Safety and clinical outcomes of abiraterone acetate (aa) after docetaxel (doc) in octogenarians with metastatic castration-resistant prostate cancer (mcrpc)

Abstract

Background: AA demonstrated to significantly prolong survival of mCRPC patients ( pts) after first line DOC. Although its favorable toxicity profile, the administration of AA in very old patients, who usually show reduced physiological reserves and multiple comorbidities, could raise raises questions about its safety due to the risk of metabolic and cardiovascular side effects in very old pts. We assessed the tolerability of AA in a cohort of mCRPC octogenarians enrolled in the Italian AA NPP, and evaluated their clinical outcomes. Patients and methods: We retrospectively reviewed the clinical records of all pts treated with AA for mCRPC by NPP in our Institutions. All pts have been previously treated with a DOC‐based first line chemotherapy and received the standard AA dose of 1,000 mg po daily plus prednisone 10 mg po daily. For each pt we recorded the pre and post‐AA clinical history, the AA treatment details toxicities and clinical outcomes and separately assessed the pts aged = 80 years. Results: Among the overall population of 265 pts, we found 47 octogenarians: the median age was 82 yrs (range 80‐91). The median exposure to AA was 8 mos with major toxicity consisting of grade 3‐4 anemia, nausea, diarrhea, fatigue, bone pain, constipation, and edema, each observed in one pt respectively. In these very old men the PSA response rate was 48.9%, and the median progression‐free and overall survival were respectively 8 and 18 months. In comparison with younger patients, there were no significant differences in both toxicities and clinical outcomes. Conclusions: Our data suggests that AA is active and safe also in octogenarians and leads to outcomes that are similar to those observed in younger patients, thus confirming that AA is a manageable therapeutic option in this patient population.