Chemoprevention Agents to Reduce Mammographic Breast Density in Premenopausal Women: A Systematic Review of Clinical Trials.

A limited number of chemoprevention agents have been shown to reduce MBD in premenopausal women. Identification of new and well-tolerated chemoprevention agents targeting MBD and larger studies to confirm agents that have been studied in small trials are urgent priorities for primary breast cancer prevention in premenopausal women with dense breasts.