Clinical and Biochemical Evidence of Control of Prostate Cancer at 5 Years After External Beam Radiation

Abstract

We demonstrate the 5-year survival rate for patients with prostate cancer treated by irradiation, the value of the conformal technique and prostate specific antigen (PSA) doubling times after irradiation. The outcome of 502 consecutive patients with stages T1 to T3 prostate cancer treated by irradiation alone is reported. PSA doubling times before and after failure are reported for 13 patients and posttreatment PSA doubling times are reported for 93 consecutive patients in whom radiation failed. The actuarial survival with biochemical freedom from disease (PSA nadir 1.5 or less not increasing) at 5 years was 44% for all patients, 50% for the conformal treatment group and 39% for the conventional therapy group. PSA doubling times after radiation failure were variable, with 42% greater than 12 months. The 5-year survival rate for patients with prostate cancer treated by irradiation is excellent. The conformal technique is superior to conventional therapy and there is no evidence that irradiation accelerates the growth rate of prostate cancer.