Long-term results of adjuvant hormonal therapy plus radiotherapy following radical prostatectomy for patients with pT3N0 or pT3N1 prostate cancer

BACKGROUND: The objective of the present study was to evaluate the efficacy of adjuvant androgen suppression in conjunction with external beam irradiation after radical prostatectomy in patients with pathologically confirmed extraprostatic disease. METHODS: Between July 1988 and October 1999, 38 patients with pT3N0 or pT3N1 prostate cancer received adjuvant hormonal therapy and external beam irradiation following radical retropubic prostatectomy and pelvic lymphadenectomy. Administration of luteinizing hormone-releasing hormone analog or castration were initiated as an adjuvant androgen suppression within 4 weeks after surgery, whereas pelvic irradiation was performed at a median dose of 50 G within 3 months after surgery. The prognostic advantage of this combined adjuvant therapy was analyzed. RESULTS: During the median observation period of 92 months, biochemical recurrence occurred in four of the 38 patients and five patients died. Of these five patients, only one died of prostate cancer progression. The 10-year biochemical recurrence-free, cancer-specific and overall survival rates of the 38 patients were 86.7%, 90.9% and 78.7%, respectively. Among several factors examined, only tumor grade was significantly associated with biochemical recurrence-free survival in these patients; however, there were no factors that were independent predictors for biochemical recurrence, based on multivariate analysis. Furthermore, biochemical recurrence-free survival in the 38 patients was significantly superior to that in 54 patients with locally advanced disease who did not receive any postoperative therapies until biochemical recurrence; however, there was no significant difference in cancer-specific and overall survival between these two groups. CONCLUSION: Despite retrospective analysis with a relatively small number of patients, results of the present study suggest favorable effects of the combined adjuvant treatments with androgen ablation and pelvic irradiation on cancer control for patients with pT3N0 or pT3N1 disease. However, considering the absence of a significant difference in cancer-specific and overall survival between patients with and without adjuvant treatments, it might not be necessary to routinely perform combined hormonal and radiation therapies in an adjuvant setting for pT3N0 or pT3N1 prostate cancer.