Purpose: Mortality from breast cancer has decreased in large part because of adjuvant chemotherapy. Sequelae of therapy include ovarian failure and bone loss, loss that would increase these patients' risk of fracture with aging. In this study, we assessed the efficacy of pamidronate in preventing such loss.
Patients and methods: The study was a 1-yr randomized, double-blind, placebo-controlled trial comparing pamidronate 60 mg iv every 3 months with placebo in 40 premenopausal women with newly diagnosed breast cancer. Bone mineral density (BMD) of the spine and hip and remodeling markers were monitored over 1 yr.
Results: Over half of the subjects became amenorrheic, and those who did were 4 yr older than those who did not (P = 0.02). The mean difference in percent change in BMD at 12 months between the two treatment groups was 5.1% at the lumbar spine (P = 0.002) in the overall study group and 5% at the lumbar spine and 5.2% at the total hip in the amenorrheic subgroup (P < 0.03). Biochemical markers of bone remodeling did not differ between the two treatment groups, and treatment was well tolerated.
Conclusion: Chemotherapy-induced amenorrhea is common with ensuing bone loss at the spine and hip. Pamidronate prevented bone loss at the spine and hip and was well tolerated.