Postoperative radiotherapy after radical prostatectomy for prostate carcinoma: the experience of the Brescia Radium Institute

Abstract

The purpose of this study was to evaluate the efficacy of postoperative radiotherapy in reducing the incidence of prostate carcinoma (PCa) recurrences after radical prostatectomy (RP), define the importance of the time interval between surgery and radiotherapy for prognosis and the toxicity of the treatment in comparison with radiotherapy or surgery alone. We examined 97 patients who consecutively underwent postoperative radiotherapy after RP between 1980 and 2003. The treatment was considered "adjuvant" if was conducted less than 6 months after RP, if there was no macroscopic residual disease and if there was no progressive increase in serum prostate-specific antigen (PSA) and "salvage" if performed more than 6 months after RP, for the presence of macroscopic recurrence or with rising PSA. Radiotherapy was salvage in 56 patients and adjuvant in 41. Age range was 60-70 years in 80% of patients, and the Karnofsky index was over 80 in 78% of cases. Histology revealed extracapsular spread in 60% of patients. Preradiotherapy PSA was higher than 1 ng/ml in 36%. Radiotherapy was performed on the surgical bed only in 80%, and the total dose was 70 Gy in 62% of cases. Recurrence-free survival (RFS) at 5 years and 10 years was 53+/-8% and 32+/-14.2%, respectively, for the whole sample; 76+/-9% and 38+/-2.7% for patients treated with adjuvant radiotherapy and 36+/-10% and 28+/-10% for those treated with salvage radiotherapy (p<0.01). Moreover, the 5-year RFS was better in the group treated with adjuvant radiotherapy and PSA less than or equal to 1 ng/ml (p<0.05). Treatment toxicity was acceptable. Postoperative radiotherapy improves RFS and reduces the risk of local recurrence. The best results are obtained with early postoperative treatment ("adjuvant"); adjuvant radiotherapy of high-risk forms yields better results if performed with PSA less than or equal to 1 ng/ml.