The role of bisphosphonates in the adjuvant setting for breast cancer.

Bone health is a critical issue in the management of women with breast cancer. Many women who develop breast cancer are postmenopausal, which already predisposes them to osteoporosis. Systemic treatments for breast cancer, including chemotherapy and endocrine therapy, decrease circulating levels of estrogen in both pre- and postmenopausal women, further accelerating the natural process of bone loss. The primary concern in breast cancer patients is that this accelerated bone loss, known as cancer treatment-induced bone loss (CTIBL), will lead to an increase in fractures, chronic pain, and loss of mobility. Bisphosphonates are highly effective at slowing the rate of bone loss in postmenopausal women with osteoporosis and at preventing skeletal-related events in women with metastatic breast cancer. Many studies are now focusing on the role of bisphosphonates in preventing CTIBL in the adjuvant setting. Both oral and intravenous bisphosphonates have shown promising activity in preventing CTIBL in patients receiving chemotherapy or hormonal therapy. In addition, emerging data indicate that the use of bisphosphonates in the adjuvant setting may prevent disease recurrence and prolong survival. Data from a number of ongoing trials will further elucidate the role of bisphosphonates in the adjuvant setting over the next few years.