Body size and composition and risk of postmenopausal breast cancer

Abstract

Background: Studies of postmenopausal breast cancer have reported positive associations with body size and composition but it is uncertain whether these are due to non-adipose, adipose mass, or central adiposity, and whether they are limited to subgroups defined by age or tumor characteristics. Methods: In a prospective cohort study of women ages 27 to 75, body measurements were taken directly; fat mass and fat-free mass being estimated by bioelectrical impedance analysis, and central adiposity by waist circumference. Among 13,598 women followed on average for 9.1 years, 357 invasive breast cancers were ascertained via the population cancer registry. Data were obtained on estrogen receptor a..