Esophageal cancer is a high - incidence cancer type in China, characterized by high incidence, high mortality, and low survival rates. Over 90% of esophageal cancer cases in China are squamous cell carcinoma, while in Western countries, approximately 80% are adenocarcinomas. Current international guidelines, including those of the NCCN and CSCO, are not entirely suitable for the diagnosis and treatment of esophageal cancer in the Chinese context. In recent years, although the 5 - year survival rate for esophageal cancer has improved, significant challenges remain, such as severe side effects during chemoradiotherapy and targeted - immunotherapy, decreased patient tolerance and quality of life, and even interruption of treatment. To leverage the synergistic role of traditional Chinese medicine (TCM) in the treatment of major diseases, this study, which builds on previous research, is founded on the theory of "reinforcing healthy qi to strengthen the body, removing toxins, and resolving stasis." It aims to conduct a multicenter, randomized, controlled clinical trial of the TCM formula Yishen Qutong Granules, designed to reinforce healthy qi to strengthen the body and remove toxins, in combination with neoadjuvant concurrent therapy for locally advanced esophageal squamous cell carcinoma. The study will enroll 268 patients (1:1 ratio) with locally advanced esophageal squamous cell carcinoma (cTNM stage III - IVa) who are expected to undergo neoadjuvant concurrent therapy and are potentially resectable. On the basis of conventional Western medical treatment, the treatment group will be administered the patented TCM formula Yishen Qutong Granules orally, while the control group will receive a Yishen Qutong Simulated Granules orally. The primary outcome measure will be the clinical benefit rate (CBR, CBR = CR + PR + SD), with secondary outcomes including pathological response rate (mPR), R0 resection rate, and TCM syndrome symptom score. The study aims to establish an objective evaluation system for the efficacy and safety of combined treatment based on the integration of disease and syndrome differentiation. It will also elucidate the mechanisms underlying the therapeutic effects of Yishen Qutong Granules.