Effect of calcitonin on anastrozole-induced bone pain during aromatase inhibitor therapy for breast cancer.

This study aimed to investigate calcitonin as an effective therapy for osteoporosis in patients with bone pain during the anastrozole treatment of breast cancer. Ninety-one patients, who were on anastrozole treatment for breast cancer and also suffered anastrozole-induced bone pain, were randomly divided into two groups: the calcitonin group received salmon calcitonin and Caltrate D, and the control group received Caltrate D. All patients were evaluated by the visual analogue scale (VAS) and underwent the dual energy x-ray absorptiometry test for bone mineral density (BMD), and serum osteocalcin (BGP), alkaline phosphatase (ALP), calcium (Ca), and phosphorus (P) were measured at three months before and after the treatment. Significant differences in serum Ca, P, BGP, and ALP were found in each group between before and after treatment (P < 0.05), while no differences between the calcitonin and control groups were found. No difference was observed in femur BMD between the two groups, or between before and after treatment in each group. There was a significant difference in spine BMD between before and after treatment in the control group (P < 0.05) but not in the calcitonin group, while no difference was found between the calcitonin and control groups. Futhermore, VAS score significantly declined in each group after treatment (P < 0.05), but much more in the calcitonin group than the control group (P < 0.05). Our finding suggests that calcitonin may alleviate bone pain during the anastrozole treatment of breast cancer but has no effect on bone loss during cancer treatment.