Combining abiraterone and radiotherapy in prostate cancer patients who progressed during abiraterone therapy

Background/Aim: This multicenter, retrospective, 'field-practice' study investigated treatment outcomes of ongoing abiraterone therapy with the addition of radiotherapy (RT)-initiated for oligoprogression or with a palliative intent. Patients and Methods: Consecutive patients affected by metastatic castration-resistant prostate cancer (mCRPC) treated with abiraterone acetate were considered if they had received RT after the initiation of abiraterone treatment. Results: A total of 32 patients were enrolled in the study. Median duration of abiraterone treatment was 13.0 months (range=3.8-40.9 months). Median duration of abiraterone treatment before RT was 5.9 months (range=0.4-40.0 months), and 7.2 months after RT (range=0.1-29.7 months). Median progression-free survival (PFS) was 12.6 months (95%CI=10.5-14.7) from the initiation of abiraterone treatment. From RT administration, PFS was 9.6 months (95%CI=6.4-12.9). Median overall survival (OS) since abiraterone initiation was 18.9 months (95%CI=4.7-33.0). Conclusion: RT prolongs abiraterone treatment in mCRPC patients leading to better clinical outcomes with this molecule.