Three courses of treatment increase the efficacy of neoadjuvant immunochemotherapy in patients with local advanced ESCC without increasing TRAEs compared with two courses of treatment

Abstract Background: Immune checkpoint (ICI) monotherapy and neoadjuvant immunochemotherapy has shown promising results in esophageal carcinoma. However, it is still unclear whether more courses in immunochemotherapy are 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: This was a secondary analysis of the ChiCTR2000029807 clinical trial. Locally advanced ESCC patients have to receive three courses of camrelizumab (200mg every three weeks) plus nab-paclitaxel (260 mg/m2 every three weeks) and capecitabine (1250 mg/m2 every three weeks) before undergoing surgery. Patients received safety assessment, CT, and endoscopy (with endoscopic ultrasonography and mucosal biopsy) efficacy assessments before and in the second and third courses of treatment. We used the second and third courses' CT and endoscopic assessment results 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-PD-1 therapy and radical surgical resection. All Forty-three patients received safety assessments and CT efficacy assessments. Sixteen patients did not undergo an endoscopy examination during the second course of treatment because of esophageal stenosis or refused the endoscopy examination. The toxicity of the third course of immunochemotherapy was mild and well tolerated without increased treatment-related adverse events (TRAEs) and mortality compared with the second course of treatment. In terms of efficacy, an additional course of treatment after the second course of treatment was effective, which continued to increase the CT and endoscopy T downstaging rates by 16.3% and 25.9%, N downstaging rates by 7.0% and 11.1%, and ORR by 13.6 and 22.0%, respectively. Conclusions: No matter downstaging or ORR, three courses of immunochemotherapy appear to be superior to two courses of treatment without increasing TRAEs. (www.chictr.org.cn number, ChiCTR2000029807)