Claims study of 1,877 patients for 2 years after the start of cancer treatment. 10% of patients developed lymphedema with ALND and chemotherapy associated with development. Higher medical costs associated with BCRL diagnosis ($23, 167 vs. $14,877) with higher rates of cellulitis/lymphangitis noted. Although the use of claims data may underestimate the true incidence of lymphedema, women with BCRL had a greater risk of infections and incurred higher medical costs. The substantial costs documented here suggest that further efforts should be made to elucidate reduction and prevention strategies for BCRL. Open access: Yes View