The incidence of invasive breast cancer among women prescribed testosterone for low libido

Abstract

Introduction. Although the efficacy of testosterone for the treatment of hypoactive sexual desire disorder is well established, the effect of testosterone therapy on breast cancer risk remains uncertain. Aim. The incidence of invasive breast cancer among past and current testosterone users. Methods. Retrospective cohort study of 631 women ever treated with testosterone between January 1989 and December 2007 in a clinical endocrinology practice. Main Outcome Measure. The incidence of invasive breast cancer since first exposure, and the standardized incidence rate ratio (IRR) calculated using Australian age-specific incidence rates for 2005. Results. The mean age of the women at first exposure..