Abstract
Treatment of postmenopausal women with breast cancer using aromatase inhibitors (AIs) is widely accepted as adjuvant therapy, but the negative effects of AIs on bone mineral density (BMD) are recognized. We evaluated changes in BMD of patients receiving anastrozole (ANA) as adjuvant therapy for 5 years. The study included 37 patients divided into the following four treatment groups : N-group (n=8), given ANA only ; V-group (n=5), ANA with vitamin D (Vit D) ; VB-group (n=10), ANA with Vit D first changed to bisphosphonates (Bis) ; and the B-group (n=14), ANA with Bis. Forearm BMD was assessed at baseline and then every year for 5 years in total. The percentage changes in BMD from baseline to 5 years were as follows : N-group, -11.7% ; V-group, -14.1% ; VB-group, -6.5% ; and B-group, +1.6%.
While the BMD of V-group decreased most among the four groups, in response to changing Vit D to Bis, the degree of decrease was improved in the VB-group and it was possible to maintain BMD with addition of Bis from the start of adjuvant ANA in B-group. Our results suggest that BMD decline can be prevented by using Bis in Japanese postmenopausal women with hormone receptor-positive breast cancer scheduled to receive ANA.
