We performed a multi-institutional analysis to evaluate the ability of bioimpedance spectroscopy (BIS) to capture the impact of lymphedema treatment compared with observation alone in the management of breast cancer related lymphedema (BCRL). We utilized a retrospective review of 50 patients with breast cancer who were evaluated with BIS at baseline and following loco-regional treatment. An analysis was performed comparing changes in L-Dex scores for those patients undergoing treatment for BCRL (n=13) versus those not undergoing intervention (n=37). A second (subset) analysis was also performed on all patients with elevated L-Dex scores compared to baseline prior to undergoing loco-regional treatment (n=32). When comparing the cohort treated for BCRL to those not treated, L-Dex scores were significantly reduced (-4.3 v. 0.1, p=0.005) in the period following intervention (for treated patients). For the subset of patients with elevated L-Dex scores postoperation, the change in L-Dex score following BCRL treatment was significantly reduced (-5.8 v. 0.1, p=0.001) compared with the group observed that had elevated postsurgical L-Dex scores. In this analysis, BIS was able to detect early onset lymphedema and subsequently significant changes (reductions) in L-Dex scores directly related to intervention for BCRL compared with observation alone.