Radiation therapy in the definitive treatment of localized carcinoma of the prostate

Sexual function after external-beam radiotherapy for prostate cancer: What do we know?

Quality of life in general and sexual functioning in particular have become very important in cancer patients. Due to modern surgical techniques, improved quality of drugs for chemotherapy and very modern radiation techniques, more patients can be successfully treated without largely compromising sexual functioning. One can assume that because of the life-threatening nature of cancer, sexual activity is not important to patients and their partners, but this is not true. Prostate cancer has become the most common non-skin malignant neoplasm in older men in Western countries. In this paper, we discuss the various methods used to evaluate erectile and sexual dysfunction and the definition of potency. Data on the etiology of erectile dysfunction after external-beam radiotherapy for prostate cancer is reviewed, and the literature is been summarized. Patients should be offered sexual counseling and informed about the availability of effective treatments for erectile dysfunction, such as sildenafil, intracavernosal injection, and vacuum devices. Cancer affects quality of life and sexual function. The challenge for oncologists is to address this with compassion.

Sexual (dys)function after radiotherapy for prostate cancer: a review

PURPOSE

Prostate cancer has become the most common nonskin malignant neoplasm in older men in Western countries. As treatment efficacy has improved, issues related to posttherapy quality of life and sexual functioning have become more important.

METHODS AND MATERIALS

We discuss the various methods used to evaluate erectile and sexual dysfunction and the definition of potency. The etiologies of erectile dysfunction after external beam radiotherapy and brachytherapy for prostate cancer are also reviewed. The literature is summarized, and comparative studies of radiation and surgery are surveyed briefly.

RESULTS

Rates of erectile dysfunction vary from 6 to 84% after external beam radiotherapy and from 0 to 51% after brachytherapy. In most of the studies, the analysis is retrospective, the definition of erectile dysfunction is not clear, only one question about sexual functioning is asked, and nonvalidated instruments are used. The etiology of erectile dysfunction after radiation for prostate cancer is not completely understood.

CONCLUSIONS

Because erectile function is only one component of sexual function, it is necessary to assess sexual desire, satisfaction, frequency of intercourse, and other such factors when evaluating the effects of therapy. Patients should be offered sexual counseling and informed about the availability of effective treatments for erectile dysfunction, such as sildenafil, intracavernosal injection, and vacuum devices.

In the radiotherapy of prostate cancer, technique determines the doses to the penile structures

For 11 consecutive prostate cancer patients undergoing three-dimensional conformal radiotherapy (3DCRT) in our institution, penile structures (PNS) were outlined in CT images obtained for treatment planning purposes. Dose-volume histograms (DVHs) were compared in order to study dose-volume relations for three techniques: 4FLD, an axial coplanar, four-field box technique; 6FLD, a six-field coplanar technique; and 4NAX, a coplanar but non-axial, four-field technique. All three techniques delivered equal doses to the planning target volumes (PTV). Our statistical analyses strongly indicate that the three techniques can be ranked as 6FLD better than 4FLD (and 4FLD better than 4NAX) as far as irradiating PNS volume during treatment of prostate cancer (PC) is concerned. For each technique, there is a "spread" owing to differences in patient anatomy and/or target size, position, and extent, but each technique has a similar "profile" or "shape" distinct from other techniques. Whether irradiating smaller volumes of PNS will influence the sexual potency outcome remains to be demonstrated. However, PNS should be considered as another critical structure in addition to rectum, bladder and femoral heads in the radiotherapy (RT) of PC, especially in 3DCRT dose escalation studies. Sexual potency outcomes can be correlated to dose-volume relations in the future and this will help refine radiotherapy techniques further.

Sexual function following radical radiotherapy for bladder cancer

BACKGROUND AND PURPOSE

The effect of radical radiotherapy (RT) for bladder cancer on sexual function has not been previously investigated. The current study was designed as a pilot to assess sexual function in males pre- and post-radiotherapy.

MATERIALS AND METHODS

An anonymous questionnaire was devised to examine the following sexual domains: libido, frequency of sexual function, erectile capacity, orgasm and ejaculation in the 6 months prior to radiotherapy and following treatment. Serum testosterone, FSH and LH were measured in 10 patients.

RESULTS

Eighteen patients completed the questionnaire from 10 to 56 months following irradiation, 13 of whom were able to achieve an erection prior to RT. Over half of these patients noted a decline in the quality of erections after RT, with a similar proportion noting decreased libido and frequency of sexual activity. Three patients lost the ability to have any erections whatsoever. Of the 10 patients retaining erectile capacity, three noted reduced frequency of early morning erections suggesting a physical aetiology, five had decreased frequency of ejaculation and four had reduced intensity of orgasms. Seventy-one percent (12/17) felt their sex life was worse following RT but only 56% (9/16) were concerned about the deterioration. Testosterone levels were normal in all but one patient.

CONCLUSIONS

Radical RT to the bladder can cause a decrease in sexual function in males.

Dose escalation with three-dimensional conformal radiation therapy affects the outcome in prostate cancer

PURPOSE

Three-dimensional conformal radiation therapy (3D-CRT) is a technique designed to deliver prescribed radiation doses to localized tumors with high precision, while effectively excluding the surrounding normal tissues. It facilitates tumor dose escalation which should overcome the relative resistance of tumor clonogens to conventional radiation dose levels. The present study was undertaken to test this hypothesis in patients with clinically localized prostate cancer.

METHODS AND MATERIALS

A total of 743 patients with clinically localized prostate cancer were treated with 3D-CRT. As part of a phase I study, the tumor target dose was increased from 64.8 to 81 Gy in increments of 5.4 Gy. Tumor response was evaluated by post-treatment decrease of serum prostate-specific antigen (PSA) to levels of < or = 1.0 ng/ml and by sextant prostate biopsies performed > or = 2.5 years after completion of 3D-CRT. PSA relapse-free survival was used to evaluate long-term outcome. The median follow-up was 3 years (range: 1-7.6 years).

RESULTS

Induction of an initial clinical response was dose-dependent, with 90% of patients receiving 75.6 or 81.0 Gy achieving a PSA nadir < or = 1.0 ng compared with 76% and 56% for those treated with 70.2 Gy and 64.8 Gy, respectively (p < 0.001). The 5-year actuarial PSA relapse-free survival for patients with favorable prognostic indicators (stage T1-2, pretreatment PSA < or = 10.0 ng/ml and Gleason score < or = 6) was 85%, compared to 65% for those with intermediate prognosis (one of the prognostic indicators with a higher value) and 35% for the group with unfavorable prognosis (two or more indicators with higher values) (p < 0.001). PSA relapse-free survival was significantly improved in patients with intermediate and unfavorable prognosis receiving > or = 75.6 Gy (p < 0.05). A positive biopsy at > or = 2.5 years after 3D-CRT was observed in only 1/15 (7%) of patients receiving 81.0 Gy, compared with 12/25 (48%) after 75.6 Gy, 19/42 (45%) after 70.2 Gy, and 13/23 (57%) after 64.8 Gy (p < 0.05).

CONCLUSIONS

The data provide evidence for a significant effect of dose escalation on the response of human prostate cancer to irradiation and defines new standards for curative radiotherapy in this disease.

Potency probability following conformal megavoltage radiotherapy using conventional doses for localized prostate cancer

PURPOSE

Impotence is a familiar sequela of definitive external beam radiation therapy (EBRT) for localized prostate cancer; however, nerve-sparing radical prostatectomy (NSRP) has offered potency rates as high as 70% for selected for patients in several large series. To the authors' knowledge, age and stage-matched comparisons between the effects of EBRT and NSRP upon the normal age trend of impotence have not been performed. Herein, we report the change in potency over time in an EBRT-treated population, determine the significantly predisposing health factors affecting potency in this population, and compare age and stage-matched potency rates with those of normal males and prostatectomy patients.

METHODS AND MATERIALS

Our results are obtained from a retrospective study of 114 patients ranging in age from 52 to 85 (mean, 68) who were diagnosed with clinical stages A-C C (T1-T4N0M0) prostate cancer and then treated conformally with megavoltage x-rays to 6500-7000 cGy (180-200 cGy per fraction) using the four-field box technique. Information concerning pre-RT potency, medical and surgical history, and medications was documented for each patient as was time of post-RT change in potency during regular follow-up. The median follow-up time was 18.5 months.

RESULTS

The actuarial probability of potency for all patients gradually decreased throughout post-RT follow-up. At months 1, 12, 24, and 36, potency rates were 98, 92, 75, and 66%, respectively. For those patients who became impotent, the median time to impotence was 14 months. Factors identified from logistic regression analysis as significant predictors of post-EBRT impotence include pre-EBRT partial potency (p < 0.001), vascular disease (p < 0.001), and diabetes (p = 0.003). Next, an actuarial plot of potency probability to patient age for the EBRT-treated population was compared to that obtained from the Massachusetts Male Aging Study of normal males. The two curves were not significantly different (logrank test, p = 0.741) between ages 50 and 65. Finally, potency probability after follow-up of 1 year or more in EBRT-treated patients was stratified by age and substratified by clinical stage and then compared to similarly stratified potencies for patients treated with NSRP. The prostatectomy data were derived from the pooled data of six large (total n, 952), independent series conducted at academic centers. For patients older than 70 years, 79.1% of EBRT patients and 32.9% of NSRP patients remained potent after treatment. For patients with stage B2 disease, 75.0% of EBRT patients and 49.3% of NSRP patients remained potent after treatment. Overall EBRT patient potency was 76.1% vs. 66.2% for NSRP patients.

CONCLUSIONS

1) By 36 months after completion of EBRT for localized prostate cancer, fully one-third of all patients becomes impotent; however, for patients younger than 70 years, the probability of impotence does not depart significantly from that for normal males. 2) In the EBRT-treated population, pre-EBRT partial potency, vascular disease, and diabetes are the most significant predispositions to the development of impotence. Patients with these predispositions, though, do not become impotent significantly earlier than other patients. 3) When comparing age and stage-stratified potency rates for EBRT and NSRP patients, potency is roughly equal for both modalities for most age and stage groups; however, for patients older than 70 years or with stage B2 disease, EBRT offers notably higher posttreatment potency rates than NSRP. Thus, for the treatment of localized prostate cancer, EBRT may not affect the normal age trend of impotence in younger patients and may induce impotence less frequently than NSRP in older patients or in patients with later stage disease.

Self-assessed sexual function after pelvic irradiation for prostate carcinoma. Comparison with an age-matched control group

BACKGROUND

Treatment of localized prostate carcinoma is often accompanied by disturbances in sexual function. The patient's own opinion and experience with these problems can be of great importance for his quality of life. In men older than 50 years, disturbances in sexual function are common. Treatment such as radiotherapy (RT), which can induce sexual dysfunction, should be evaluated in relation to the problems in an age-matched population without prostate carcinoma.

METHODS

Sexual function was evaluated with a self-assessment questionnaire using linear-analogue scales. The questionnaire was sent to 199 patients with prostate carcinoma, median age 71 years (range, 51-86 years), who had received pelvic RT with curative intent and to 200 age-matched men in northern Sweden. Mean follow-up time after RT was 48 months (range, 24-56 months).

RESULTS

The response rate was high: 141 (71%) and 181 (91%) in the control and patient groups, respectively. Field reduction and treatment pause during RT was not associated with decreased problems in the patient groups. A failure to achieve erection was indicated in 12% of the control subjects, 56% of the patients who had received (RT only) and 87% of the RT + castration (RT + A) patients. In general, patients < 70 years treated with RT+A indicated more sexual problems than the RT only patients < 70 years. There was a strong negative correlation between age and sexual problems in the RT + A < 70 years group. However, in patients < 70 years, sexual activity after RT only, was not significantly different from the age-matched control population.

CONCLUSIONS

Patients with prostate carcinoma treated with RT only indicated higher levels of sexual dysfunction than age-matched controls. This was most obvious in patients younger than 70 years, although their sexual activity was comparable to age-matched controls. The addition of castration to RT tended to increase sexual problems, especially in patients < 70 years. In men between 70 and 74 years, the maintenance of sexual function seems to be very susceptible to disturbances. For patients older than 74 years, decreased sexual function was not perceived as such a significant problem, despite abolished desire and erection.

Treatment related sequelae following external beam radiation for prostate cancer: a review with an update in patients with stages T1 and T2 tumor

The primary goal of radical radiation therapy in men with localized prostate carcinoma is cure and a secondary but important goal is to achieve cure without treatment related sequelae, such as loss of continence, rectal injury, loss of potency and the need for castration. A literature review of 2,611 men undergoing irradiation for all stages of localized prostatic carcinoma documented a 0.2% incidence of treatment related mortality, 1.9% severe complications, 0.9% incontinence and 33 to 60% maintenance of full potency 5 or more years after treatment. A separate analysis was made of 331 patients with only early tumors (stages T1 and T2) treated with conventional external beam radiation therapy to doses of 63 to 74 Gy. from 2 individual centers (Massachusetts General Hospital and M.D. Anderson Hospital) and 1 multi-institutional group (Radiation Therapy Oncology Group). Median followup was 6.1 years; however, in 2 series followup ranged to 14 years. This analysis revealed frequencies of treatment associated sequelae of 0% for mortality, 0% severe complications, 0.4% urinary incontinence, 5.4% genitourinary structures (1.2% persisting), 5.1% hematuria (0.9% persisting) and 5.4% rectal bleeding (0.6% persisting). This composite analysis of men undergoing irradiation for stages T1 and T2 tumors with conventional fractionation and doses indicates that acute morbidity is minor and usually transient, severe injury is rare, most late gastrointestinal and genitourinary symptoms of radiation injury are neither permanent nor debilitating, and few symptoms of radiation injury develop beyond 5 years from treatment. These data, combined with the low progression rates (using prostate specific antigen criteria) following irradiation of men with early tumors, further substantiate the primary role of radical radiotherapy in the treatment of surgical risk adversive patients.

Neoadjuvant hormonal therapy and radical prostatectomy for clinical stage C carcinoma of the prostate

OBJECTIVE

To determine whether hormonal therapy prior to radical prostatectomy (neoadjuvant hormonal therapy) leads to improved results in patients with stage C prostate cancer.

PATIENTS AND METHODS

Thirty patients received neoadjuvant hormonal therapy for stage C carcinoma of the prostate. Eighteen patients who responded to treatment subsequently underwent extirpative surgery.

RESULTS

Fourteen of the 30 patients (47%) were diagnosed as being downstaged to clinical stage B disease following therapy. No major complications occurred. Pathology staging revealed only three patients (10%) to have organ-confined disease after radical prostatectomy.

CONCLUSIONS

Neoadjuvant hormonal therapy prior to radical prostatectomy offers little probability of rendering patients with clinical stage C carcinoma of the prostate free of disease. Further investigation of the efficacy of this treatment should be accomplished in randomized trials.

Use of percutaneous transperineal 198Au seeds to treat recurrent prostate adenocarcinoma after failure of definitive radiotherapy

Patients who fail external radiation therapy for prostatic cancer pose a therapeutic challenge. No further external radiation treatment can be delivered safely to the local lesion, although some patients are candidates for salvage surgery. In this study, 31 patients who failed prior external beam radiotherapy received percutaneous transperineal placement of gold seeds (198Au). Initial prostate volume was 17.7 cc and decreased to 10 cc 24 months after 198Au implantation. Of 15 patients biopsied at 12 months after treatment, 4 (27%) were positive, 6 (40%) were negative, and 5 (33%) showed prostate cancer with radiation changes. Two of three patients have died of prostate cancer, with an overall 5-year estimated survival of 67%. Interstitial brachytherapy was found to be an additional well-tolerated treatment modality in this group of 31 patients.

Radiation therapy in prostate cancer: whole pelvis with prostate boost or small field to prostate?

The purpose of this retrospective study is to identify prostate cancer patients who would benefit from pelvic nodes irradiation (whole pelvis) as opposed to the small-field irradiation to the prostate only. Between 1975 and 1983, 126 patients were treated by whole pelvis (4,600-5,000 cGY) with prostate boost (2,000 cGY) radiation (WP + P). Median follow-up was six years and six months. Comparison was made with historic control of 116 patients irradiated at the same institutions between 1971 and 1977 by small field to the prostate (P) to a dose of 7,000-7,500 cGY. There was a significant five-year survival improvement in the current WP + P radiation in Stage C (72% vs 40%, p = 0.0004) and Stage B (92% vs 70%, p = 0.025) but not in Stage A2 patients. However, WP + P radiation significantly improved disease-free survival (DFS) in only well and moderately but not in poorly differentiated carcinoma with a combined well and moderately differentiated five-year DFS of 63 percent compared with the 45 percent in P radiation (p = 0.0228). Local tumor control was significantly improved in WP + P radiation in only Stage C cancers with their local recurrence rate 16 percent as compared with the 34 percent in P radiation (p = 0.0172). Although acute radiation reactions were more frequent in WP + P than P radiation (61% vs 41%, p = 0.0022), chronic radiation morbidity in both series were similar. Thus, whole pelvis with prostate boost radiation should be utilized in Stage B and Stage C cancers as this has shown to increase the survival of the patient without increasing chronic radiation morbidity.

The effect of interstitial hyperthermia on the Dunning prostate tumor model

The effect of hyperthermia was examined on the Dunning prostate tumor model in rats. Hyperthermia was created by heating self-regulating interstitial seeds with an external oscillating magnetic field. The seed alloy was comprised of 70% nickel and 30% copper. One treatment with 50C seeds for two hours did not provide significant delay in tumor growth compared to controls. However, regimens with two treatments separated by either 48 hours or one week did cause significant delay (p = 0.0013 and p = 0.0096, respectively). These results suggest that an interstitial hyperthermia seed may provide an efficacious outpatient therapy for prostate cancer. Further, interstitial hyperthermia may be readily combined with existing radiotherapy with interstitial gold coated seeds to provide additive or synergistic anti-tumor effects.

Late local complications after definitive radiotherapy for prostatic adenocarcinoma

Definitive radiation treatment of prostatic adenocarcinoma has been reported to produce good long-term local disease control, and distant disease failure is almost always associated with good local palliation. We examined late local complications in patients who died with recurrent prostate cancer after definitive radiotherapy as compared to patients treated with hormonal deprivation alone for advanced disease. Between 1979 and 1989 the tumor registry listed 33 men in whom definitive radiotherapy failed documented by bone scan or biopsy and 54 men who were managed with palliative hormonal therapy for noncurable disease. A complication was defined as a local problem requiring a procedure or hospitalization. Overall 23 of the radiotherapy cases (70%) had a local complication as compared to 16 of the patients (30%) who underwent only hormonal therapy. Local complications after radiotherapy included urethral stricture (10 cases), prostatic obstruction (8), hematuria (4), radiation cystitis (3), ureteral obstruction (2) and rectosigmoid radiation injury (4). Local complications after hormonal therapy consisted of prostatic obstruction (11 cases), ureteral obstruction (3) and hematuria (3). The radiotherapy group had 2 urinary and 2 fecal diversions, and the hormonal therapy group had none. In summary, we found a higher risk of late local complications in patients who had recurrence and died with metastatic prostate cancer after definitive radiotherapy, as compared to patients who only received hormonal therapy. These results question the belief that patients with distant disease in whom radiotherapy fails enjoy good long-term local palliation.

The clinical significance of a positive post-irradiation prostatic biopsy without metastases

To define the prognostic value of a post-irradiation prostatic biopsy, the outcome of 203 previously irradiated patients who underwent post-treatment biopsy was analyzed. The majority of patients were selected for biopsy based on an abnormal digital rectal exam or elevated prostate specific antigen. Patients with distant metastases found at the time of biopsy were excluded from further analysis. One hundred thirty-nine (139) of these had a positive biopsy and 64 were negative. Those with a positive biopsy tended to present with more locally-advanced (Stage B2/C) tumors (61%) compared to those with negative biopsies (42%). The 10- and 15-year survival and cause-specific survival from the time of initial presentation were similar for both groups. However, those with a negative biopsy had a more favorable survival and cause-specific survival from the time of post-treatment biopsy and were less likely to develop distant metastases than the positive biopsy group. These data suggest that a positive prostatic biopsy is associated with a greater likelihood of subsequent distant relapse and decreased survival following biopsy relative to patients with negative biopsies. Since a positive post-treatment biopsy is more likely among patients presenting with locally-advanced disease, perhaps more aggressive initial therapy (i.e., interstitial boost or hyperthermia) would benefit this subgroup.

Radiation sensitivity of Copenhagen rat prostatic carcinoma (R3327-AT and R3327-MATLyLu)

The radiosensitivity of two variants of the Dunning Copenhagen rat prostatic tumor R3327 was investigated. The R3327-AT variant, which is a poorly differentiated anaplastic, fast-growing tumor, was irradiated both in vivo and in vitro. Following irradiation, monodispersed cells were plated in vitro and colonies were counted after 7 days. The survival curve of R3327-AT cells irradiated in vivo showed an initial shoulder (Dq-value 0.97 Gy), followed by two exponential parts. The D0-value for the first part of the curve (0-10 Gy) was 2.76 Gy and for the second part of the curve (greater than 10 gy) 9.05 Gy. Extrapolation of the second part of the curve to the Y-axis indicated that the proportion of more radioresistant cells was about 10%. The survival curve for R3327-AT cells irradiated in vitro also suggested the presence of a radioresistant subpopulation, although the proportion was lower (about 3%). This difference might be due to the presence of an hypoxic fraction in the tumors irradiated in vivo, but not in vitro. Tumor cells from the R3327 tumor variant metastatic to lymph nodes and lungs (R3327-MATLyLu), were irradiated in vitro. The radiation effect was evaluated by in vitro colony formation in agar and by in vivo lung colony assay. The colony formation in agar yielded a D0-value of 1.09 Gy. No radioresistant subpopulation was identified in this variant. A similar radiosensitivity was observed by the in vivo lung colony assay (D0 1.39 Gy). The mean inactivation dose calculated for R3327-AT cells (3.45 Gy) was significantly higher than for the metastatic variant (2.00 Gy).

Radical prostatectomy and adjuvant radioactive gold seed placement: results of treatment at 5 and 10 years for clinical stages A2, B1 and B2 cancer of the prostate

Between 1977 and 1988, 131 patients with adenocarcinoma of the prostate underwent combined radical prostatectomy and intraoperative radioactive gold seed placement. Of these 131 patients 80 were clinically assessed as having stage A2 (12), B1 (43) or B2 (25) cancer and they are the subject of this review. The average dose of radioactivity administered to each patient was 96.6 mCi, and mean followup was 65 months (median 64 months). No patient in this series received any other form of adjuvant therapy until disease recurrence was demonstrated. Local recurrences were observed in 2 patients (2.5%) in this series while distant recurrences were observed in 10 (12.5%). Cancer specific survival free of disease at 5 years was 100% for clinical stage A2, 91% for B1 and 75% for B2 cancers. The 10-year survival free of disease was 100% for clinical stage A2, 82% for B1 and 68% for B2 cancers. Covariants of clinical stage and seminal vesicle involvement influenced survival free of disease in a statistically significant manner (p less than 0.05) while pathological stage and degree of tumor differentiation did not. Mild to severe complications were observed in 12 patients (15%). Intraoperative placement of radioactive gold seeds into unresected pelvic tissues surrounding the site of prostatectomy offers a theoretical advantage in treatment by delivering tumoricidal levels of irradiation to residual foci of cancer not appreciated at the time of surgery. Our results suggest that increases in cancer specific survival free of disease over that previously reported for prostatectomy alone may be achieved through this combined treatment regimen. Furthermore, it is our opinion that therapeutic gains can be achieved without the attendant increases in morbidity and treatment delay often associated with adjuvant external beam radiotherapy.

Pre and posttreatment evaluation of sexual function in patients with adenocarcinoma of the prostate

Twenty-seven patients with adenocarcinoma of the prostate, and available partners, were interviewed to qualitatively and quantitatively assess their level of sexual function prior to and 12 months after radiotherapy. Assessments were made using the Derogatis Interview for Sexual Functioning (DISF). Five domains of sexual functioning are measured: sexual fantasy, arousal, experience, orgasm, and drive. Prior to therapy 17 of 27 patients (62.9%) were considered impotent. There were eight patients with a DISF score of less than 20 who were impotent. Six patients had a DISF score of greater than 47 and were considered potent. Of the patients with DISF scores between 20-47 four were potent, and nine were impotent. Post radiation therapy three of the patients considered potent (with a score greater than 47) maintained their potent status. Four patients considered impotent prior to therapy became potent after therapy. All patients with a score less than 20 prior to radiation therapy remained impotent after therapy. Results indicate that an objective evaluation of sexual function pre treatment is necessary to determine the effect of radiotherapy. Our method of qualitative assessment of sexual function was easy to implement, was reproducible and could be used to evaluate long-term effects of radiotherapy on sexual function. Of the patients presenting for radiotherapy, 62.9% were impotent. Twelve months after radiation therapy 19 of 27 (70.3%) were impotent.

Laser combined with TURP in the treatment of localized prostatic cancer

Laser treatment associated with transurethral resection of the prostate is a new and promising treatment of the stages T0 diffuse, T1 and T2 prostatic cancer. Our standardized treatment procedure gives few complications. So far we have not recorded any local recurrence in the 26 patients we have treated and followed up from 6 to 42 months.

Identification of residual cancer in the prostate following radiation therapy: role of transrectal ultrasound guided biopsy and prostate specific antigen

Transrectal, ultrasound guided needle biopsies were performed in 27 men greater than 18 months (mean 5.2 years) after radiation therapy for prostate cancer. Of the patients 18 (67 per cent) originally had localized (stage A or B), 6 had stage C and 3 had stage D1 prostate cancer. In addition to biopsies directed at any hypoechoic regions of the prostate, multiple systematic biopsies were performed from the apex to the base bilaterally and the seminal vesicles also were biopsied regardless of appearance. Of 27 patients 25 (93 per cent) had post-irradiation biopsies positive for cancer, including 5 of 5 with prostate induration and 20 of 22 (91 per cent) with normal post-irradiation digital rectal examinations. Ultrasound findings per se were poorly correlated with pathological findings in the irradiated prostate. Directed biopsies of hypoechoic areas were positive for cancer in 67 per cent of the cases and isoechoic areas were positive for cancer in 65 per cent. Seminal vesicle biopsies were positive in 7 patients (26 per cent), including 4 with normal post-irradiation rectal examinations and 4 with normal ultrasound appearance. Of 12 patients 10 (83 per cent) with serum prostate specific antigen levels less than 10 ng. per ml. had positive biopsies, as did all 15 with levels greater than 10 ng. per ml.

Radiosensitivity of human prostate cancer and malignant melanoma cell lines

The relative radioresponsiveness of human prostate cancer compared to malignant melanoma is well known. The effects of beta-estradiol or testosterone on the X-irradiation survival of several human cell lines were studied, including: human prostate carcinoma cell lines PC3 and DU145 and human malignant melanoma cell lines A375 and A875. Lines PC3 and DU145 demonstrated 55-61 fmol per 10(6) cells of androgen receptor with no detectable estrogen or progesterone receptor. Cells were irradiated at 120 cGy/min dose rate. There was no detectable toxicity of up to 10(-4) M testosterone or beta-estradiol on PC3 or DU145 cells in the absence of X-irradiation. At plating efficiencies from 11-13%, and plating densities of 1 x 10(4) cells per 60 cm2 flask, cell lines PC3 and DU145 demonstrated a Do of 108.5 +/- 6.5, n 2.1 +/- 0.7 cGy, and Do of 143.5 +/- 1.5 cGy, n 2.4 +/- 0.5, respectively. The addition of testosterone or beta-estradiol at 10(-4) to 10(-10) M prior to or after, X-irradiation did not alter radiosensitivity. At the same dose rate of 120 cGy/min, malignant melanoma cell lines A375 and A875 had a Do of 125 +/- 2.5 cGy, n 1.56 +/- 0.8 SF2 0.65 +/- 0.03 and line A875 demonstrated a Do of 129 +/- 4.5 cGy, n 1.58 +/- 0.4 SF2 0.55 +/- 0.04, respectively. The radiosensitivity of melanoma cell lines did not decrease at low dose rate 5 cGy/min. Thus, the in vitro radiosensitivity of androgen receptor positive prostate cancer cell lines is not necessarily altered by the presence of androgen before or after irradiation. The data support the concept that all malignant melanoma cell lines do not show a broad-shouldered cell survival curve in vitro and intrinsic cellular radioresistance.

Experience in the treatment of localized carcinoma of the prostate by definitive external irradiation

One hundred and sixteen patients with stages A2, B, and C histologically proven adenocarcinoma of the prostate were treated by definitive radiation. They received first whole pelvic irradiation, 46 Gy in 23 treatments, followed by a prostatic "boost" of 20 Gy in 10 fractions. Five-year survival rates varied between 39 and 84%. Prophylactic hormonal manipulation and transurethral resection of the prostate (TURP) did not influence survival figures. Complications of radiotherapy were in an acceptable range. It is concluded that external beam irradiation is an effective, simple, and usually well-tolerated treatment modality for localized carcinoma of the prostate. Stage and degree of differentiation and response of the primary tumour to radiation are predictors of patient outcome. There is no advantage in prophylactic hormonal manipulation, and TURP does not influence survival according to our experience.

Radical radiotherapy in prostatic carcinoma

During the years 1978-1986 111 fairly elderly patients with prostatic carcinoma in clinical stages B, C, or D, and usually having tumours that were poorly differentiated, received radical radiotherapy to the prostate and bladder and to the adjacent lymph node regions. The side effects were comparable to those reported in the literature. During the follow-up 72% of the patients sooner or later (actuarial analysis) developed local recurrence or distant metastases. The projected survival rate at 8 years was 25%, and should be compared with the 65% expected for an age-matched Swedish male population. After 3 years the two survival curves became rather parallel, indicating a 'cure' rate of the order of 49%. There was a significant difference in survival between patients clinically judged to have only intracapsular carcinoma and those considered to have extracapsular carcinoma. The relatively modest survival figures in the present series reflect the malignant nature of poorly differentiated carcinoma of the prostate.

The effect of dose on local control of prostate cancer

Three patterns of care outcome surveys in prostate cancer totalling 1516 patients had been combined and analyzed for the effect of dose on infield recurrence. There are significant dose effects observed in the overall data (1516 patients, p = .003), Stage B cancers (725 patients, p = .004) and Stage C cancers (624 patients, p = .059). No dose effect was observed for Stage A cancers (168 patients, p = .217) within the dose range observed (5500 cGy to greater than 7000 cGy). For patients with Stage B cancer one may conclude that dose between 6000 cGy and 6999 cGy is appropriate. Patients treated to less than 6000 cGy show a highly significant increase in local failure. Patients treated to greater than 7000 cGy do not show a demonstrable improvement in local control, but do show an increase in complications. Patients with Stage C cancer appear to require dose that is equal or greater than 7000 cGy to obtain the best local control, and the potential increased morbidity of these high doses appears to be justified in this stage of the disease. Patients who have been given hormonal therapy more than 1 month prior to radiation therapy show an increase in local failure rate for all stages of cancer. This is presumed to be the selection of poor risk patients for adjuvant hormonal treatment or by referring non-responding hormone treated patients for radiation therapy. Histologic grade exerts a major influence on local failure for patients with Stage C disease (p = less than .001), identifying an important stratification point for prospective clinical trials and a sub-group for which it is important to develop strategies for improving local control. The policy of treating all stages of prostate cancer with the same dose is not supported by these data.

Combination therapy with flutamide and [D-Trp6]LHRH ethylamide for stage C prostatic carcinoma

Sixty-seven previously untreated patients presenting with clinical stage C prostatic carcinoma with no evidence of distant metastases received combination therapy using the antiandrogen Flutamide and the LHRH agonist [D-Trp6]LHRH ethylamide for an average duration of treatment of 23.5 months. Only five patients have so far shown treatment failure with 91.8% of the patients still in remission at 2 years. Three patients have died from prostate cancer while three have died from other causes, 93.5% of the patients being alive at 2 years. Local control was achieved rapidly in all except one patient. Urinary obstruction and hydronephrosis were corrected in all cases. When comparing to recent data obtained after single endocrine therapy (orchiectomy or estrogens), or radiotherapy, the rate of treatment failure at 2 years is 3.5-fold lower after combination therapy (8.2%) than monotherapy (28.4%). The death rate at 2 years following start of the combination therapy is 6.5% while it is on average 22.2% (3.4-fold higher) in the studies using monotherapy (orchiectomy or estrogens) or radiotherapy. The present data suggest that treatment of prostate cancer with combination therapy before clinical evidence of dissemination of the disease permits a better response which is possibly explained, at least in part, by the lower degree of dedifferentiation and heterogeneity of the tumors.

Effect of local tumor control on distant metastasis and survival in prostatic adenocarcinoma

Of 495 patients definitively irradiated for prostatic carcinoma, 286 with a minimum follow-up of thirty-six months were studied. While tumor histology appeared to predict prognosis, the poorly differentiated tumors showing the highest incidence of distant metastasis and the lowest survival, local tumor control was an important factor within the poorly differentiated group. Of those with local recurrence, distant metastases developed in 68 per cent compared with 37 per cent of those with no local disease (p = 0.025). Survival was similarly affected with 86 per cent of those with locally controlled tumor who were alive at five years (not significantly different from the more well-differentiated tumors) versus a 56 per cent actuarial survival in those with locally recurrent disease (p less than 0.05).

Percutaneous transperineal placement of gold 198 seeds for treatment of carcinoma of the prostate

Thirty-one patients have been treated for carcinoma of the prostate with 198Au seeds placed transperineally using transrectal ultrasonic guidance. Twenty patients have been followed postoperatively for periods ranging from 3 to 31 months, with an average follow-up time of 12 months. Cumulative dose of radiation to the prostate calculated by dosimetry was either 9,000 rads or 15,000 rads. Serial transrectal ultrasound examinations performed on these patients showed a decrease in prostate size in all patients within 6 months of treatment, with a statistically significant decrease observed between the third and sixth months. No significant difference in amount or rate of tumor regression was noted when tumor stage and grade were correlated to volume decrease after treatment. Patients who received the larger doses of radiation (15,000 rads) showed a significantly greater rate of decline in prostatic volume than those who received 9,000 rads. Seven patients underwent prostate biopsy between 12 and 18 months after treatment; six biopsies showed residual tumor. Complications after treatment included urinary retention because of prostatic edema (three), radiation urethritis (three), and rectal ulceration (one). Transperineal placement of 198Au is well tolerated and offers an alternative to external beam radiation for treatment of carcinoma of the prostate.

Radical treatment of prostatic carcinoma by megavoltage X-ray therapy

The case records of 116 patients treated with radical megavoltage X-ray therapy for carcinoma of the prostate have been reviewed. The age-corrected actuarial 5-year survival rate was 60.0% and the 10-year rate was 31.5%. Multivariate analysis demonstrated that T classification was the strongest prognostic variable but a long delay between diagnosis and radiotherapy also had a detrimental effect on prognosis. The incidence of severe acute and late radiation morbidity was low. Radical radiotherapy has been shown to be a safe and effective form of management for localised carcinoma of the prostate.

First clinical experiences on neodymium-YAG laser irradiation of localized prostatic cancer

This first clinical report on Neodymium-YAG laser irradiation of localized prostatic cancer presents our experiences in 63 patients during 4 years. Transurethral resection extending to the capsule and subsequent laser irradiation according to our standardized treatment procedure give few complications and good functional results. Actuarial disease-free survival is 98% on one year and 80% in the 2-4 year period. The results are promising and comparable to short-term results obtained by radiotherapy and/or interstitial radioactive implants. Further experience is necessary for a definitive comparison to established treatment modalities.

Comparison of whole pelvis versus small-field radiation therapy for carcinoma of prostate

One hundred thirty-six patients with adenocarcinoma of the prostate gland Stage A2 (12 patients), Stages B1 and B2 (26), Stage C (64), and Stages D1 and D2 (34 patients) were evaluated clinically and treated in a similar fashion at three hospitals. Megavoltage radiation therapy units were employed to deliver 4,600-5,000 cGy to the whole pelvis, and the prostatic area was treated for an additional 2,000 cGy (boost). Local recurrence was infrequent (8/136 = 6%), and the five-year actuarial survival and disease-free survival rates were 85 and 42 per cent, respectively. Adverse clinical parameters included poor histologic differentiation, age younger than sixty years, and diagnosis by transurethral resection of the prostate rather than needle biopsy in Stage C patients. Severe acute reactions occurred in only 2 patients, and only 2 patients were hospitalized for severe chronic (late) reactions. Whole pelvis radiation yielded a statistically significant improved five-year survival and three-year disease-free survival for similarly evaluated patients for Stage C but not for Stages A and B when compared with 116 patients treated with small-volume radiation (prostate area), previously reported from these three hospitals.

Intraoperative radiotherapy in the definitive treatment of localized carcinoma of the prostate

A preliminary analysis of the effectiveness of intraoperative radiotherapy with an electron beam for the treatment of prostatic cancer in 14 patients is presented. The perineal approach was employed as an operative procedure for placing a treatment cone onto the tumor. The electron energy used for irradiation ranged from 10 to 14 MeV. Of five patients treated by intraoperative radiotherapy alone, four who received single doses of 3000 to 3500 cGy achieved local control. One of these patients, however, who received 3000 cGy, had a local recurrence occurred at the sixth year after the treatment. A patient treated with 2800 cGy failed. A single dose of 2000 or 2500 cGy was delivered intraoperatively to nine patients as a boost dose in conjunction with external irradiation of 5000 cGy for the treatment of pelvic lymph nodes. All nine patients achieved local control. None of the 14 patients developed any serious complication of the bladder, urethra or rectum, which has been associated with intraoperative electron irradiation. Although no definite conclusion can be drawn at present because of the small number of patients and insufficient follow-up, the results suggest that single doses of 3300 cGy by intraoperative radiotherapy alone or 2500 cGy as a boost in conjunction with external radiotherapy can be curative for prostatic cancer with minimal morbidity.

Radical prostatectomy in the management of localised carcinoma of the prostate

During the years 1971 to 1983 24 patients underwent radical prostatectomy for localised carcinoma of the prostate. There was one post-operative death from a pulmonary embolism, but all other patients were available for follow-up. All tumours were confirmed on palpation to be clinically localised to the prostate. Patients with clinical stages T0, T1, and T2 were referred for radical surgery. Patients with incidental carcinoma (T0), with less than 10% of the total tissue involved with carcinoma, were not subjected to surgery, and were followed up by observation only. Two patients developed recurrence of tumour at 18 to 12 months, and 2 years. One patient died 1 year later from the disease; he had a pathological T3 tumour with microscopic extension into the seminal vesicles. All other patients are alive and tumour-free at follow-up and 20 of the 23 patients are fully continent.

Carcinoma of the prostate treated by pelvic node dissection, iodine-125 seed implant and external irradiation: a study of rectal complications

The University of Missouri-Columbia protocol for localised cancer of the prostate calls for pelvic node dissection, 10000 cGy at the periphery of the prostate from 125I and 4000 cGy in 20 fractions to the whole pelvis using supervoltage X-ray therapy. Rectal complications were studied in 104 patients; acute and chronic reactions were defined. During external irradiation 54% did not develop diarrhoea, 43% had mild diarrhoea and 3% had severe diarrhoea. In the chronic stage 77% did not have diarrhoea, 12% had delayed, non-distressing rectal bleeding which did not need specific treatment or needed only simple treatment, 7% had prolonged distressing proctitis and 4% had rectal ulceration or recto-urethral fistula necessitating colostomy. Each of the four patients who had colostomy had an additional aetiological factor (arterial disease, pelvic inflammation, additional radiation, pelvic malignancy or second operation). None of the patients entered in the combined brachytherapy and teletherapy programme, and in whom 0.5 cm space was maintained between the closest seed and the rectal mucosa, developed prolonged proctitis.

Improved control of bulky prostate carcinoma with sequential estrogen and radiation therapy

Patients with bulky prostate cancer have usually been treated by palliative measures because the likelihood of tumor control with definitive irradiation has been low and the development of distant metastases high. The addition of estrogen to irradiation has not been shown to be of value. However, we believe the method of estrogen administration may have been the cause for the apparent lack of benefit. Estrogen had been started either concurrent with irradiation or had been used for palliation and was given for long and unscheduled time periods prior to irradiation. We have used estrogen for two months prior to and concurrent with irradiation. We postulated that in those patients with estrogen responsive cancer, the reduced tumor burden prior to irradiation could enhance tumor control and survival. Between 1975 and 1980, 25 patients with bulky prostate cancer received sequential estrogen and irradiation, 12 patients irradiation alone and six patients irradiation after having become refractory to long-term estrogen use. One patient was lost to follow-up. Eighteen of 25 (72%) treated by sequential estrogen and irradiation, 14/17 (82%) with estrogen responsive cancer and 4/8 (50%) with estrogen resistant cancer had a complete tumor response. Six of 11 (55%) patients treated by irradiation alone and 2/6 (33%) treated by irradiation for estrogen refractory cancer had a complete tumor response. Disease-free survival was observed in 13/25 (52%) treated by sequential estrogen and irradiation, and 8/17 patients (47%) with irradiation. It is also possible the improved survival in the estrogen responsive group was a direct result of improved local control. Persistent local disease can act as a source for distant metastases. Distant metastases was observed in 15% of patients when the primary tumor was controlled and 30% when there was persistent or recurrent local disease. Also, progressive local disease can be an important cause of death. This was most evident in our patients with estrogen refractory cancer. Almost all patients in this group had progressive local disease that caused serious urinary bleeding and urinary infection that were considered the major cause of death. Our results suggest bulky prostate cancer should be aggressively treated when first diagnosed. The value of adjunct estrogen is unproven. Our results with the use of estrogen prior to and concurrent with irradiation is encouraging. Estrogen may shrink the cancer and allow for a more favorable geometry for external irradiation. Tumor control and survival may be thereby improved.(ABSTRACT TRUNCATED AT 400 WORDS)

Severe rectal injury following radiation for prostatic cancer

Between 1970 and 1981, 348 patients underwent definitive irradiation. Of these patients 6 (1.7 per cent) sustained severe rectal injury as manifest by major rectal bleeding, rectal stricture, rectal mucosal slough and rectal ulceration. Severe rectal injury was observed in 0 of 13 patients (0 per cent) treated with 125iodine, 3 of 329 (1 per cent) treated with 6,400 to 6,800 rad external irradiation, 2 of 39 (5 per cent) treated with 7,000 to 7,300 rad external irradiation, and 1 of 7 (14 per cent) treated with 198gold and external irradiation. The impact of radiation dose, radiation therapy technique and surgical trauma was assessed. Rectal injury was managed by supportive measures in 2 patients and by diverting colostomy in 3 with benefit. One patient underwent abdominoperineal resection. A small bowel fistula and an intra-abdominal abscess developed, and the patient died.

Adriamycin and cyclophosphamide versus hydroxyurea in advanced prostatic cancer. A randomized Southwest Oncology Group study

Over a 24-month period, the Southwest Oncology Group (SWOG) conducted a randomized prospective chemotherapeutic trial in 158 patients with advanced prostatic cancer. Patients were initially randomized to receive either a combination of Adriamycin and cyclophosphamide (AC) or a single agent, hydroxyurea (H), and then crossed over to the other treatment on failure. Of the 137 evaluable patients, 43 (31%) had classically measurable metastatic disease in the lymph nodes, skin, chest, or liver. Focusing their efforts on this subset of patients with measurable disease, the authors of this report found the combination AC to have a superior response rate to the single agent, hydroxyurea. Objective response to AC was seen in 6 of 19 (32%) and in only one of 24 (4%) patients randomized to hydroxyurea (P = 0.06, Fisher's exact test). However, in the larger group of 137 evaluable patients, a survival advantage was not seen for those individuals treated with AC. Failure to demonstrate a survival advantage for an objectively superior drug combination would suggest the need for more active phase II agents in this disease.

Percutaneous lymph node aspiration biopsy and tumor grade in staging of prostatic carcinoma

Percutaneous fluoroscopy-guided fine-needle aspiration biopsy was performed for staging procedures in 31 patients with clinically localized carcinoma of the prostate and showed overall accuracy of 93.54%, with a false-negative rate of 6.46%. The Gleason grading system was found to be highly accurate in predicting the absence or presence of nodal metastases in low- and high-grade tumors (Gleason's sums 2, 3, or 4, and 8, 9, or 10). The combination of pelvic node biopsy aspiration and tumor grade can result in a very accurate prediction of nodal involvement, and may spare patients a staging lymphadenectomy or even an unnecessary radical operation.

Effects of external radiation therapy for cancer of the prostate on the serum concentrations of testosterone, follicle-stimulating hormone, luteinizing hormone and prolactin

Testosterone, luteinizing hormone, follicle-stimulating hormone and prolactin were analyzed in serum from 31 patients with carcinoma of the prostate treated primarily with megavoltage radiation therapy. The total tumor dose varied between 58 and 71 gray (mean 63.5 gray). Absorbed doses to the testes were measured at approximately 1 to more than 10 gray. We investigated retrospectively 17 patients 3 to 60 months (mean 20 months) after therapy and found significantly lower serum testosterone concentrations and significantly higher luteinizing and follicle-stimulating hormone concentrations than in age-matched controls. Of the patients 14 were followed before and after radiation treatment. Testosterone concentrations were reduced significantly 1 week as well as 3 months after treatment but pre-treatment values were found on analysis 6 and 12 months after treatment. The values for luteinizing and follicle-stimulating hormones were significantly higher 3, 6 and 12 months after radiation treatment compared to pre-treatment values. The follicle-stimulating hormone value already increased after 1 week. The greatest observed testosterone alteration occurred 1 week after treatment in patients who received more than 10 gray over the gonads. The use of lead shields protecting the testes reduced the dose absorbed to the gonads by approximately 50 per cent.

Acute side effects and late complications after radiotherapy of localized carcinoma of the prostate

In the last two decades, many authors have treated prostatic carcinoma by radiation therapy. Accumulated data have been updated, after 10 and 15 years of follow-up. In stage A and B, the reported survival and local control rates after irradiation (20, 22, 30, 34, 35, 39, 42) are as good as in selected patients treated by radical prostatectomy (9, 18, 23). In stage C, the results after irradiation (20, 22, 30, 42) are better than after radical surgery (23, 43). However, patients are nonrandomly selected and the methods of statistical analysis differ. Therefore, a valid comparison cannot be made. The therapeutic ratio is determined by survival and local control, and also by therapy related complications. It is therefore of interest to find out from radiotherapy series if their incidence is related to the treatment technique. Unfortunately, relatively few studies accurately describe treatment technique and complications. Gastro-intestinal radiation injury becomes significant when the dose at the posterior rectal wall is 65-76 Gy and the length of the treated rectum is at least 10 cm. A hot spot of 80-84 Gy needs to be only 2 to 3 cm to increase the risk of late bowel stenosis. Genito-urinary complications are influenced by local extension of the tumor and by previous surgical manipulations. A dose at the prostatic area exceeding 70 Gy should be avoided, as it does not improve local control (22, 35) and apparently increases the risk of late urethral stricture and penile/scrotal edema (12, 39). The dose at the anterior bladder wall correlates with other types of genito-urinary complications. Therefore, the anterior bladder wall should not receive a dose higher than 65 Gy. Incidence of impaired potency after irradiation is usually 30 to 40%, which is much less than after radical surgery. As many data in the literature dealing with radiation treatment of the prostate are still inadequate a more standardized reporting is recommended to make comparison of effectiveness and side effects possible.

Prognostic significance of tumor grade and stage in the patient with carcinoma of the prostate

Available English language articles relating the grade, stage, and grade-stage of carcinoma of the prostate to evidence of tumor progression and survival in untreated and treated patients have been reviewed. Observations of the extremes of the spectrum of biological behavior of carcinoma of the prostate have been emphasized; for example, tumor progression, never or always; survival, never or always. The reported experiences indicated the following; namely, 1) reproducible biologically meaningful grading is achievable; however, grade cannot be utilized as a reliable indicator of stage; 2) accurate staging provides information that correlates with tumor progression and survival in groups of patients. However, unexpectedly prolonged or abbreviated progression-free survivals occur frequently enough in every stage, except perhaps patients with clinically unsuspected focal carcinoma, to indicate that the natural history and treatment response of individuals grouped by stage is far from homogeneous; 3) appropriate use of carefully obtained grade and stage information together maximizes the accuracy of prognostic attempts and is necessary to evaluate treatment results. At the present time, assessment and consideration of the grade and stage of carcinoma of the prostate is essential to formulate prognosis and advise and evaluate treatment in patients with this disease.

Combined external radiotherapy and hormonal therapy for localized carcinoma of the prostate

Forty-nine patients with localized carcinoma of the prostate were treated by external radiotherapy together with hormonal manipulation and were followed up to six years. Hormonal manipulation included bilateral orchiectomy and diethylstilbestrol, 3 mg/day. The cumulative five-year survival for the 49 patients was 87.6%, with 11% progression rate to stage D during that period. In 40 patients (81.6%), a decrease in the size of the prostate was noted. In none of the patients was there local recurrence of the tumor during the period of follow-up. Transient gastrointestinal and/or urinary symptoms occurred following radiotherapy in 11 patients (22.4%), and in four patients severe cystitis or proctitis appeared. Complications related to hormonal therapy occurred in 11 patients (22.4%). The high survival rates reported herein, together with the low progression rate to stage D during six years of follow-up, may justify the early institution of radiotherapy in combination with hormonal manipulation for patients with localized carcinoma of the prostate. A randomized study with an extended number of patients is underway to further evaluate this mode of therapy.

The tolerance to multiple daily fractionated radiotherapy for the treatment of prostatic and bladder carcinoma: a feasibility study

A modified fractionation schedule was designed with the purpose of reducing the treatment burden. Three fractions of 2 Gy with four hours interval were given during 5 days. The whole scheme was repeated after a rest period of 4 weeks. This makes it possible to deliver a dose of 60 Gy in 10 treatment days and over a total time of 6 weeks. A total of 30 patients, 22 with prostatic cancer and 8 with invasive bladder carcinoma, have been treated. The feasibility has been found to be very good. Forty-seven percent of the patients had acute morbidity, although it was mild in all patients. One patient had a persistent, another had a transient delayed symptom, and one had a severe late complication. The tolerance to this schedule is better than that observed with conventional fractionation schedules. Together with the drastic reduction of the total treatment days, this multiple daily fractionation (MDF) schedule has already been shown to improve the therapeutic ratio by diminishing the burden on the patients. Longer follow-up necessary for the assessment of the efficacy of this schedule for local tumor control. However, with a follow-up period of 7 to 16 months no recurrence of the prostate cancer in the pelvis has been observed. These results warrant further exploration of the possible benefits of modifications in time-dose-fractionation schedules.

Radiotherapy for prostatic carcinoma: post-irradiation prostatic biopsy and recurrence patterns with long-term followup

From 1968 through 1975, 159 patients with stages A, B and C adenocarcinoma of the prostate were treated with supervoltage radiation therapy. A median dose of 7,200 rad was given. The influence upon survival of grade, stage and a positive biopsy result after irradiation is analyzed. Over-all survival is a patently imprecise test of local treatment because patients die of intercurrent disease and are alive with metastases for significant intervals. The classification of survival with no evidence of recurrent disease excluded those patients dying of intercurrent disease. Therefore, the rate of survival free of disease always will be greater than the over-all survival rate in these patients, and a certain percentage of the patients without evidence of cancer will harbor subclinical disease. The 5 and 10-year survival rates free of disease were 80 and 69 per cent, respectively, in 51 patients with stages A and B cancer, and 66 and 47 per cent, respectively, in 108 with stage C disease. The 5 and 10-year over-all survival rates were 72 and 56 per cent, respectively, in the former and 68 and 39 per cent, respectively, in the latter patients. Survival free of disease and death of prostatic carcinoma were influenced adversely by advancing grade and stage (p less than 0.05), while over-all survival was influenced adversely by grade (p equals 0.02) but not by stage (p greater than 0.05). A positive biopsy result after irradiation did not predict survival free of disease, over-all survival or death of prostatic cancer in patients followed for 10 years (p greater than 0.05).