Wunderle M, et al. - In this prospective, single-arm, multicenter PreFace study, researchers evaluated 3,529 postmenopausal women with hormone receptor-positive early breast cancer (BC) to assess the relationships between epidemiological risk factors and immunohistochemical subtypes. They observed that the strongest correlation existed between molecular subtypes of BC and hormone replacement therapy (HRT) before the diagnosis of early BC. Study participants who had never taken HRT or had stopped taking it had luminal B-like BC and HER2-positive BC. They noted no relations with factors like age at diagnosis, body mass index, smoking status, age at menopause, number of deliveries, age at first delivery, breastfeeding history, and family history.