Real-World Study of Camrelizumab-based Regimen for Locally Advanced and Metastatic Esophageal Cancer

Background Camrelizumab is a PD-1 inhibitor independently developed in China, which has been approved for use in the treatment of esophageal cancer. However, its efficacy and safety data in clinical practice are still lacking. Objective This study is aimed at assessing the Camrelizumab-based regimens' safety and efficacy for locally advanced and metastatic esophageal cancer in the real world, and explore whether the reactive cutaneous capillary endothelial proliferation (RCCEP) could predict the efficacy of carrelizumab under different treatment modalities. Methods Cases of locally advanced and metastatic esophageal cancer treated with camrelizumab-based regimens in the Fourth Hospital of Hebei Medical University between 1 November 2019 and 31 May 2022 were retrospectively examined. Progression free survival (PFS), overall survival (OS), disease control rate (DCR), objective remission rate (ORR) and adverse events were evaluated. Using the Kaplan-Meier approach to compute the median and estimated 95% CI for PFS and OS. Comparing the survival function of patients in the RCCEP group and without RCCEP group. Results A total of 70 patients were included in the study. In all patients, the efficacy was evaluated as CR 11 (15.7%), PR 35 (50.0%), SD 17 (24.3%), PD 7 (10%), ORR 65.7% (46/70) and DCR 90.0% (63/70). In the 47 patients who receiving first-line to third-line treatment, the median PFS was 8.1 months (95%CI=6.46 to 9.74 months) and the 1-year PFS rate was 34.0%. The median OS was not reached, the 1-year OS rate of 76.3%. In the 23 patients who receiving neoadjuvant therapy, all patients achieved R0 resection, and 6 patients (26.1%) achieved pCR. In terms of safety, the most observed TRAEs included RCCEP (65.7%), nausea/vomiting (42.8%), anemia (37.1%), fatigue (37.1%) and alopecia (34.2%). The incidence of adverse reactions≥grade 3 was 21.4% (15/70), mainly including leukopenia (5.7%), neutropenia (5.7%) and thrombocytopenia (4.3%). Four patients developed immune related adverse reactions≥grade 3, including one case of grade 3 myocarditis, one case of grade 3 pneumonia, one case of grade 3 rash and one case of grade 4 nephritis. All patients were relieved after symptomatic or glucocorticoid treatment and no drug-related deaths occurred. RCCEP was associated with the efficacy of camrelizumab. The ORR (76.1% vs 45.8%, P=0.010) and DCR (97.8% vs 75.0%, P=0.009) of patients with RCCEP were higher than those without RCCEP. The median PFS (18 months vs 7.4 months, P=0.015) and OS (not reaching vs 15.7 months, P<0.001) of patients with RCCEP were significantly longer than those without RCCEP. Conclusion In the real world, camrelizumab-based regimens achieved good disease control and tolerance for treating locally advanced and metastatic esophageal carcinoma. In different treatment modalities, RCCEP could predicts the efficacy of camrelizumab.