Are more courses of immunochemotherapy beneficial for the short-term outcome of locally advanced esophageal squamous cell carcinoma?

BACKGROUND: Immune checkpoint inhibitor (ICI) monotherapy and neoadjuvant immunochemotherapy have shown promising results in esophageal carcinoma. However, it is still unclear whether more courses of immunochemotherapy are therapeutically better. We aimed to investigate the safety and efficacy of three courses of neoadjuvant treatment for patients with locally advanced esophageal squamous cell carcinoma (ESCC). METHODS: Patients with locally advanced ESCC received three courses of camrelizumab plus nab-paclitaxel and capecitabine before undergoing surgery. Additionally, patients received safety, computed tomography (CT), and endoscopy (with endoscopic ultrasonography and mucosal biopsy) assessments before and in the second and third courses of treatment. We used the CT and endoscopic assessment results from the second and third courses for comparison. RESULTS: From May 2020 to December 2021, 47 patients were enrolled at Sun Yat-sen University Cancer Center. In our study, 43 patients completed three courses of preoperative chemotherapy combined with anti-Programmed cell death-1 (PD-1) therapy and radical surgical resection. The toxicity of the third course of immunochemotherapy was mild and well tolerated without increased treatment-related adverse events (TRAEs) and mortality compared with that of the second course of treatment. In terms of efficacy, an additional course of treatment after the second course of treatment was effective, with increased CT and endoscopy T (clinical T stage) downstaging rates by 16.3% and 25.9%, N (clincial N stage) downstaging rates by 7.0% and 11.1%, and objective response rates (ORRs) by 13.6% and 22.0%, respectively. CONCLUSIONS: Regardless of downstaging or ORR, three courses of immunochemotherapy appear to be superior to two courses of treatment without increasing TRAEs.