Management of Premenopausal Women with Neoadjuvant Endocrine Therapy: A Single-Institution Experience

In postmenopausal women with hormone receptor (HR)-positive breast cancer, neoadjuvant endocrine therapy (ET) provides effective downstaging of tumor for improved surgical outcome and offers an important advantage of assessing tumor endocrine responsiveness for individualized therapy in the adjuvant setting. Although approximately 60 % of breast cancers in premenopausal women are HR positive, the role of neoadjuvant ET in this population is not well defined. We identified 162 patients with stage I-III estrogen receptor-positive breast cancer treated with neoadjuvant ET between 2003 and 2012. Of this group, 17 patients were premenopausal. Data included patient/tumor characteristics, surgical, systemic, and radiation treatment received, and outcomes. Descriptive statistics were used for data summary. The cohort included 17 patients with a mean age of 46.2 years (range 39-53 years). Patients were treated with a combination of gonadotrophic-releasing hormone agonist with either an aromatase inhibitor (n = 14) or tamoxifen (n = 3) for 4-6 months. Among the premenopausal patients, six underwent breast-conserving therapy, with 3 of 6 (50.0 %) having positive margins. Adjuvant chemotherapy was recommended for 13 (76.5 %), and adjuvant radiotherapy was recommended for 13 (76.5 %). Of the 17 premenopausal women, 11 had a clinical response based on response evaluation criteria in solid tumors (RECIST) of a decrease in tumor size of 30 % (64.7 %); this is similar to that of postmenopausal women, where 85 of 145 (58.6 %) patients showed a clinical response. As with all neoadjuvant systemic interventions, we identified those with disease that did and did not respond to ET, emphasizing the heterogeneity of HR-positive breast cancers. The response rate of premenopausal women to neoadjuvant ET is similar to that of postmenopausal women.