[Retrospective practice-related care research study on therapy of mCPRC with radium-223 dichloride].

During phase III study ERA-223, patients under combination therapy with radium-223 and abiraterone showed an increased risk of bone fractures and a possible higher risk of death. This observation led to a change in the German therapeutic guidelines in 2018. Radium-223 is now only allowed as a third-line monotherapy (besides ADT) in patients with metastatic castration resistant prostate cancer (mCRPC) with symptomatic bone lesions without known visceral metastases or for patients with mCRPC, for whom no other available systematic therapy is suitable. Since almost no data on practice-related care research on the use of radium-223 exist, we consulted members of d-uo (German Uro-Oncologists) over their therapy algorithms. This study analysed data of patients treated with radium-223 between 2014 and 2019. It could be shown that 50% of mCRPC-patients had received radium-223 in the past as third-line therapy. Half of these were treated in combination with new androgen receptor targeted therapies (ARTA) and no increase in bone fractures was observed. This was most likely due to the additional use of bone protecting agents. Despite the late cancer stage, treatment response was seen in almost half of the patients.