Feigelson HS, Bodelon C, Powers JD, et al. - Whether and how body mass index (BMI) is related to the risk for developing second cancers among women with incident invasive breast cancer was assessed. Researchers analyzed a retrospective cohort of 6,481 patients, of whom 822 (12.7%) suffered a second cancer (mean follow-up was 88.0 months). Using medical records, BMI at the first cancer was obtained. Increasing BMI was found to be related to a statistically significant elevated risk of second cancers in this study population. ,For every 5 kg/m2 increase in BMI, the risk of any second cancer diagnosis increased by 7%; 13% for obesity-related cancers; 11% for a second breast cancer, and 15% for a second ER-positive breast cancer, as seen in multivariable models. The results call for effective prophylactic strategies.