Background: EC is associated with significant MN. Resultant weight loss (WL) can be further exacerbated by toxicity of nCRT. We evaluated the association of surrogates of MN and T during nCRT for EC. Methods: A retrospective analysis of EC patients (pts) treated with nCRT as part of tri-modality therapy between 2002-2014 was performed. The following pre and post-CRT factors were assessed: presence of jejunostomy tube (J-tube), weight change (gain, loss of < 5%, 5-10%, ≥ 10%) and albumin change (decrease by < 0.5 or ≥ 0.5). We recorded rates of chemotherapy (ctx) dose reduction/interruption (DRI), hospitalizations (H), grade 3/4 T (G3+T), any grade non-hematologic (NHT) or hematologic T (HT). Multivariate regression analyses (MVA) were used to determine associations between MN and T, adjusting for age, gender, smoking status, stage, CRT regimen, performance status, and co-morbidities. Results: 125 patients were identified. Median age was 63 (range 35-80). Pre-CRT body mass index ranged from 17-45 kg/m2, with 74% overweight or obese. Mean WL during nCRT was 10 lbs (5%). Increased WL was noted in pts who received cisplatin/5-FU as compared to other ctx (p < 0.001) or ≥ 50 Gy (p = 0.025). In MVA, increased NHT was noted in pts with ≥ 5% WL (p < 0.05) and more G3+T was noted in pts with ≥ 10% WL (p = 0.002). A decrease in albumin by ≥ 0.5 was associated with increased DRI (p = 0.043), NHT (p = 0.004), HT (p = 0.002), and G3+T (p = 0.004). Sixty-three pts (50%) had a J-tube prior to nCRT. Pts with a J-tube had reduced mean WL (8 lbs vs 13 lbs) during nCRT. No differences in T were noted based on J-tube status. No associations between MN and H rates were observed. Conclusions: Hypoalbuminemia and WL during nCRT were associated with multiple T endpoints. The presence of a prophylactic J-tube did not reduce T rates. Other methods to prevent MN and reduce T during nCRT should be studied.