Regional Nodal Irradiation Impact on Lymphedema, Surgical Outcomes, and Quality-of-Life Following Mastectomy,...

Radiation therapy following axillary lymph node dissection (ALND) is a key risk factor for lymphedema, with regional nodal irradiation (RNI) posing a higher risk. Immediate lymphatic reconstruction (ILR) with microsurgical lymphovenous anastomosis performed concurrently with ALND aims to prevent lymphedema, but its efficacy in the setting of RNI is unclear. This study compares lymphedema incidence, complications, and LYMPH-Q patient-reported outcomes (PROs) after ILR based on receipt of RNI.We retrospectively studied consecutive patients who underwent mastectomy and ALND with ILR between 2017 and 2024 at our institution. Patients receiving radiotherapy were categorized based on receipt of RNI, and outcomes were compared using multivariable regression, adjusting for patient and treatment factors.We identified 119 patients with a mean follow-up time of 25.0 ± 15.5 months, of whom 68.9% (n = 82) received RNI. Radiotherapy characteristics were comparable between the RNI and non-RNI cohorts, including 3D Conformal Radiotherapy use (95.1% vs. 88.2%, p = 0.945), mean chest wall radiation dose (5,006 ± 238 cGy vs. 5,054 ± 593 cGy, p = 0.656), and receipt of chest wall scar boosts (32.9% vs. 27.0%; p = 0.520). In adjusted analyses, RNI was not associated with higher odds of lymphedema (OR, 0.30; p = 0.429), surgical complications (OR: 1.94; p = 0.540), reoperation (OR: 1.11; p = 0.844) or worse LYMPH-Q symptoms (p = 0.823), function (p = 0.353), appearance (p = 0.362), or psychological well-being (p = 0.174) scales.RNI in the setting of ILR was not associated with increased surgical morbidity, lymphedema rates, or adverse patient-reported outcomes. While ILR may mitigate the expected morbidity of RNI, prospective studies are needed to establish its definitive value in this high-risk population.