Fracture risk and survival outcomes in metastatic castration-resistant prostate cancer patients sequentially treated with abiraterone acetate and RADIUM-223.

Abstract

To evaluate the fracture risk and survival outcomes in patients with metastatic castration-resistant prostate cancer (mCRPC) who received sequentially abiraterone acetate (AA) and radium 223 [223Ra]RaCl₂ in the daily clinical practice. We retrospectively reviewed the records of mCRPC patients who received [223Ra]RaCl₂ immediately after progressing during an AA treatment line in everyday clinical practice. We reviewed data of a consecutive series of 94 mCRPC patients. Most of the patients (85.1%) received [223Ra]RaCl₂ as second- or third-line treatment. [223Ra]RaCl₂ treatment was well-tolerated; there were only four cases of grade 3 anaemia, two cases of grade 3 leukopenia and one case of grade 3 neutropenia. The overall fracture rate is 2.1%; one fracture was recorded during the course of [223Ra]RaCl₂ treatment, and one was recorded 1 month after its end. The fractures both occurred at metastatic sites. Median OS from [223Ra]RaCl₂ start was more than 14 months regardless of the treatment line when [223Ra]RaCl₂ was administered. The findings of this study show that the treatment with [223Ra]RaCl₂ immediately after AA was active and safe with a very low risk of a fracture. Thus, the present observational report makes a valuable contribution to the current debate concerning the risks and benefits of including [223Ra]RaCl₂ in the therapeutic algorithm.