Single-center developing country analysis of radium-223 therapy in prostate cancer-preliminary results

We reviewed the records of mCRPC patients treated with off-label use of Ra-223. Ra-223 efficiency in this non-study population was correlated to outcome measures overall survival (OS), progression-free survival (PFS), bone event-free survival, bone marrow failure (BMF), and disease-related biomarkers. There were no limits regarding the number of prior hormonal agents or chemotherapy received before or during Ra-223. Exclusion criteria consisted of baseline platelet counts below 50,000/mm³ and/or absolute neutrophil counts below 1,500/mm³. Twenty-eight patients received 130 cycles of Ra-223 between 2017 and 2018. The overall median OS was 15.6 months. However, in patients submitted to 4 or fewer cycles, the median OS was 9.1 months; in contrast, the median OS was 18.5 months in patients submitted to 5 or 6 cycles. There was a significant inverse correlation between the number of cycles and the occurrence of bone events (76.2% of the patients that completed 6 cycles did not present bone events, while 71.4% of the patients that had skeletal-related events were submitted to less than 6 cycles). 82.1% of the patients were submitted to concomitant therapies with no significant side effects. There was also a decrease in ALP and LDH levels throughout treatment. Radium-223 increased OS and decreased bone events, especially when patients were able to complete 5-6 cycles. The proper selection of patients is crucial to improve outcomes.