Definitive radiation therapy in carcinoma of the prostate localized to the pelvis: experience at the Mallinckrodt Institute of Radiology.

Definitive radiation therapy was administered to 577 patients with histologically confirmed carcinoma of the prostate localized to the pelvis between January 1967 and December 1983. All patients were available for a minimal 3-year follow-up, and the median period of observation is 6.5 years. The actuarial survival without tumor in stages A2 and B at 5 years was 78% and at 10 years 60%. In stage C, the corresponding survival figures were 60% at 5 and 40% at 10 years. The overall actuarial survival in stage B patients was 76% at 5 and 56% at 10 years, which is similar to the life expectancy of a comparable cohort of normal males. In stage C, the actuarial survival was 65% at 5 and 35% at 10 years. The pelvic failure rate in stage A2 was 12% (5 of 41), 17% in stage B (31 of 185), 28% (93 of 328) in stage C, and 48% (11 of 23) in stage D1. Distant metastases were noted in 12% of the patients with stage A2, 20% stage B, 42% stage C, and 65% stage D1. In stage B, patients who had control of the pelvic tumor exhibited an 85% actuarial 5-year survival and a 60% one at 10 years. This compares with an actuarial survival of 30% at 5 and 10 years when there was evidence of pelvic recurrence alone or combined with distant metastases. In stage C patients with pelvic tumor control, actuarial survival was 81% at 5 and 50% at 10 years, in comparison with 25% at 5 and 10% at 10 years when there was development of pelvic recurrence or distant metastases or a combination of both. There was a strong correlation between the survival and appearance of distant metastases with the histologic degree of differentiation of the tumor in all stages. However, the probability of tumor control in the pelvis was not significantly correlated with this parameter. The administration of hormones concomitantly with radiation therapy did not significantly influence the probability of tumor control, appearance of distant metastases, or survival. Major sequelae of therapy were noted in 2.2% of the patients, whereas minor sequelae were observed in approximately 12% of the patients. Radiation therapy has been shown to be an effective therapeutic alternative to radical prostatectomy or hormonal manipulation in patients with carcinoma of the prostate.