Adjuvant bisphosphonates: a new standard of care?

Clinical studies show that bisphosphonates can ameliorate bone loss from adjuvant breast cancer therapies, with suggestions of anticancer benefit. Recent long-term studies have provided additional support for a clinical benefit from bisphosphonates in the adjuvant breast cancer setting and suggest that adjuvant bisphosphonates might be an appropriate standard of care. This review evaluates the recent clinical evidence for the effectiveness of adjuvant bisphosphonate therapy in breast cancer.

Oral bisphosphonates did not affect breast cancer recurrence in premenopausal women and had inconsistent results in postmenopausal women. The intravenous bisphosphonate zoledronic acid demonstrated clear disease-free and overall survival benefits in patient subgroups expected to have low estrogen levels: premenopausal patients undergoing ovarian suppression and postmenopausal women who were 5 years past menopause or 60-65 years or older.

Current clinical evidence is insufficient to support using oral bisphosphonates as a standard adjuvant therapy in breast cancer; however, additional studies are warranted. In contrast, zoledronic acid may be considered a new standard of care in adjuvant breast cancer, at least for some postmenopausal women and premenopausal women undergoing ovarian suppression.