An Evaluation of Response to Therapy in Patients Undergoing Radiotherapy or Surgery in the Treatment of Prostate Cancer.

Objective: This study compared biochemical recurrence (BR), biochemical recurrence-free survival (BRFS) and overall survival (OS) rates and therapeutic methods in patients undergoing definitive radiotherapy (RT) or radical prostatectomy (RP) because of diagnosis of prostate cancer.

Method: Files of 128 patients undergoing RP (n=82) or RT (n=46), who did not receive salvage therapy, and with serum PSA levels monitored three-monthly for at least two years were examined retrospectively. Patients were assigned into low, intermediate and high risk groups based on D'Amico risk classifications. RP was performed in the surgical arm and in the RT arm 70-74 Gy RT were applied using 3D conformal RT technique.

Results: BR was not detected among low risk group patients over 10-year follow-up. No difference was determined between the treatment arms in BR in the intermediate risk patients, while the RT arm was statistically significantly better among the high risk patients (p=0.04). OS rates in the low, intermediate, and high risk groups were 97.1%, 93.8%, and 92.3%, respectively, in the RP, and 81.8%, 92.9%, and 90.5%, respectively, in RT (p>0.05) group. BRFS rates in the intermediate and high risk groups were 92.3%, vs 95.2% in RP, and 79.6%, vs 81.6% in RT (p>0.05).

Conclusion: There was no significant difference between BRFS and OS rates in the two arms of prostate cancer treatment, although RT was better in the high risk group patients in terms of BR. Longer-term studies involving high-dose RT techniques applied with maximum protection of normal tissue and supporting the effectiveness of RT are needed.