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

Abstract

A progress report on the treatment of 15 patients with Stage B and 97 patients with Stage C histologically proven adenocarcinoma of the prostate shows that the cumulative absolute 5-year survival rate is approximately 60% for patients with Stage B and 42% for those with Stage C. Patients received 7000 rads to the prostate, 6000 rads to the external iliac and hypogastric pelvic nodes, and 5000 rads to the common iliac nodes; 22 MeV Betatron photons were used with progressively decreasing AP-PA fields. The local control rate is 82%. Most of the patients failing have developed distant metastases, particularly those in the poorly differentiated carcinoma group. The morbidity of this treatment is acceptable to physicians and patients; the major complications occurred in approximately 5% of patients, and none of them were fatal. The 5-year survival rates for patients with well- and moderately differentiated tumors are significantly better (50-65%) than for those with poorly differentiated tumors (15%). There was no significant difference in survival between a group of 41 patients treated with radiation alone compared with 50 patients treated with a combination of irradiation and hormonal therapy. From the data currently available, it seems that definitive radiation therapy should be adequately evaluated in the treatment of patients with carcinoma of the prostate localized to the pelvis, before hormonal therapy is instituted. In addition, the advisability of staging laparotomies must remain uncertain until the information obtained from such procedures can be directly applied to improving survival. In view of the poor prognosis and high propensity for distant dissemination in patients with poorly differentiated carcinoma of the prostate, it is felt that clinical trials are needed to evaluate the potential use of cytotoxic agents combined with pelvic irradiation as a cytoreductive agent.