RESUMEN
Objective:To investigate the efficacy of immune checkpoint inhibitor maintenance therapy after radical radiotherapy and chemotherapy for stage Ⅲ-ⅣA esophageal squamous cell carcinoma (ESCC) in the real world.Methods:The clinical data of 65 patients with stage Ⅲ-ⅣA ESCC treated by radical radiotherapy and chemotherapy from January 1, 2018 to December 31, 2022 in Hefei Cancer Hospital, Chinese Academy of Sciences were retrospectively analyzed. According to whether to undergo immune checkpoint inhibitor maintenance therapy after radical radiotherapy and chemotherapy, the patients were divided into a control group ( n=29) and an immune maintenance therapy group ( n=36) . The objective response rate (ORR) , progression-free survival (PFS) , and overall survival (OS) between the two groups were compared. Kaplan-Meier method was used to draw the survival curve accompanied with log-rank test. Cox regression model was used to conduct both univariate and multivariate analyses. Results:The ORR was 34.5% (10/29) in the control group and 61.1% (22/36) in the immune maintenance therapy group, with a statistically significant difference ( χ2=4.56, P=0.032) . The median PFS of control group and immune maintenance therapy group were 7.2 and 17.9 months, respectively, with a statistically significant difference ( χ2=7.86, P=0.005) . The median OS was 14.1 and 27.8 months, respectively, with a statistically significant difference ( χ2=5.40, P=0.020) . Univariate analysis showed that, objective response ( HR=0.09, 95% CI: 0.03-0.28, P<0.001) and immune maintenance therapy ( HR=0.38, 95% CI: 0.17-0.88, P=0.024) were the influential factors of OS in ESCC patients treaded by radical chemoradiotherapy in stage Ⅲ-ⅣA. Multivariate analysis showed that, objective response ( HR=0.09, 95% CI: 0.03-0.29, P<0.001) and immune maintenance therapy ( HR=0.40, 95% CI: 0.17-0.92, P=0.032) were the independent influencing factors for OS in ESCC patients treaded by radical chemoracial therapy in stage Ⅲ-ⅣA. The incidence of adverse reactions was 22.22% (8/36) in the immune maintenance therapy group and 10.34% (3/29) in the control group, with no statistically significant difference ( χ2=1.61, P=0.204) . All the adverse reactions were grade 1-2, and the symptoms were relieved after symptomatic treatment. Conclusion:Maintenance therapy with immune checkpoint inhibitors after radical chemoradiotherapy of stage Ⅲ-ⅣA ESCC can significantly improve the prognosis of patients with good safety.