LAUSR

Background: surgery to treat breast cancer (BC) is associated with upper limb (UL) lymphedema, which in some cases may become permanent. It is uncertain whether lymphedema results from injury to either lymphatic or blood vessels, or to both. Methods and Results: a cohort of 200 BC patients was examined 1, 3, 6, 12, and 24 months after surgery. Axillary and brachial blood vessels were evaluated using Doppler Ultrasound, and patients had their UL examined for lymphedema at each visit. Patients who developed lymphedema 24 months after surgery presented with higher mean flow velocity (MFV) and end diastolic velocity (EDV) in both axillary (MFV = 13.57 vs. 10.7 cm/s, p = 0.02; EDV = 5.62 vs. 3.47 cm/s; p = 0.004) and brachial (MFV = 11.44 vs. 8.74 cm/s; p = 0.03; EDV = 5.08 vs. 3.04; p = 0.04) arteries as early as 1 month after surgery. Similar associations were found 3, 6, and 12 months after surgery. Early abnormalities of the resistive and pulsatility indexes were also significantly associated with persistent lymphedema. EDV measured 1 month after surgery had the best performance to detect patients who will later develop long-term lymphedema, (sensitivity = 73.7%; specificity = 71.2%; negative predictive value = 57.6%). Conclusion: vascular abnormalities precede and are possible causal factors for UL lymphedema in BC patients.