[Osteoprotection in patients with bone metastatic castration-resistant prostate cancer (mCRPC): real-world data from...

Patients with bone metastasis due to prostate cancer often present allover reduced bone mineral density. Additionally, patients with bone metastatic castration-resistant prostate cancer (mCRPC) have a relevant risk for skeletal-related events (SRE). We herein present real-world data (RWD) regarding osteoprotection in mCRPC patients with bone metastasis treated by German urologists in private practice.

This is a questionnaire-based study including members of d-uo ("Deutsche Uro-Onkologen", German uro-oncologists). All patients with histologically confirmed prostate cancer seen at least once in the surveyed urology practice between July 2019 and June 2020 were included. Questions included start, type and duration of osteoprotection as well as supplementation with calcium and vitamin D.

Between July 2019 and June 2020, a total of 3,692 patients with prostate cancer were seen at least once in 15 urology practices. There were 410 mCRPC patients (11.1%) with bone metastasis. Osteoprotection with denosumab or a bisphosphonate to prevent SRE was applied in 274/410 mCRPC patients (66.4%) with bone metastasis. In patients receiving osteoprotection, denosumab was chosen for 67.9% of patients and a bisphosphonate was chosen for 32.1%. Supplementation with calcium and vitamin D was performed in 93.4% of the patients. The median duration of treatment was 25.3 months for denosumab compared with 39.6 months for bisphosphonates.

Patients with mCRPC with bone metastasis received osteoprotection in 2/3 of cases. Of these, 2/3 received denosumab and 1/3 received a bisphosphonate. The majority of patients were also treated with calcium and vitamin D. According to guideline recommendations regarding osteoprotection in mCRPC patients with bone metastasis, our RWD data showed some lack of guideline adherence.