Abstract P5-11-08: Effects of Exemestane or Tamoxifen on Bone Health within the Tamoxifen Exemestane Adjuvant Multinational (TEAM) Trial: A Meta-Analysis

Background: TEAM is the largest AI phase III trial comparing exemestane with tamoxifen followed by exemestane as adjuvant breast cancer therapy in postmenopausal women. We performed a meta-analysis of three randomized sub-studies of the TEAM trial conducted in Germany, the Netherlands/Belgium and the United States to determine the effects on bone health. Methods: Patients were randomised to exemestane or tamoxifen as adjuvant therapy for hormone receptor-positive breast cancer. Bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry at baseline and after 6, 12 and 24 months’ treatment. Bone turnover markers were also measured. Results: 412 patients were evaluable. Patients in the tamoxifen group showed a mean increase in lumbar spine BMD of 1.2% from baseline to month 12 and 0.2% to month 24. Patients in the exemestane group showed a mean decrease from baseline of 2.6% after 12 months and 3.5% after 24 months. There were significant differences in the changes in BMD at the lumbar spine between treatment groups (P Conclusions: After 24 months, exemestane treatment resulted in decreases in BMD and increases in bone turnover markers. In contrast, BMD was increased and bone turnover markers were decreased with tamoxifen. BMD and bone turnover changes appeared to stabilise after initial treatment. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-11-08.