A 70-year-old man with metastatic castration-resistant prostate cancer (mCRPC) has progressed on abiraterone. He has no visceral metastases but has extensive bone disease. Which of the following agents targets bone metastases and has been shown to improve overall survival in mCRPC with bone metastases but no visceral metastases?
- A Zoledronic acid
- B Radium-223 (Xofigo) ✓
- C Denosumab
- D Cabazitaxel
Correct answer: B. Radium-223 (Xofigo)
Explanation
Radium-223 (Ra-223 dichloride / Xofigo) is an alpha-emitting radiopharmaceutical that mimics calcium and selectively concentrates in areas of osteoblastic bone metastases. The ALSYMPCA trial demonstrated that radium-223 significantly improves overall survival (14.9 vs 11.3 months) and delays symptomatic skeletal events in mCRPC patients with bone metastases but no visceral metastases. It is the only bone-targeting agent proven to extend overall survival in mCRPC. Zoledronic acid and denosumab prevent skeletal-related events but do not improve OS.
Reference: Bailey & Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.