Purpose: To determine the rate of tumor response and patterns of relapse following combined hormonal-radiation therapy of adenocarcinoma of the prostate and to measure the survival in a group of men with tumor metastatic to pelvic lymph nodes.
Methods and materials: 66 patients with adenocarcinoma of the prostate with pathologically confirmed pelvic lymph node involvement were treated with combined radiation therapy and hormonal therapy. An additional five patients declined hormonal therapy. The patients treated with combined therapy represented a group with locally advanced disease including 44 patients (67%) with T3 or T4 tumors and 51 patients (80%) had N2 or N3 lymph node metastases. The pelvic lymph nodes were treated to a dose of 45 Gy and the prostate was boosted to a dose of 65 to 71 Gy. Hormonal therapy began up to 2 months before radiation and continued indefinitely. Patients were allowed to select their hormonal therapy and could choose DES (2 patients), orchiectomy (21 patients), LHRH agonist (7 patients) or combined androgen blockade (34 patients).
Results: Median follow-up is 49 months (range 12 to 131 months) and 21 patients have been followed for longer than 5 years. There have been 15 recurrences the entire group including three local recurrences in the prostate, seven patients with distant metastases, four patients with biochemical recurrences without clinical evidence of disease, and one patient where the location was unknown. Two of the PSA recurrences occurred in patients who elected to discontinue hormones after less than 3 years of therapy. The overall survival at 5 and 8 years is 94 and 84%, the clinical disease free survival is 85 and 67%, and the biochemical disease-free survival is 78 and 47%. There was no increased toxicity of the combined modality regimen compared to the expected effects of radiation and hormonal therapy.
Conclusion: Combined hormonal and radiation therapy represents an effective treatment option for patients with adenocarcinoma of the prostate metastatic to pelvic lymph nodes. Combined modality therapy appears to extend the disease-free survival and allow patients to maintain their independent function.