Efficacy and safety of neoadjuvant chemotherapy and immunotherapy in locally resectable advanced esophageal squamous cell carcinoma

Background: Esophageal squamous cell cancer (ESCC) patients with the potentially resectable disease most would experience relapse after surgery. Immunotherapy has been reported to improve the prognosis of advanced esophageal cancer and may be a new strategy to prevent this urgent condition's recurrence. We first evaluated the efficacy and safety of neoadjuvant chemotherapy combined with immunotherapy in patients with resectable ESCC. Methods: All patients with resectable locally advanced ESCC (clinical stage III-IVB). Received at least 1 cycle of neoadjuvant chemotherapy combined with immunotherapy (NACI), and the interval between each cycle and the operation should be at least 3 weeks. All patients were treated with standard surgery. The tumor imaginations were obtained at baseline and within a week before surgery. The efficacy endpoint was the rate of major pathologic response (MPR, 10% viable tumor cells). Expression of immunohistochemicalrelated molecules was investigated in surgical samples. Results: A total of 38 patients with ESCC were included (36 males, median age 61 years), and most of them used Pembrolizumab (55.26%) and Camrelizumab (31.58%). We analyzed 19 patients and found that 13 patients (68.42%) achieved radiological partial response (PR) by CT images. R0 resection was performed in 35 patients (92.11%), and 10 patients (26.32%) developed postoperative complications. Through postoperative pathology, we found 13 (34.21%) patients had complete pathologic response (cPR), and 16 (42.11%) patients achieved MPR. We also found that none of the factors had a statistically significant impact on MPR. Still, the regression rate of Sum of lesion diameter (SLD) was significantly positively correlated with the pathological remission rate (P=0.012, r=0.565). Conclusion: The rate of MPR in ESCC patients reached 42.11%. The use of the NACI regimen did not increase the occurrence of complications in neoadjuvant treatment and operation, and the SLD regression rate has a certain guiding significance for the effect of immunotherapy.