Incidence and Predictive Factors for Recovery of Ovarian Function in Amenorrheic Women in Their 40s Treated With Letrozole

PurposeThis prospective study assessed the impact of 2 years of aromatase inhibitor (AI) therapy on the incidence of ovarian function recovery (OFR) in women age 40 to 49 with estrogen receptor–positive breast cancer who were premenopausal at diagnosis and who underwent chemotherapy-induced amenorrhea during adjuvant treatment.Patients and MethodsWomen age 40 to 49 with estrogen receptor–positive breast cancer who had ceased menstruating with adjuvant cyclophosphamide-based chemotherapy, had postmenopausal serum estradiol (E2), and had received tamoxifen for ≥ 1 year were treated with letrozole (2.5 mg) daily for ≥ 2 years. Serum follicle-stimulating hormone (FSH) and E2 were measured at baseline and over 2 years. A general linear model was used to assess serial FSH by OFR. Logistic regression was used to assess baseline predictors and OFR.ResultsThe study enrolled 177 women (145 women age 45 to 49 years and 32 women age 40 to 44 years). Of 173 evaluable patients, 67 (39%; 95% CI, 31% to 46%) regained ova...