Bisphosphonates: their evolving role in the management of prostate cancer-related bone disease

The use of androgen deprivation therapy has increased because of its use as part of multimodality therapy for high-risk early stage disease and in recurrent nonmetastatic disease. Hormonal therapy is associated with secondary osteoporosis and increased skeletal morbidity. Furthermore, in patients with established bone metastases, osseous complications are a significant problem. Bisphosphonates have been investigated in the prevention of bone density loss and skeletal morbidity. Results of these studies are now becoming available.

Data are emerging that demonstrate that bisphosphonates can prevent skeletal morbidity, such as pathologic fractures and spinal cord compression in men with hormone-refractory prostate cancer. The early use of bisphosphonates has also been shown to prevent bone loss due to androgen deprivation therapy. Current third-generation bisphosphonates are several hundred times more potent than their predecessors. Evidence is emerging that these drugs not only inhibit bone resorption but also are cytotoxic to prostate cancer cells.

Bisphosphonates are assuming a prominent ancillary role in prostate cancer therapy through their ability to prevent skeletal morbidity. Their potential to interfere with the formation of osseous tumor deposits has lead to investigations into the capacity of these drugs to prevent bone metastasis.