![Sample our Sports and Leisure journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/5949/TOC-Subject-Sample-2021-Sports-Leisure.jpg"})
ABSTRACT
Night work has been associated with risk of breast cancer but this association needs to be confirmed. Because breast cancer is an etiologically heterogeneous disease, we explored the association of night work with breast cancer subtypes defined by tumor status (positive of negative) for estrogen-receptor (ER), progesterone-receptor (PR) and human epidermal growth factor-receptor 2 (HER2). Using the data from a case–control study in France including 975 cases and 1317 controls, we found that the odds ratios for ER+, PR+ or HER2+ breast cancers subtypes were significantly elevated, while no association with night shift work was observed for ER, PR or HER2-negative tumors. After stratification by menopausal status, the associations of night work with receptor-positive breast tumor subtypes were clearly seen in premenopausal women (odds ratios 2.04, 1.98 and 2.80, respectively) but did not appear in postmenopausal women. This study provides evidence that working at night may increase risk of ER, PR and HER2-positive subtypes of breast cancer particularly among premenopausal women.
Declaration of interest
Grant sponsors: Agence nationale de sécurité sanitaire de l’alimentation, de l’environnement et du travail (ANSES); Agence Nationale de la Recherche (ANR); Fondation de France; Institut National du Cancer (INCA); Ligue contre le Cancer.
