Adjuvant estrogen following radiation therapy for stage C adenocarcinoma of the prostate: long-term results of a prospective randomized study

Prostate cancer--the impact of irradiation on urinary outlet obstruction

A series of 245 patients with prostate cancer treated by external irradiation was analysed to assess the impact of irradiation on urinary outlet obstruction. Prior to irradiation, obstruction was observed in 147/245 patients (60%). Irradiation either with or without hormonal therapy was as efficacious as transurethral resection of the prostate (TURP) in alleviating obstructive symptoms; 14/16 patients treated by irradiation alone responded, as did 19/19 who received hormonal therapy and irradiation and 109/112 who underwent TURP and irradiation. Following irradiation, 41/245 patients developed post-irradiation obstruction, 26/213 had post-irradiation strictures and 15/32 developed recurrent cancer. Surgical intervention was required less often for the management of recurrent obstruction caused by stricture as compared with recurrent cancer. TURP and urinary outlet obstruction acted as independent and additive variables to the development of post-irradiation stricture. Thus the avoidance of TURP in patients with obstructive symptoms reduced but did not eliminate the risk of developing a stricture.

Prostate-specific antigen as a prognostic factor for prostate cancer treated by external beam radiotherapy

The potential prognostic significance of prostate-specific antigen (PSA) serum concentrations was evaluated in 171 patients with stages A2 to C adenocarcinoma of the prostate treated with external beam radiotherapy. After a median follow-up of 17 months, 12 patients sustained relapse of disease and PSA levels were found to be prognostically significant in three ways. (a) Pretreatment PSA level: none of 59 patients with a pretreatment PSA level less than or equal to 4 ng/ml relapsed to date and only one developed a subsequently rising PSA profile; 7 of 102 patients (7%) with a pretreatment PSA level in the range 4-40 ng/ml relapsed and 17 (17%) showed a rising PSA profile; 5 of 10 patients (50%) with a pretreatment PSA level greater than or equal to 40 ng/ml relapsed and six (60%) developed rising PSA values. The differences were significant and were maintained when patients were stratified by stage or grade. (b) PSA level at 6 months: for patients with pretreatment PSA levels in the range 4-40 ng/ml, a 6-month value greater than 2 ng/ml predicted a significantly worse outcome than a 6-month value less than 2 ng/ml. (c) Rising post-treatment PSA values: following a radiation-related nadir in PSA levels, 24 patients experienced rising PSA values and 8 (33%) relapsed at a median time of 5 months after onset of the rising values--a significantly higher relapse rate than observed in patients with non-rising PSA values. Whether the majority, or all, of the patients with rising PSA levels relapse, requires further follow-up. In conclusion, serum PSA levels are strong prognostic determinants of outcome following radiotherapy for prostate cancer and appear to add prognostic information independently of tumor stage and grade.

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.

Biopsy after external beam radiation therapy for adenocarcinoma of the prostate: correlation with original histological grade and current prostate specific antigen levels

We obtained post-irradiation biopsies in 37 men with initially stage T3 prostatic adenocarcinoma treated by external beam radiotherapy. Eligibility for post-irradiation biopsy included no clinical local failure, interval since treatment of 24 months or more and no endocrine therapy. Of the 37 patients 23 (62%) had negative biopsies while 14 (38%) had positive biopsies. Of 23 patients whose original cancer was well or moderately differentiated 18 (78%) had negative biopsies, compared to only 5 of 14 (36%) of those with poorly differentiated cancer (p less than 0.03). Among 19 patients whose current serum prostate specific antigen (PSA) value is less than 2.5 ng./ml. 15 (79%) had negative biopsies, compared to only 4 of 14 (29%) with a PSA level of greater than 2.5 ng./ml. (p less than 0.02). These results strongly suggest that there is a low probability of positive post-irradiation biopsy regardless of its significance in men with a normal prostate by palpation and a normal serum PSA value. However, short followup since biopsy precludes analysis of the predictive value of post-irradiation biopsy on long-term local and distant disease status.

Natural course of clinically localized prostate adenocarcinoma in men less than 70 years old

A total of 61 patients, less than 70 years old at diagnosis, with clinical stage T1-2, NX, M0, cytologically well or moderately differentiated prostate adenocarcinoma was prospectively included in a surveillance study. Median patient age was 63 years (range 38 to 69 years). Mean followup was 96 +/- 24 months. The probability of local progression to stage T3 disease after 5 and 10 years was 49 and 72%, respectively. The probability of metastases developing after 5 and 10 years was 8 and 23%, respectively. The probability of dying of prostate adenocarcinoma was 2 and 8%, respectively. Moderately differentiated cancer progressed locally significantly faster than well differentiated disease. The relative number of patients who had metastases or died of prostate adenocarcinoma found in our study was comparable to the relative numbers reported after radical prostatectomy and radiation therapy. Therefore, deferred therapy may be an alternative to active therapy in patients with clinically localized prostate adenocarcinoma and with a life expectancy of less than 10 years.

The role of serum prostatic acid phosphatase in the management of adenocarcinoma of the prostate with radiotherapy

Between 1974 and 1983, 472 patients with clinically-staged adenocarcinoma of the prostate treated by radiotherapy had baseline and follow-up prostatic acid phosphatase (SPAP) measurements by the enzymatic Roy method. The mean pretreatment SPAP was higher in Stage C (0.65 mIU/ml) than in combined Stages A2/B (0.43 mIU/ml), (p less than 0.05). Likewise, the incidence of elevated SPAP (greater than 0.8 mIU/ml) was also higher in Stage C (12%) than in Stages A2/B (3%), (p less than 0.01). Only 3 of 113 patients in Stages A2/B had an elevated SPAP and all three remain disease-free. In Stage C elevated SPAP was an adverse prognostic factor, and patients with a normal SPAP fared worse if their value was in the upper half of normal (greater than 0.4 mIU/ml) rather than in the lower half (less than or equal to 0.4 mIU/ml). However, in Stage C, tumor grade was found to correlate with initial SPAP, so that the higher the grade, the higher was the mean SPAP and the greater was the incidence of elevated SPAP. When stratified for grade, the prognostic significance of low-normal versus high-normal SPAP in Stage C was lost. An elevated SPAP was, however, an independent adverse prognostic factor for patients with intermediate and high grade tumors. Following radiotherapy, mean SPAP values fell significantly within 1-3 months. For patients with initially normal SPAP, this fall was of no prognostic significance. In 80% of the patients with baseline elevation of SPAP, the values normalized following treatment and the relapse rate in these patients was 51%, which was still higher than the relapse rate of patients with initially normal SPAP (33%) (p less than 0.05) but was lower than the 89% relapse rate in patients whose postradiation SPAP did not normalize (p less than 0.05). Pretreatment SPAP was of independent prognostic significance for only 6% of the study population and therefore has quite limited usefulness in the management of this disease. SPAP decreases following radiotherapy, but this is of prognostic significance only for the small group of patients with elevated pretreatment values.

Prostate cancer: post-irradiation incontinence

The experience of 272 patients with prostate cancer treated between 1976 and 1987 by external irradiation was reviewed to assess causal factors for post-irradiation incontinence and to determine measures to reduce the risk of this complication. No patient had incontinence before definitive irradiation or radical prostatectomy. Post-irradiation incontinence was observed in 19 of 272 patients (7%), including 14 with mild, 2 with moderate and 3 with severe disease. Incontinence after definitive irradiation was not significantly related to tumor stage or tumor control: 8 of 192 patients (4%) had local control and 2 of 33 (6%) had local failure. Incontinence was related to a urological operation performed in 1 of 105 patients (1%) who underwent needle biopsy and 7 of 130 (5.5%) who underwent transurethral prostatectomy before irradiation. Incontinence was more frequent, 2 of 6 patients (33%), and more severe in patients who underwent transurethral prostatectomy after irradiation. Of 31 patients 9 (29%) were incontinent after radical prostatectomy. No additional patient had incontinence after postoperative irradiation. However, 3 patients had a temporary increase in the severity of incontinence. The risk of post-irradiation incontinence may be decreased by more selective use of transurethral prostatectomy. Of 136 patients 26 (20%) underwent transurethral prostatectomy for tissue diagnosis. A needle biopsy would be the procedure of choice. A total of 29 patients with urinary outlet obstruction was treated without transurethral prostatectomy before irradiation. Ten patients with relatively mild urinary outlet obstruction were treated by irradiation alone, while 19 with more severe urinary outlet obstruction had endocrine therapy before irradiation and none of the 29 patients (0%) had post-irradiation incontinence.

External beam radiotherapy for carcinoma of the prostate

Five hundred nineteen patients with prostate cancer were seen in the Radiation Oncology Division of the State University of New York (SUNY) Health Science Center, Syracuse, New York, between 1969 and 1981. The results for the 239 patients treated with radical intent are reported here. All patients received 60 to 70 Gy to the prostate with megavoltage beam irradiation; 142 with a small field (10 X 10 cm) 360 degrees rotational technique for Stage A, B, or C disease and 69 with a four-field pelvic brick technique (followed by a boost to the prostate) for Stage A through C and D1 disease. Twenty-eight patients were treated postoperatively for residual disease after radical prostatectomy or for recurrent tumor. The minimum follow-up time was 5 years. Actuarial 5-year and 7-year survival rates for Stage A (n = 34), B (n = 100), C (n = 63), and D1 (n = 14) were 91% and 76%, 86% and 75%, 67% and 40%, and 46% and 36%, respectively. The corresponding 5-year and 7-year relapse-free survival rates were 72% and 65%, 77% and 60%, 46% and 28%, and 38% and 25%. The local tumor control rates at 5 years were 91%, 85%, 77%, and 62% for Stage A, B, C, and D1, respectively. In our experience, there was no significant difference in relapse-free survival rates for patients who underwent transurethral resection (TURP) versus those who did not (67% versus 78% for Stage B [P greater than 0.25] and 38% versus 47% for Stage C [P greater than 0.25], respectively). Also there was no significant difference in relapse-free survival rates between large and small field techniques (64% versus 77% for Stage B [P greater than 0.25] and 56% versus 41% for Stage C [P greater than 0.25], respectively). The 5-year and 7-year actuarial survival rates were 90% and 71%, respectively, for the 15 patients with residual tumor and 58% and 33%, respectively, for the 13 patients treated for postprostatectomy recurrence. Severe complications were documented in only nine patients (3.7%) and mild to moderate complications in 53 patients (22%). Larger fields did not cause a higher rate of complications, although small fields were tolerated better than large fields; the significant acute reaction rate was 27% for large field techniques versus 11% for small field techniques (P greater than 0.01). These results confirm that external beam irradiation is an effective treatment for prostate cancer.

Treatment of locally advanced prostate cancer with radiation therapy

External beam radiation has been the most common curative treatment for the patient with Stage C prostate cancer, with ten-year survivals of 38-40 percent and ten-year free-from-recurrence rates of 28 percent and 30 percent. A number of problems are apparent, including the need to confirm positive imaging studies by biopsy, the need to avoid the apparent adverse effects of transurethral resection of the prostate (TURP) in a subset of Stage C patients, the need to complete ongoing prospective trials of adjuvant androgen deprivation, and the need to complete trials of neutron therapy and implants designed to improve local control. Patients with Stage C cancer should be encouraged by their physicians to enter prospective trials addressing these pertinent questions.