The association between body mass index and immunohistochemical subtypes in breast cancer

Background:Body mass index (BMI) is defined as a poor prognostic factor in patients with breast cancer(BC). However, there are controversial results regarding the various effects of BMI on BC, hence the exactpathophysiology of the relation between obesity and BC is still under debate, and remains unclear. Thispaper aims to investigate the association between BMI at presentation and BC subtypes defined accordingto the immunohistochemical classification in both premenopausal and postmenopausal patients with BC.Patients and methods:This study is a retrospective and explorative analysis of the 3767 female BC pa-tients from a single center. All patients' BMI at the time of initial diagnosis and tumor demographics wererecorded. BMI was stratified into 3 groups as normal-weighted (BMI