Abstract P3-11-12: Influence of Hormone Therapy Prior to Breast Cancer Diagnosis on Prognosis of Postmenopausal and Perimenopausal Breast Cancer Patients

Abstract

Abstract Introduction: Use of hormone therapy (HT) has been associated with higher incidence of hormone receptor positive breast cancer in postmenopausal women. However, it is unclear if breast cancers developing after HT use are different in course of disease and prognosis from tumors growing without prior exogenous hormone use. Methods: Women with hormone receptor positive breast cancer diagnosed between 1984 and 2006 at our university breast cancer center (n=1247) were analyzed in a single-center retrospective trial. Outcome data comparing overall survival, local and distant recurrence were extracted from the hospital cancer data base and the local breast cancer registry, as well as from primary care-giving gynecologists and by review of patient charts. Cases were stratified according to hormone therapy use before breast cancer diagnosis. This is the first analysis differentiating between perimenopausal and postmenopausal patients. Results: 1053 patients with hormone receptor positive non-metastasized invasive breast cancer were included in the final analysis. 198 (18.8%) women were premenopausal, 126 (12.0%) were perimenopausal and 729 (69.2%) were postmenopausal. Information on former HT use was available for 933 (88.6%) patients. 542 (51.4%) patients had never used HT, including 194 premenopausal patients. 324 (44.4%) postmenopausal and 67 (53.2%) perimenopausal women had used HT before breast cancer diagnosis. At time of first diagnosis there was a significantly higher rate of early stage and nodal negative disease in postmenopausal HT users versus non users (P<0.01 and p=0.02 respectively). In multivariate analysis, HT use prior to diagnosis in postmenopausal patients resulted in longer time to progression and longer overall survival (RR 0.84 and RR 0.70 with p=0.34 and p=0.07 respectively). In perimenopausal patients however, HT use prior to breast cancer diagnosis was associated with shorter time to progression and overall survival (RR 2.41 and RR 3.32 with p=0.99 and p=0.05 respectively). Higher BMI in perimenopausal women had a significant influence on prognosis with RR=1.14 for TTP and RR=1.23 for OS, whereas it had no effect in the postmenopausal group. Conclusion: According to this retrospective analysis, hormone therapy prior to breast cancer diagnosis has different effects on outcome parameters depending on patients’ menopausal state. Whereas in postmenopausal patients HT was associated with better prognosis, in perimenopausal women it might have detrimental effect. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-11-12.