Evaluation of serum prostate-specific antigen levels after postoperative radiation therapy for pathologic stage T3, N0 prostate cancer

Influential factors in the response to salvage radiotherapy after radical prostatectomy

OBJECTIVE

To analyze the influential factors in the response in prostatectomized patients with subsequent biochemical relapse (BCR) and treated with salvage radiotherapy (RTP).

MATERIAL AND METHODS

We analyzed 313 patients with pT2/pT3 prostate cancer who were receiving salvage therapy due to biochemical relapse (from a series of 1,310 radical prostatectomies between 1989-2012). Of the 313 patients; 159 (50.8%) only received androgen deprivation (AD), 63 (20.1%) Radiotherapy (RTP) plus concomitant AD and 91 (29.1%) only RTP. Of these, 57 (62.6%) have maintained complete response and 34 (37.4%) had failure response with post-RTP BCR.

RESULTS

Study of the group treated exclusively with salvage RTP. Ninety-one patients were treated with salvage RTP. Median follow-up was 6.4 years and median to recurrence 11 months. Post-RTP biochemical relapse-free survival (PRBRFS) was 68 ± 7% and 30 ± 10% in 5 to 10 years. Median PRBRFS was 7.3 years (6.3-8.3). Initial PSA (HR: 1.08; 95% CI: 1.01-1.1 P=.02) with best PSA cut-off point PSA>20 ng/ml (HR: 13.6; 95% CI: 2.1-86 P=.005) and PSA pre-RTP (HR: 1.9; 95% CI: 1.2-3.3; P=.009), best PSA cut-off point PSA preRTP 0.92 ng/ml (HR: 4.5; 95% CI: 1.3-15.6; P=.01) showed independent influence in the response in the multivariate study. PRBRFS at 5 years, 81 ± 9% versus 58 ± 9% with initial PSA <20 or >20 ng/ml (P=.03). PRBRFS at 5 years, 93 ± 5% versus 53 ± 10% according to PSA pre-RTP <0.9 or >0.9 ng/ml (P=.02).

CONCLUSIONS

In patients treated with salvage RTP after radical prostatectomy, the preoperative PSA>20 ng/ml and PSA preRTP>0.92 ng/ml shows an independent influence on the response.

Salvage radiotherapy for palpable, locally recurrent prostate cancer after radical prostatectomy

PURPOSE

A retrospective study to evaluate the outcome of salvage radiotherapy (RT) for clinically apparent, palpable prostate cancer recurrence after radical prostatectomy (RP).

METHODS AND MATERIALS

Forty-two patients underwent RT for clinically apparent recurrent prostate cancer after RP between 1993 and 1999. The end points and treatment variables of biochemical disease-free survival were evaluated statistically.

RESULTS

The median follow-up was 4.3 years. All 42 patients experienced resolution of clinically detectable recurrence within 1 year after RT. The 5-year biochemical disease-free survival, local control, freedom from distant metastases, and overall survival rate was 27%, 94%, 82%, and 78%, respectively. The initial pathologic stage (T3 or T4; p = 0.04) and interval (<2 years from RP to RT; p = 0.01) were independent predictors of biochemical failure, and RT simulation without contrast (p = 0.05) was nearly significant on multivariate analysis. Three patients (7%) experienced chronic Grade 3 or 4 RT-related toxicity.

CONCLUSION

Salvage prostate bed RT for clinically apparent locally recurrent prostate cancer after RP provides effective local tumor control with modest durable biochemical control. Patients irradiated with a better simulation technique were found to have a more favorable outcome. A consensus on a definition of biochemical disease-free survival after salvage RT is critical for meaningful comparison of the available data and to future progress in treating this disease process.

Biochemical disease-free survival following adjuvant and salvage irradiation after radical prostatectomy

PURPOSE

To present the biochemical cure rates (biochemically no evidence of disease) after external irradiation (RT) in patients with high-risk prostate cancer after radical prostatectomy.

METHODS AND MATERIALS

Seventy-six patients who underwent radical prostatectomy and subsequent RT were included in this analysis. No patient received hormonal therapy. Adjuvant RT was administered in 35 patients (46%), and 41 patients (54%) underwent salvage RT. After prostatectomy, the Gleason score was <7 in 87%, and 24% had seminal vesicle invasion. The median RT dose in the adjuvant RT and salvage RT groups was 60 Gy and 65 Gy, respectively. The biochemical cure rate was defined as a serum prostate-specific antigen of < or =0.2 ng/mL.

RESULTS

The overall 5-year Kaplan-Meier biochemical control rate from the end of RT was 70%. The 5-year biochemical cure rate for adjuvant RT was significantly superior to that after salvage RT (86% vs. 57%). The significant predictors of biochemical failure were seminal vesicle invasion in the adjuvant RT group and the presence of Gleason grade 4 or 5 in the salvage RT group. The clinical local control rate in the prostate bed was 100%.

CONCLUSION

This report demonstrates the efficacy of RT in achieving high biochemical cure rates after radical prostatectomy. Additional clinical studies are required to determine the optimal treatment of patients at high risk of biochemical failure after postprostatectomy RT.

Update on impact of moderate dose of adjuvant radiation on urinary continence and sexual potency in prostate cancer patients treated with nerve-sparing prostatectomy

OBJECTIVES

Adjuvant radiotherapy to the prostatic bed at moderate doses of 45 to 54 Gy achieves results comparable to higher doses. We studied the effect of moderate doses of postoperative radiation therapy on urinary continence and sexual potency in prostate cancer patients who had undergone nerve-sparing prostatectomy.

METHODS

Between November 1983 and December 1992, 255 prostate cancer patients were selected to undergo nerve-sparing prostatectomy. A total of 94 (37%) patients had received adjuvant postoperative radiotherapy, 45 to 54 Gy to the prostatic bed, based on microscopic positive margins, seminal vesicle involvement, and/or Gleason score. Subjective patient reports regarding the potency and urinary continence status were recorded during a semistructured telephone interview at 3 or more years after treatment. The findings in irradiated and nonirradiated patients were compared and correlated to those obtained from the same patients preoperatively and 1 year postoperatively.

RESULTS

At 3 or more years of follow-up no significant difference among irradiated and nonirradiated patients was detected. Most patients described optimal urinary continence and approximately one third had maintained potency after bilateral nerve-sparing prostatectomy. None of the patients who had undergone unilateral nerve-sparing surgery remained potent. Using a multivariable analysis, the significant predictors for maintaining potency were the status at 1 year postoperatively and bilateral versus unilateral nerve-sparing procedure.

CONCLUSIONS

Doses of adjuvant radiation therapy in the range used (45 to 54 Gy) did not affect the long-term pattern of maintenance of either function.

Comparison of outcomes of radical prostatectomy with and without adjuvant pelvic irradiation in patients with pathologic stage C (T3N0) adenocarcinoma of the prostate

Patients with localized adenocarcinoma of the prostate gland (CaP) are frequently (approximately 50%) found at radical prostatectomy to have extracapsular disease or positive surgical margins. The management of these patients is a subject of controversy because some question the impact of this manifestation of CaP on patient survival or disease-free survival. Between 1976 and 1991, 241 patients with pathologic stage C (T3N0) were treated in this medical center. Of these 241 patients, 201 (83%) received a planned postoperative pelvic irradiation consisting of 48 Gy given to the prostatic fossa, whereas 40 (17%) patients were treated with radical prostatectomy alone. The two study urologists selected these patients not to receive postoperative irradiation based on intraoperative findings and important prognostic factors. Comparison of treatment outcomes in these two treatment groups is a subject of this report. The 201 patients treated with surgery-radiotherapy (S+RT) combination had a higher pathologic stage, greater incidence of seminal vesicle involvement, p = 0.002, and higher mean and median preoperative prostate-specific antigen level, p < 0.0001, than the 40 surgery (S) alone patients. There was no significant difference in the incidence of higher Gleason's score by the treatment group, p = 0.14. In univariate analysis, there was no significant difference in survival, disease-free survival, and time to failure between the two treatment groups. In multivariate analysis after controlling for pathologic stage and Gleason's score, the 201 adjuvant radiotherapy patients were predicted to have recurrence at 68% (95% confidence interval 39%-118%) the rate of the 40 surgery-alone patients. Local recurrence with or without metastatic disease was found in 10% of surgery-alone patients as compared to 5% in those also receiving postoperative irradiation. Treatment tolerance was very good with minor radiotherapy complications only. There was no significant difference in the incidence of incontinence between the two treatment arms. In summary: (a) The use of moderate-dose postoperative radiotherapy was of low toxicity and it did not increase the incidence of incontinence. (b) Local recurrence was 5% in S+RT and 10% in S-alone patients. (c) In multivariate analysis, S+RT patients had 68% rate of recurrence of S-alone patients. (d) Adjuvant RT probably reduces the risk of recurrence in patients with poor prognostic factors. (e) These data need to be interpreted with caution because of the nonrandomized nature of the study.

Treatment outcome with adjuvant and salvage irradiation after radical prostatectomy for prostate cancer

OBJECTIVES

To determine the factors associated with outcome by reviewing our institution's experience treating patients with external beam radiation therapy (RT) after radical prostatectomy.

METHODS

Sixty-one patients received RT to the prostatic fossa after radical prostatectomy for prostate cancer (median dose 59.4 Gy). Thirty-eight patients received adjuvant RT within 6 months of surgery for adverse pathologic findings only. Therapeutic RT was administered to 23 patients either for a persistently elevated postoperative prostate-specific antigen (PSA) level (n = 2), a rising PSA level more than 6 months after surgery (n = 9), or a biopsy-proven local recurrence (n = 12). Preoperative and preradiation PSA values, Gleason score, pathologic findings, patient age, total RT dose, and indication for RT were analyzed for their impact on biochemical control. The median follow-up was 48 months.

RESULTS

Patients treated with adjuvant RT achieved 3 and 5-year biochemical control rates of 84% and 67%, respectively. Multiple clinical, pathologic, and treatment-related factors were analyzed for an association with biochemical control. No variable was associated with 5-year outcome. The 5-year actuarial rate of biochemical control for patients treated with therapeutic RT was 16%. Multiple clinical, pathologic, and treatment-related factors were analyzed for an association with biochemical control. Only a pre-RT PSA level of 2 ng/mL or less was associated with an improved rate of biochemical control at 3 years (80% versus 27%, P = 0.001). However, at 5 years, this difference was not statistically significant. A separate analysis was performed to determine the prognostic factors associated with outcome for the entire group of patients. Only the indication for RT (adjuvant versus therapeutic) was associated with 5-year outcome. Patients treated with adjuvant RT had a statistically significant improvement in 5-year actuarial rates of biochemical control (67% versus 16%, P <0.001) and disease-free survival (66% versus 46%, P = 0.037) but not in overall survival. There were no statistically significant differences between patient groups with respect to age, preoperative PSA, Gleason score, pathologic T stage, median follow-up, and total RT dose.

CONCLUSIONS

At our institution, patients treated with adjuvant RT after prostatectomy for adverse pathologic findings achieved excellent rates of biochemical control that were significantly better than that of similar patients treated therapeutically for persistent or rising PSA or clinical local recurrence.

Adjuvant radiotherapy in patients with pathologic Stage C (pT3N0) adenocarcinoma of the prostate

OBJECTIVES

This report is an update on the outcomes in the management of pathologic Stage C (T3N0) prostate cancer (CaP) with postoperative irradiation.

METHODS

Between 1976 and 1994, 311 patients with pathologic Stage C CaP were treated with radical prostatectomy. Pathologic stage was as follows: C1, 60 patients (19%), C2, 146 patients (47%), and C3, 105 patients (34%). Gleason score was 2 to 4 in 10 patients (3.2%), 5 to 6 in 121 (39%), 7 in 101 (32%), and 8 to 10 in 76 (24%); median prostate-specific antigen (PSA) level was 11.9 ng/mL. Postoperative irradiation consisted of a median dose of 48 Gy. Follow-up was up to 18 years (median 5).

RESULTS

The 10-year actuarial survival was 81% and 10-year disease-free survival was 51%. Pathologic stage and Gleason score were independently predictive of recurrence, each with P >0.001 after controlling for the other. Patients with pathologic Stage C3 and Gleason score 7 to 10 were in the worst prognostic category and had 5.4 times the risk of recurrence compared with patients with pathologic Stage C1-C2, Gleason score 2 to 6. Preoperative PSA was a good (P = 0.02) predictor of disease-free survival. Clinical recurrence was seen in 28 patients (9%), including 10 (3.2%) with local recurrence. PSA recurrence (PSA greater than 0.05 ng/mL) developed in 68 patients (22%).

CONCLUSIONS

With the known limitations of a nonrandomized clinical trial, on the basis of the experience of this study we recommend the use of moderate dose, limited-field postoperative radiotherapy in patients with pathologic Stage C disease with Gleason score greater than 4.

Effect of combined transient androgen deprivation and irradiation following radical prostatectomy for prostatic cancer

PURPOSE

To evaluate whether transient androgen deprivation improves outcome in patients irradiated after radical prostatectomy for locally advanced disease, persistent or rising postoperative prostate specific antigen (PSA), or local recurrence.

METHODS AND MATERIALS

Records of 105 consecutive patients who were treated with pelvic irradiation after radical retropubic prostatectomy between August 1985 and December 1995 were reviewed. Seventy-four patients received radiation alone (mean follow up: 4.6 years), and 31 received transient androgen blockade with a gonadotropin-releasing hormone agonist (4) androgen receptor blocker (1) or both (24) beginning 2 months prior to irradiation (mean follow-up 3.0 years) for a mean duration of 6 months. Two of these patients were excluded from further analysis because they received hormonal therapy for more than 1 year. Patients received a prostatic fossa dose of 60-70 Gy at 2 Gy per fraction; 48 patients also received pelvic nodal irradiation to a median dose of 50 Gy. Survival, freedom from clinical relapse (FFCR), and freedom from biochemical relapse (FFBR) were evaluated by the Kaplan-Meier method. Biochemical relapse was defined as two consecutive PSA measurements exceeding 0.07 ng/ml.

RESULTS

At 5 years after irradiation, actuarial survival for all patients was 92%, FFCR was 77%, and FFBR was 34%. FFBR was significantly better among patients who received transient androgen blockade before and during radiotherapy than among those treated with radiation alone (56 vs. 27% at 5 years, p = 0.004). FFCR was also superior for the combined treatment group (100 vs. 70% at 5 years, p = 0.014). Potential clinical prognostic factors before irradiation did not differ significantly between treatment groups, including tumor stage, summed Gleason histologic score, lymph node status, indication for treatment, and PSA levels before surgery or subsequent treatment. Multivariate analysis revealed that transient androgen deprivation was the only significant predictor for biochemical failure.

CONCLUSION

This retrospective study of irradiation after radical prostatectomy suggests that transient androgen blockade and irradiation may improve freedom from early biochemical and clinically evident relapse compared to radiotherapy alone, although more prolonged follow-up will be needed to assess durability of impact upon clinical recurrence and survival rates.