TNFSF11 and neoplasm: Bone is the most frequent metastatic site for breast cancer, and is invaded in 70% of metastatic patients.(58) Although osteoclastic inhibitors such as bisphosphonates and the RANKL inhibitor denosumab are approved in the treatment of skeletal metastases to limit bone loss and reduce skeletal‐related events,(19) these drugs only target the “soil” (bone microenvironment) aspect of the skeletal metastases and do not address the “seed” portion of the equation; ie, the invading tumor cells.