Abiraterone acetate treatment in patients with castration-resistant prostate cancer with visceral metastases: a real-world experience.

In the pre-chemotherapy (CT) and post-CT settings of metastatic castration-resistant prostate cancer (mCRPC), abiraterone acetate plus prednisone (AAP) significantly extended median overall survival and radiographic progression-free survival (PFS) compared with prednisone alone. Yet, few data are available on therapy efficacy in the subgroup with visceral metastases, who represent a small population with poor prognosis. The aim of this study was to describe the clinical experience of AAP in patients with mCRPC with liver and/or lung metastases in real-world setting. We retrospectively reviewed the clinical records of patients with mCRPC with liver and/or lung metastases treated at the National Cancer Institute 'Fondazione G. Pascale' from September 2011 to May 2017. Co-primary end points were overall survival and radiographic PFS. Survival estimates were computed using Kaplan-Meier method. Secondary end points were response rate and safety. Of 143 patients with mCRPC treated, 18.9% (N=27) had visceral metastases: 85.2% (N=23) of the lung, 11.1% (N=3) of the liver and 3.7% (N=1) of both. Median PFS was 13.1 months [95% confidence interval (CI): 4.8-NA] in the pre-CT setting (N=11, median follow-up: 12.9 months), and 10.5 months (95% CI: 4.4-16.6) in the post-CT setting (N=16, median follow-up: 17.2 months). Pre-CT and post-CT patients with lung metastases had a median PFS of 16.5 months (95% CI: 4.3-NA) and 11.4 months (95% CI: 4.2-17.0), respectively. AAP tolerability was consistent with that previously reported in patients with mCRPC, without new safety concerns. Our finding provides preliminary evidence that AAP in real-world setting is a potential effective and safe therapeutic option for patients with mCRPC with a more advanced disease associated with the presence of visceral metastases, in both the pre-CT and post-CT settings.