Purpose To investigate the prognostic impact of body size changes during the first postoperative year in breast cancer. Methods A cohort of 1,317 primary breast cancer patients included in Sweden (2002–2014) underwent body size measurements at the preoperative and 1-year visits ( n = 1,178). Landmark survival analyses were used to investigate how postoperative weight gain or loss (> 5%) or change in waist–hip ratio (WHR) categ...