['Neoadjuvant chemoradiotherapy (nCRT) followed by esophagectomy confers a survival benefit on patients with esophageal cancer. However, nCRT might be less meaningful for poor responders. Thus, being able to predict responses would help ensure the selection of optimal therapy.', 'We reviewed data from 123 patients with esophageal squamous cell carcinoma (ESCC) who underwent nCRT that comprised concurrent radiation (40 Gy) and chemotherapy followed by esophagectomy. We assessed associations between clinical and blood data obtained before starting nCRT and the pathologic response.', 'We compared good (Japan Esophageal Society response evaluation criteria grades 3/2; n = 89, 72.4%) and poor (grades 1/0; n = 34, 27.6%) responders. Performance status (p = 0.02), hemoglobin level (p = 0.005), and platelet counts (p = 0.03) were statistically significant pretherapeutic factors for a response to nCRT. Multivariable analysis subsequently selected the hemoglobin level (odds ratio 1.52; 95% confidence interval 1.08-2.15; p = 0.02) as the sole independent predictor. Receiver operating characteristic curves showed that the optimal cutoff for pretherapeutic hemoglobin was 13 g/dl for predicting a response. We found that 48.8 and 17.1% of patients with hemoglobin level ≤13 and >13 g/dl, respectively, were poor responders (p = 0.0002), with 5-year overall survival rates of 40.9 and 58.9%, respectively (p = 0.048).'] Does hemoglobin level influence tumor response and survival after neoadjuvant chemoradiotherapy for esophageal squamous cell carcinoma?