['To assess the impact of baseline nutritional status on treatment response and survival in nonmetastatic patients with a locally advanced esophageal cancer (LAEC) treated with definitive chemoradiotherapy (CRT).', 'One hundred five patients with LAEC treated by definitive CRT were retrospectively included. The CRT regimen was based on an external radiotherapy (RT) delivered concomitantly to a cisplatin-based chemotherapy (CT). Patients were considered to have a complete response (CR) to CRT when no residual tumor was detected on CT scan and esophagoscopy performed 2 months after the end of CRT. Multivariate analysis of predictive factors of response to CRT and survival were performed using a logistic regression and a Cox model, respectively.', 'Mean value of baseline nutritional parameters was significantly different between nonresponder (N = 42) and responder (N = 63) patients to CRT (weight loss 10%vs 5.8%, P= 0.0047; serum albumin level 35 g/L vs 38.7 g/L, P= 0.0004; BMI 22.8 kg/m2vs 25.2 kg/m2, P= 0.01). In multivariate analysis, serum albumin level > 35 g/L was the only independent predictive factor of CR to CRT (P= 0.009). Independent prognostic factors of survival were BMI > 18 kg/m2 (P= 0.003), dysphagia Atkinson score <2 (P= 0.008), dose of RT > 50 Grays (Gy) (P < 0.0001) and CR to CRT (P < 0.0001).'] Is baseline nutritional status predictive of response to treatment and survival in patients treated by definitive chemoradiotherapy for a locally advanced esophageal cancer?