Biochemical control of the combination of cyclooxygenase‐2 inhibitor and 125I‐brachytherapy for prostate cancer: Post hoc analysis of an open‐label controlled randomized trial.

Objectives: To evaluate the use of cyclooxygenase‐2 inhibitors in patients receiving low‐dose‐rate brachytherapy for prostate cancer. Methods: A total of 310 patients with prostate cancer (cT1c‐3aN0M0) who received low‐dose‐rate brachytherapy between May 2010 and July 2013 were enrolled and allocated to one of the two treatment groups (tamsulosin alone 0.2 mg/day for 6 months vs tamsulosin 0.2 mg/day for 6 months plus celecoxib 200 mg/day for 3 months). The primary end‐point was the chronological change in international prostate symptom score, and the number of patients was assessed for the primary end‐point. Biochemical recurrence‐free, cancer‐specific survival and overall survival rates 5 years after the last patient received low‐dose‐rate brachytherapy were retrospectively examined. Results: The median follow‐up period after low‐dose‐rate brachytherapy was 72.0 months (range 3–99 months). A total of 12 (3.9%) patients experienced biochemical recurrence. The biochemical recurrence‐free rate in the celecoxib group (5‐year biochemical recurrence‐free rate 98.5%) was significantly better (log–rank test P = 0.023, 95% confidence interval 0.07–0.63, hazard ratio 0.20) than that in the tamsulosin group (5‐year biochemical recurrence‐free rate 93.4%). None of the patients died from prostate cancer. However, 14 (4.5%) patients died of other causes. No significant difference was observed in terms of overall survival between the celecoxib and tamsulosin groups. Conclusions: The combination of cyclooxygenase‐2 inhibitor and low‐dose‐rate brachytherapy can contribute to a better biochemical control of prostate cancer. [ABSTRACT FROM AUTHOR]