Treatment strategies for skeletal complications of cancer.

Skeletal complications are a common result of many cancers, particularly of multiple myeloma and bone metastases of solid tumors originating in the breast, prostate or lung. A number of treatment options are available, including radiotherapy, radiopharmaceuticals, surgery and chemotherapy. Recently, bisphosphonates have emerged as a promising new treatment option for bone complications of cancer. These agents are potent inhibitors of osteoclast activity that bind to the bone matrix, are released during bone resorption, and are subsequently internalized by osteoclasts, where they interfere with biochemical pathways and induce osteoclast apoptosis. Bisphosphonates also antagonize osteoclastogenesis and promote the differentiation of osteoblasts. As a result, bisphosphonates inhibit tumor-induced osteolysis and reduce skeletal morbidity. Bisphosphonates are generally well tolerated, although they have recently been associated with osteonecrosis of the jaw, a painful and debilitating side effect that is only beginning to be understood. Despite this concern, bisphosphonates are an important tool in the management of skeletal complications of cancer, providing benefits for the treatment of hypercalcemia, osteolytic lesions and fractures, as well as offering amelioration of pain and improvement in quality of life.