Effect of Celecoxib Combined With Low-Dose-Rate Brachytherapy on Long-Term Oncological Outcomes and Quality of Life in Prostate Cancer: Post Hoc Analysis of an Open-Label Controlled Randomized Trial.

BACKGROUND: Long-term clinical data evaluating oncological outcomes and patient-reported quality of life (QOL) after combining celecoxib with radiotherapy are lacking. Therefore, we aimed to assess oncological outcomes and QOL with extended follow-up to determine the effect of celecoxib combined with low-dose-rate brachytherapy (LDR-BT) in the present study. PATIENTS AND METHODS: An open-label, randomized study was conducted to evaluate the effect of COX-2 inhibitors, specifically celecoxib, on preventing acute genitourinary system toxicity between May 2010 and July 2013, with a negative result for the primary endpoint. In the control group (n = 156), tamsulosin was administered at 0.2 mg/day for 6 months, and in the celecoxib group (n = 154), tamsulosin at 0.2 mg/day for 6 months was combined with celecoxib at 200 mg/day for 3 months. Oncological outcomes and QOL (Expanded Prostate Cancer Index Composite) were compared between the two groups in this post hoc extended follow-up analysis. RESULTS: The median follow-up time after LDR-BT was 120 months (interquartile range, 98-134 months). The cumulative incidences of biochemical recurrence (BCR) and metastasis were significantly lower in the celecoxib group than those in the control group (10-year cumulative incidence of BCR: 1.5% vs 9.0%, p = 0.006; 10-year cumulative incidence of metastasis: 0% vs 5.7%, p = 0.01). There were no significant differences between the two groups in prostate cancer-specific survival (p = 0.06) or overall survival (p = 0.64). Regarding QOL, there was no significant difference between the two groups in score changes before treatment in the urinary, bowel, sexual, or hormonal domain at 24, 36, 48, 60, or 120 months after LDR-BT. CONCLUSION: Celecoxib combined with LDR-BT for prostate cancer was associated with lower cumulative incidence of BCR and metastasis, although QOL impairment was not ameliorated. CLINICAL TRIAL REGISTRATION: UMIN000003649.