RESUMO
Objective:To explore the pathological differences of surgically resected specimens of advanced esophageal squamous cell carcinoma (ESCC) to different neoadjuvant therapies (neoadjuvant radiochemotherapy and toripalimab combined with neoadjuvant radiochemotherapy).Methods:Thirty patients diagnosed with advanced ESCC who underwent surgical operation after neoadjuvant therapy in Jiangsu Cancer Hospital from October 2020 to September 2021 were included. Among them, 15 patients received neoadjuvant radiochemotherapy (radiochemotherapy group) and 15 patients were treated with toripalimab combined with radiochemotherapy (immunotherapy combined with radiochemotherapy group). Surgically resected specimens were collected. The histopathological features of primary esophageal lesions and the responses of involved lymph nodes were analyzed and compared between two groups.Results:The major pathological response (MPR) rate in the radiochemotherapy group was 10/15, and 14/15 in the immunotherapy combined with radiochemotherapy group ( P=0.17). The pathological complete response (pCR) rate of the primary lesions in the radiochemotherapy group was 7/15, and 10/15 in the immunotherapy combined with radiochemotherapy group ( P=0.46). In the radiochemotherapy group, the incidence rate of tertiary lymphoid structure (TLS) was 7/15, and 12/15 in the immunotherapy combined with radiochemotherapy group ( P=0.02). The incidence rate of necrosis in the radiochemotherapy group was 6/15, and 1/15 in the immunotherapy combined with radiochemotherapy group ( P=0.03). In addition, the incidence rate of foam cell infiltration in the radiochemotherapy group was 6/15, and 13/15 in the immunotherapy combined with radiochemotherapy group ( P=0.01). Furthermore, the pCR rate of involved lymph nodes in the radiochemotherapy group was 7/33, and 11/12 in the immunotherapy combined with radiochemotherapy group ( P<0.001). Conclusion:Compared with the radiochemotherapy group, the incidence of TLS and foam cell infiltration is higher, the incidence of necrosis is lower and clinical efficacy of involved lymph nodes is higher in the immunotherapy combined with radiochemotherapy group, prompting that toripalimab combined with neoadjuvant radiochemotherapy exert higher synergistic immune effect.
