Adjuvant hormonal therapy in young breast cancer patients

Abstract

1 ISSN 1758-1923 10.2217/BMT.13.67 © 2014 Future Medicine Ltd Breast Cancer Manage. (2014) 3(1), 1–4 Breast cancer arising at a young age is a complex condition, requiring multidisciplinary and personalized approaches to manage the specific issues related not only to optimal adjuvant treatments, but also to other important quality-of-life issues, such as bone health, premature menopause, fertility preservation and long-term cognitive function [1]. Approximately 5% of women with breast cancer are diagnosed before the age of 40 years, but the incidence appears to be on the rise [101]. In the adjuvant setting, 5 years of tamoxifen treatment is considered the current standard of care in managing young women with an endocrine-sensitive disease. Based on the meta-analysis of the Early Breast Cancer Trialists’ Collaborative Group (EBCTCG), 5 years of tamoxifen significantly reduced breast cancer mortality throughout the first 15 years, with a greater effect when tamoxifen was given for 5 years compared with 2 years [2]. Nevertheless, in the past decade several questions were raised and remain unanswered in the field of adjuvant endocrine treatment of young breast cancer patients, including the optimal duration of adjuvant endocrine therapy, the addition of luteinizing hormone-releasing hormone analogs (LHRHa) to standard tamoxifen and its duration, and the use of aromatase inhibitors. The first evidence regarding the possible benefit of extending adjuvant endocrine therapy beyond 5 years of tamoxifen was based on the results of the MA.17 trial, where patients were randomized to receive or not receive letrozole following the completion of tamoxifen treatment. The main analysis indicated that women originally assigned to receive letrozole had a 32% reduction in the risk of relapse [3]. A subgroup analysis suggested that the benefit in terms of disease-free survival was greater in premenopausal women at the time of initial diagnosis than in postmenopausal patients [3]. More recently, the results of two important clinical trials that assessed the possible benefit of extending adjuvant tamoxifen up to 10 years instead of stopping it after 5 years became available [4,5]. The ATLAS trial included a total of 12,894 patients: 2482 (19%) were younger than 45 years at diagnosis and 1058 (8%) were known to be premenopausal at the