate to determine the location and number of the seeds that will be placed. This is done by measuring the volume of the prostate at 0.5-cm intervals beginning at the base and continuing to the apex. The seeds are ordered, and the patient is scheduled for the implant. If a large amount of the prostate is situated behind the pubic bone, as determined by the CT scan, adequate implantation may not be feasible. In some instances the prostate can be reduced with antiandrogen therapy, and in some patients we have elected to drill holes through the pubis in order to place the needles.
Implant technique (Table HI) The procedure can be done using regional, local, or general anesthesia. The patient is placed in the lithotomy position, the bladder is drained, the scrotum is sewn to the lower abdomen to obtain exposure of the perineum, and the ultrasound probe is placed in the rectum. A template is attached to the probe which is fixed in position so that the image corresponds to the site at the base of the prostate which was identified on the volumetric study. This is usually at the level of the seminal vesicles. Two needles are placed through the template into the prostate to
VOLUME XXXVIII, NUMBER 4
373
1. 2. 3. 4. 5. 6. 7. 8.
TABLEIII. Implant technique Outpatient procedure Lithotomy position; spinal or local anesthesia Transrectal ultrasound image positioned at seminal vesicles to match "planning" images Template secured to rectal probe Stabilizing needles 17-gauge needles inserted through template at predetermined sites to appropriate depth using ultrasound guidance Mick applicator used to place seeds through needles into prostate at previously calculated intervals; fluoroscopic control can be used Needles are removed and patient is discharged after recovering from anesthesia
stabilize its position. These needles are usually not loaded with seeds. Needles are placed in successive rows of the template according to a chart prepared by the radiation physicist (Fig.
the pelvis is obtained several days later late the dosimetry. The average numbel implanted was 76.6 (range 13 to 135) individual seed activity was 1.2 to 2.0q Palladium-103 emits photons in the 20-23 KeV with a half-life of sevente The tumor doses were calculated w i t h tenuation correction to have average (range from 150 Gy to 190 Gy) delivered o~1 period of 6 half-lives. Using a 1.8 m C i seed, the total dose deli~i~~ to the tissue around each seed after one hlu~r~]~ days is 25,000 eGy. The dose to the re6[u]~ ~ 11,000 to 13,000 cGy. : ~; Patients are seen at three-month interv~ measurement of their PSA, to have prost~i trasonography to measure their prostatel '~i have palpation of their prostate. Prosta[~!] sies are done at twelve, eighteen, and t ~'~ four months. Bone scans are done yearlyi~
1). The radiation oncologist places the seeds at predetermined intervals and withdraws the needles after all of the seeds have been placed. This is repeated until each row has been implanted. A Mick applicator is used to insert the seeds through the needle. The seeds remain permanently in position. The accurate placement of the needles is insured by ultrasound guidance, and the accuracy of the seed placement can be followed by watching under fluoroscopy. When all of the seeds have been placed, the last needle is removed, followed by removal of the stabilizing needles, the template, and the ultrasound probe. The procedure takes approximately one and one-half hours, and the patient may return home the same day after recovering from the anesthetic. Most patients resume their regular activities within several days. An x-ray film of
•
•
•
4
.
.
.
3
.
.
x
o
•
•
•
x
.
.
.
x
x
.
.
2.xxxxx. l.xxxxx. ABCDEFG FIGURE 1. Model of diagram used to place needles through template and into prostate.
374
Results The patients in this study ha for an average of 11.8 month months). All of the patients have h~ prostate size of greater than 50 prostate size stabilized after si~ PSA levels have returned to creased by more than 50 perc( of the patients, and this has d. months. Not enough time has mine the rate of local or dista~ In the patients who have b twelve months or longer, dista occurred in 1 patient, but the: of cancer in his prostate. Two viously received radiation specimens positive for eanc~ Their prostate size had d, PSAs were less than 2. None of the remaining pa signs of metastases or tumor
Complications The most common problen and urethral irritative sympl oeeurred in 90.3 percent of tt symptoms were severe enoug[ cation in 54.2 percent. These within the first month in th, tients but have lasted as lon months. In 5 patients urinary oped, and they required cath( several days. One patient was
UROLOGY
/
OCTOBER1991
/
VOLUME
IV. Interstitial brachytherapy sources Half-Life 1,604.0 yrs 3.8 d 2.7 d 74.2 d 60.2 d 16.97 d
Average Energy (KeV) 780 780 420 290 28 21
aths and required a transurethral rete is now voiding without difficulty. been intermittent gross hematuria in ttients during the first three to four aplications have been infrequent. ..had severe diarrhea and pain. e patients had rectal ulcerations [within three months. There have mic symptoms, no reports of impoand no incontinence. Patient acthis procedure has been extraor1. Most patients have been able to ;ir regular activities within a few vere 8 patients who were hospitalized ~ation because of associated medical a n d it was thought safer to have ain in the hospital overnight. Comment ,~sic principle in radioisotope implantat o maximize the tumor dose while ng the dose to normal tissue. The raie can be temporary, such as iridium~rmanent such as gold-98, iodine-125, [ium-103 (Table IV). Iodine has an 1:28--32 KeV, a half-life of sixty days, seof 160 Gy delivered to total decay if:Palladium-103 emits photons in the i0~23 KeV with a half-life of seventeen delivers an average of 170 Gy in a typ:~a[epermanent implant. ~iative biologic effectiveness of the ~ optimized at these lower dose rates. ~ has the theoretical advantage of a ~se rate over a shorter period of time, !i~;nknown if this will translate into a ifg( ive tumor dose for prostate carWe chose to treat all 80 patients in this itch Palladium-103. $~hnd,guided prostate implant therapy ~ne,125 or Palladium-103 represents a imi6f management for patients with '~an,eonfined prostate cancer. This represents an alternative to standard
TABLEV. Comparison between iodine-125 (~51) and palladium-103 (l°3Pd) Half-life Radiation dose Average energy Initial dose rate
1251
103pd
60 days 16,000 eGy 28 KeV 5-10 eGy/hr
17 days 17,000 cGy 21 KeV 20-30 cGy/hr
radiation therapy and for patients who are unable to accept surgery or are unsuitable for radical prostatectomy. There are no data to suggest that the efficacy of the implant procedure will equal or exceed either of the other forms of therapy. From a theoretical consideration, implant therapy should approach external beam irradiation in efficacy, and experience has already indicated that complications and morbidity have not been severe. The advantages of the ultrasound-guided technique as compared to conventional radiation therapy include the ability to obtain excellent localization and distribution of the seeds, a treatment which can be done at a single outpatient visit, minimal systemic side effects, few severe local side effects, and rapid shrinkage of the prostate. In our experience, prostate size and PSA levels decrease more rapidly with implant therapy when compared to external beam irradiation. Prostate size has stabilized in six to nine months. PSA values returned to normal or diminished by more than 50 percent in 97 percent of the patients who were treated within six months. It is too early in our experience to determine local failure rates. Blasko and Ragde 11 have reported their results in 357 patients followed for an average of twenty-four months. They have had 4 failures in 220 patients treated with iodine-125 alone, 4 failures in 84 patients treated with a combination of iodine-125 and external beam irradiation, and no failures in 53 patients treated with Palladium-103 with or without additional external beam irradiation. Only 1 of the 8 failures was related to local disease progression alone. One failure was a combination of distant metastasis and local progression, and the remainder were distant metastases alone. They noted that distant failure was accomplished by a significant rise in PSA over a sixmonth period. Positive prostate biopsy specimens were found in 15.9 percent of those treated with iodine-125 alone and 21 percent of those treated with iodine-125 and external
! OCTOBER 1991 / VOLUMEXXXVIII, NUMBER 4
375
beam radiation therapy at sixteen to twentyfour months of follow-up. The duration of follow-up is too brief, and the number of patients who have been treated with ultrasound-guided prostate implants is too small to permit an endorsement of this procedure as a standard form of therapy for prostate cancer. For properly selected patients it represents an alternative to radical prostatectomy or external beam radiation therapy. As experience is gained, a better definition of the most suitable candidates will be obtained, and the efficacy of this therapy in treating localized prostate carcinoma will be determined. 1304 15th Street, Suite 200 Santa Moniea, California 90404 (DR. BROSMAN) References 1. Flocks RH, Kerr HD, and Elkins HB: Treatment of carcinoma of the prostate by interstitial radiation with radioactive gold, J Urol {}8:510 (1952). 2. Hilaris BS, Whitmore WF, Batata MA, and Grabstald H:
376
Radiation therapy and pelvic node dissection in the . . . . '-. of cancer of the prostate, in Hilaris BS (Ed): Handbook oc ~.: el~ tlal Brachytherapy, Boston, Acton, 1975, p 2 1 9 . . :• ~uters~i. : ~ 3. Sogani PC, DeCrosse JJ, and Montie J: prostate. Treatment with pelvic lymphadene 125 implants, Clin Bull 9:24 (1979). 4. Nori D, and Hflaris BS: Brachytherapy i prostate cancer, Endocuriether Hypertherm C 5. Hilaris BS, Fuks Z, and Nori D: Interst Prostate Cancer. Report of Ten-Year Results. diotherapy Techniques in Brachytherapy, Berli: 1990, p 86. 6. Nori D, Hilaris BS, and Peschel R: Prosta tial Brachytherapy, New York, Raven Press, L 7. DeBlasio DS, Hilaris BS, and Nori D: Pc1 implantation of prostatic cancer in the - - pertherm Oncol 4:193 (1988). 8. Holm HH, et al: Transperineal ioc in prostatic cancer guided by transreet; 130:283 (1983). 9. Blasko JC, Ragde H, and Schuma cutaneous iodine-125 implantation for transrectal ultrasound and template gui pertherm Oncol 3:131 (1987). 10. Ragde H, Blasko JC, and Schum~ ultrasound in transperineal iodine-125 cer: methodology, J Endourol 3:209 (1 11. Blasko JC, and Ragde H: Result., guided implantation of 12sI and l°3pd in at Swedish Hospital Conference, SeattJ
UROLOGY
/
OCTOBER 1991
/
VOLUME XXXVIIL : ~d~(.~
TRANSRECTAL U L T R A S O U N D - G U I D E D INTERSTITIAL RADIATION THERAPY FOR LOCALIZED PROSTATE CANCER STANLEY A. BROSMAN, M.D. KENNETH TOKITA, M.D.
From the Departments of Surgery/Urology and Radiation Oneology, St. John's Hospital and Health Center, Santa Monica, California ABSTRACT--The use of interstitial implants for the treatment of low-stage prostate cancer using transrectal ultrasound guidance is evaluated in 80 -patients. This outpatient procedure involves the placement of needles through a template and into the prostate. Ultrasound guidance is used to place the needles into a preselected location. The needles are loaded with a radioactive source. In this study Palladium-103 was utilized. This technique allows accurate and complete seeding of the prostate. There was a 50 percent or greater decrease in prostate size in all of the patients who were implanted. Prostate-specific antigen (PSA) levels became normal or decreased by more than 50 percent in 97 percent of the patients. Most patients experienced urethral irritative symptoms which lasted up to five months, but none of the patients experienced rectal symptoms lasting longer than a month. The mean follow-up is 11.8 months which is too brief to ascertain the effectiveness of this therapy. The method appears to be safe and may represent an alternative to external beam irradiation.
Radiation therapy is an important option in the management of patients with prostatic cancer. This form of therapy is particularly effective when the cancer is of low volume and confined to the prostate. To enhance the effectiveness of radiotherapy, investigators at the University of Iowa began implanting radioactive gold seeds into the prostate in 1952.1 This technique did not gain wide popularity, but physicians at Memorial Sloan-Kettering Cancer Center in New York reevaluated the use of this type of radioactive seed implant therapy for prostate cancer in 1970. They implanted iodine-125 seeds into the prostate using a suprapubic operative approach. 2 Although the prostate was visible, there was a problem in obtaining good distribution of the seeds. This led to a high rate of tumor recurrence and progression, a The procedure was abandoned by most urologists and radiation therapists but the brachytherapists who were initially involved at Memorial Sloan372
Kettering Cancer Cente: and improving this meth Two important lessons early experience. F i r s t , plant radioactive seeds J relative safety; secon diotherapy could destroy ior of prostate cancer ce] solved was how to obtail distribution of the radial the prostate. The develo]; trasonography represent, sary to permit the accu dioactive seeds into the added advantage of not l tervention. In 1983 Holm et al. s their experience with placed perineally throt transrectal ulrasound gui and Schumacher9,1° mo
UROLOGY
/
OCTOBER 1991
/
VC
an treating patients in 1985. Palladiumame available in 1988, and several med~ters have begun to use this isotope to 0state cancer. ~cribe the technical features of radioacd implantation and the complications dd with this therapy in 80 patients who eared with Palladium-103. * Material and Methods
~tion candidates for this procedure are ho have clinically localized tu9nfined to the prostate, 2.0 cm : on palpation, and have Glealess (Table I). lould be less than 60 cc in voltent is feasible in patients who ous transurethral resection of rare were 20 patients who had to relieve obstructive syrupand ~ pauents were originally diagnosed ign .....g P rostat e carcinoma as a result of reir apparently benign disease. We also patients who had local recurrences i~tl radical retropubic prostatectomy. Were 3 patients who had previously ine external beam irradiation and 2 who d iodine-125 implants p e r f o r m e d t h e suprapubie approach. These 5 paad Signs of local tumor progression but ~nee of metastatic disease. Six patients i~ived prior antiandrogen therapy and isidered t() be candidates for an implant fheir tumors were progressive locally, lay:had no indication "of metastases. i f t ~ patients underwent the standard ion to determine their prostate cancer ~his inetuded a bone scan, eomputerized ~Ph~ (CT) scan of the abdomen and prostate acid phosphatase (PAP), and ~sp6cific anti g en ( PSA)• Gleason scores .....: ...... ~orded for all of the original biopsy ~S, :Scores of 1 to 3 were present in 30 iQf the patients, 4 to 7 in 60 percent, and ts who meet these criteria tical prostatectomy which preferable therapy for the Many patients did not or had a medical problem ~tured by Theragenics Corporation,
1991
/
TABLEI.
OptimumcandidatesJor implant therapy
Stage A1, A2, B1, B2 Refused or medically ineligible for radical prostatectomy Prostate volume < 60 cc Tumor volume < 4 cc TABLEII.
Planningsessionfor prostate volumetrics
Volume specification Volume dosimetry Construct 3-dimensional isodose curves Calculate number of seeds required and their placement within the prostate which made them a poor risk for surgery. These same patients are also candidates for external beam radiation therapy. When offered the choice between external beam radiotherapy and ultrasound-guided interstitial therapy, the majority of the patients selected the radioactive implants.
Pre-therapy planning When a patient has selected the ultrasoundguided implant procedure, prostate volumetrics are obtained (Table II). This procedure involves the transrectal ultrasound measurement of the prostate to determine the location and number of the seeds that will be placed. This is done by measuring the volume of the prostate at 0.5-cm intervals beginning at the base and continuing to the apex. The seeds are ordered, and the patient is scheduled for the implant. If a large amount of the prostate is situated behind the pubic bone, as determined by the CT scan, adequate implantation may not be feasible. In some instances the prostate can be reduced with antiandrogen therapy, and in some patients we have elected to drill holes through the pubis in order to place the needles.
Implant technique (Table HI) The procedure can be done using regional, local, or general anesthesia. The patient is placed in the lithotomy position, the bladder is drained, the scrotum is sewn to the lower abdomen to obtain exposure of the perineum, and the ultrasound probe is placed in the rectum. A template is attached to the probe which is fixed in position so that the image corresponds to the site at the base of the prostate which was identified on the volumetric study. This is usually at the level of the seminal vesicles. Two needles are placed through the template into the prostate to
VOLUME XXXVIII, NUMBER 4
373
1. 2. 3. 4. 5. 6. 7. 8.
TABLEIII. Implant technique Outpatient procedure Lithotomy position; spinal or local anesthesia Transrectal ultrasound image positioned at seminal vesicles to match "planning" images Template secured to rectal probe Stabilizing needles 17-gauge needles inserted through template at predetermined sites to appropriate depth using ultrasound guidance Mick applicator used to place seeds through needles into prostate at previously calculated intervals; fluoroscopic control can be used Needles are removed and patient is discharged after recovering from anesthesia
stabilize its position. These needles are usually not loaded with seeds. Needles are placed in successive rows of the template according to a chart prepared by the radiation physicist (Fig.
the pelvis is obtained several days later late the dosimetry. The average numbel implanted was 76.6 (range 13 to 135) individual seed activity was 1.2 to 2.0q Palladium-103 emits photons in the 20-23 KeV with a half-life of sevente The tumor doses were calculated w i t h tenuation correction to have average (range from 150 Gy to 190 Gy) delivered o~1 period of 6 half-lives. Using a 1.8 m C i seed, the total dose deli~i~~ to the tissue around each seed after one hlu~r~]~ days is 25,000 eGy. The dose to the re6[u]~ ~ 11,000 to 13,000 cGy. : ~; Patients are seen at three-month interv~ measurement of their PSA, to have prost~i trasonography to measure their prostatel '~i have palpation of their prostate. Prosta[~!] sies are done at twelve, eighteen, and t ~'~ four months. Bone scans are done yearlyi~
1). The radiation oncologist places the seeds at predetermined intervals and withdraws the needles after all of the seeds have been placed. This is repeated until each row has been implanted. A Mick applicator is used to insert the seeds through the needle. The seeds remain permanently in position. The accurate placement of the needles is insured by ultrasound guidance, and the accuracy of the seed placement can be followed by watching under fluoroscopy. When all of the seeds have been placed, the last needle is removed, followed by removal of the stabilizing needles, the template, and the ultrasound probe. The procedure takes approximately one and one-half hours, and the patient may return home the same day after recovering from the anesthetic. Most patients resume their regular activities within several days. An x-ray film of
•
•
•
4
.
.
.
3
.
.
x
o
•
•
•
x
.
.
.
x
x
.
.
2.xxxxx. l.xxxxx. ABCDEFG FIGURE 1. Model of diagram used to place needles through template and into prostate.
374
Results The patients in this study ha for an average of 11.8 month months). All of the patients have h~ prostate size of greater than 50 prostate size stabilized after si~ PSA levels have returned to creased by more than 50 perc( of the patients, and this has d. months. Not enough time has mine the rate of local or dista~ In the patients who have b twelve months or longer, dista occurred in 1 patient, but the: of cancer in his prostate. Two viously received radiation specimens positive for eanc~ Their prostate size had d, PSAs were less than 2. None of the remaining pa signs of metastases or tumor
Complications The most common problen and urethral irritative sympl oeeurred in 90.3 percent of tt symptoms were severe enoug[ cation in 54.2 percent. These within the first month in th, tients but have lasted as lon months. In 5 patients urinary oped, and they required cath( several days. One patient was
UROLOGY
/
OCTOBER1991
/
VOLUME
IV. Interstitial brachytherapy sources Half-Life 1,604.0 yrs 3.8 d 2.7 d 74.2 d 60.2 d 16.97 d
Average Energy (KeV) 780 780 420 290 28 21
aths and required a transurethral rete is now voiding without difficulty. been intermittent gross hematuria in ttients during the first three to four aplications have been infrequent. ..had severe diarrhea and pain. e patients had rectal ulcerations [within three months. There have mic symptoms, no reports of impoand no incontinence. Patient acthis procedure has been extraor1. Most patients have been able to ;ir regular activities within a few vere 8 patients who were hospitalized ~ation because of associated medical a n d it was thought safer to have ain in the hospital overnight. Comment ,~sic principle in radioisotope implantat o maximize the tumor dose while ng the dose to normal tissue. The raie can be temporary, such as iridium~rmanent such as gold-98, iodine-125, [ium-103 (Table IV). Iodine has an 1:28--32 KeV, a half-life of sixty days, seof 160 Gy delivered to total decay if:Palladium-103 emits photons in the i0~23 KeV with a half-life of seventeen delivers an average of 170 Gy in a typ:~a[epermanent implant. ~iative biologic effectiveness of the ~ optimized at these lower dose rates. ~ has the theoretical advantage of a ~se rate over a shorter period of time, !i~;nknown if this will translate into a ifg( ive tumor dose for prostate carWe chose to treat all 80 patients in this itch Palladium-103. $~hnd,guided prostate implant therapy ~ne,125 or Palladium-103 represents a imi6f management for patients with '~an,eonfined prostate cancer. This represents an alternative to standard
TABLEV. Comparison between iodine-125 (~51) and palladium-103 (l°3Pd) Half-life Radiation dose Average energy Initial dose rate
1251
103pd
60 days 16,000 eGy 28 KeV 5-10 eGy/hr
17 days 17,000 cGy 21 KeV 20-30 cGy/hr
radiation therapy and for patients who are unable to accept surgery or are unsuitable for radical prostatectomy. There are no data to suggest that the efficacy of the implant procedure will equal or exceed either of the other forms of therapy. From a theoretical consideration, implant therapy should approach external beam irradiation in efficacy, and experience has already indicated that complications and morbidity have not been severe. The advantages of the ultrasound-guided technique as compared to conventional radiation therapy include the ability to obtain excellent localization and distribution of the seeds, a treatment which can be done at a single outpatient visit, minimal systemic side effects, few severe local side effects, and rapid shrinkage of the prostate. In our experience, prostate size and PSA levels decrease more rapidly with implant therapy when compared to external beam irradiation. Prostate size has stabilized in six to nine months. PSA values returned to normal or diminished by more than 50 percent in 97 percent of the patients who were treated within six months. It is too early in our experience to determine local failure rates. Blasko and Ragde 11 have reported their results in 357 patients followed for an average of twenty-four months. They have had 4 failures in 220 patients treated with iodine-125 alone, 4 failures in 84 patients treated with a combination of iodine-125 and external beam irradiation, and no failures in 53 patients treated with Palladium-103 with or without additional external beam irradiation. Only 1 of the 8 failures was related to local disease progression alone. One failure was a combination of distant metastasis and local progression, and the remainder were distant metastases alone. They noted that distant failure was accomplished by a significant rise in PSA over a sixmonth period. Positive prostate biopsy specimens were found in 15.9 percent of those treated with iodine-125 alone and 21 percent of those treated with iodine-125 and external
! OCTOBER 1991 / VOLUMEXXXVIII, NUMBER 4
375
beam radiation therapy at sixteen to twentyfour months of follow-up. The duration of follow-up is too brief, and the number of patients who have been treated with ultrasound-guided prostate implants is too small to permit an endorsement of this procedure as a standard form of therapy for prostate cancer. For properly selected patients it represents an alternative to radical prostatectomy or external beam radiation therapy. As experience is gained, a better definition of the most suitable candidates will be obtained, and the efficacy of this therapy in treating localized prostate carcinoma will be determined. 1304 15th Street, Suite 200 Santa Moniea, California 90404 (DR. BROSMAN) References 1. Flocks RH, Kerr HD, and Elkins HB: Treatment of carcinoma of the prostate by interstitial radiation with radioactive gold, J Urol {}8:510 (1952). 2. Hilaris BS, Whitmore WF, Batata MA, and Grabstald H:
376
Radiation therapy and pelvic node dissection in the . . . . '-. of cancer of the prostate, in Hilaris BS (Ed): Handbook oc ~.: el~ tlal Brachytherapy, Boston, Acton, 1975, p 2 1 9 . . :• ~uters~i. : ~ 3. Sogani PC, DeCrosse JJ, and Montie J: prostate. Treatment with pelvic lymphadene 125 implants, Clin Bull 9:24 (1979). 4. Nori D, and Hflaris BS: Brachytherapy i prostate cancer, Endocuriether Hypertherm C 5. Hilaris BS, Fuks Z, and Nori D: Interst Prostate Cancer. Report of Ten-Year Results. diotherapy Techniques in Brachytherapy, Berli: 1990, p 86. 6. Nori D, Hilaris BS, and Peschel R: Prosta tial Brachytherapy, New York, Raven Press, L 7. DeBlasio DS, Hilaris BS, and Nori D: Pc1 implantation of prostatic cancer in the - - pertherm Oncol 4:193 (1988). 8. Holm HH, et al: Transperineal ioc in prostatic cancer guided by transreet; 130:283 (1983). 9. Blasko JC, Ragde H, and Schuma cutaneous iodine-125 implantation for transrectal ultrasound and template gui pertherm Oncol 3:131 (1987). 10. Ragde H, Blasko JC, and Schum~ ultrasound in transperineal iodine-125 cer: methodology, J Endourol 3:209 (1 11. Blasko JC, and Ragde H: Result., guided implantation of 12sI and l°3pd in at Swedish Hospital Conference, SeattJ
UROLOGY
/
OCTOBER 1991
/
VOLUME XXXVIIL : ~d~(.~
