BackgroundClinical trials have demonstrated methods to minimize the risk of breast cancer-related lymphedema while preserving regional control. We sought to determine the percent lifetime-risk of breast cancer-related lymphedema that surgeons and radiation oncologists discuss with patients before axillary interventions. MethodsA nationwide survey of surgeons and radiation oncologists was performed from July to August 2020. Participants were asked to identify what number they discuss with patients when estimating the percent lifetime-risk of breast cancer-related lymphedema after different axillary interventions. ResultsSix hundred and eighty surgeons and 324 radiation oncologists responded (14% response rate). While the estimated rate after sentinel lymph node biopsy was clinically similar between surgeons and radiation oncologists, statistically surgeons quoted a higher percent lifetime-risk (5.7% vs 5.0%, P = .03).Surgeons estimated significantly higher rates of breast cancer-related lymphedema compared with radiation oncologists (P < .001) for axillary lymph node dissection (21.8% vs 17.5%), sentinel lymph node biopsy with regional nodal irradiation (14.1% vs 11.2%), and axillary lymph node dissection with regional nodal irradiation (34.8% vs 26.2%). ConclusionThere is variability in the estimated rates of breast cancer-related lymphedema providers discuss with patients. These findings highlight the need for physician education on the current evidence of percent lifetime-risk of breast cancer-related lymphedema to provide patients with accurate estimates before axillary interventions.