A long-term study of the efficacy of treatment of localized prostate cancer

This paper presents a retrospective comparison of patients undergoing treatment for clinically localized prostate cancer. We reviewed the age, grade, and stage at diagnosis as well as the survival and recurrence rates of 222 patients treated for carcinoma of the prostate with either radical prostatectomy (RP) or radiotherapy (XRT) at four Army medical centers. Mean follow-up was 8.02 years (range 0.026–32.5 years). Stage and grade were similar in patients receiving either RP or XRT. Kaplan-Meier estimates showed that patients who underwent RP had a significantly greater disease-specific survival (p = 0.0001) and a significantly lower rate of distant metastases (p = 0.006) than did those who received XRT. There was no significant difference in the rate of local progression (p = 0.276) or in the mean time to local progression (XRT = 3.5, RP = 4.0 years) or to distant metastases (XRT = 3.79, RP = 4.52 years). Cox proportional hazards model incorporating age, stage, grade, and treatment type demonstrated that those patients who received XRT had more than two times the risk of dying of their disease than did those who underwent RP (risk ratio = 2.37; 95% confidence interval = 1.49–3.76). These data in similar groups of patients suggest that metastasis-free survival is improved in those who receive RP compared with XRT and that this translates into an enhanced survival advantage. Further study of larger groups of patients stratified by risk factors in randomized, prospective trials with longer follow-up will improve our ability to determine the best treatment for clinically localized prostate cancer.