Neoadjuvant chemoradiotherapy treatment represents the standard approach for resectable locally advanced esophageal squamous cell carcinoma. The incidence of pulmonary infection and other perioperative complications were higher in patients who received esophagectomy and neoadjuvant chemoradiotherapy than those without neoadjuvant treatment and surgery patients. However,reliable clinical data can quantify the damage degree of immunologic function caused by chemotherapy and radiotherapy is still unknown. This project regards the level of lymphocyte and immunocyte in peripheral blood as a quantitative index to reflect the dynamic change of the immunologic function of patients with locally advanced esophageal squamous cell carcinoma after neoadjuvant chemoradiotherapy treatment. Meanwhile,the investigators will also investigate the relationship between the level of lymphocyte and immunocyte in peripheral blood and the response rate of neoadjuvant therapy.