Tamoxifen protects against steroid-induced bone loss.

As part of a clinical trial of adjuvant endocrine treatment in postmenopausal women with operable breast cancer serial bone density measurements have been performed by dual photon absorptiometry. Tamoxifen alone was given to 26 women, and 20 received additional prednisolone. By 24 months after entry there was no significant difference between mean bone density of the two groups, nor any significant change from baseline levels. There was a mean gain of 0.46% in the tamoxifen group and 1.95% in those given additional prednisolone. Thus the predicted steroid-induced bone loss was inhibited by tamoxifen. This may be of more general use in prevention of osteoporosis in patients requiring long-term steroid treatment.