Camrelizumab combined with apatinib plus irinotecan as a second-line treatment in advanced or metastatic esophageal squamous cell carcinoma patients.

Background: Camrelizumab (CAM) combined with apatinib plus chemotherapy as a first-line treatment shows good efficacy in advanced or metastatic esophageal squamous cell carcinoma (ESCC) patients. This study aimed to explore the potential of CAM combined with apatinib plus irinotecan (IRT) as a second-line treatment in advanced or metastatic ESCC patients.

Methods: A total of 59 advanced or metastatic ESCC patients receiving CAM combined with apatinib plus IRT as second-line treatment were enrolled in this study between January 2020 and March 2024. The primary endpoint was progression-free survival (PFS), with secondary endpoints including overall survival (OS), the objective response rate (ORR), the disease control rate (DCR), and the assessment of toxicity. Concurrently, a model was constructed utilizing patients' clinical characteristics and radiomic features to predict the patients' prognoses.

Results: At the time of analysis, 58 patients were withdrawn due to disease progression (n = 9), death (n = 43), or lost to follow-up (n = 6), and 1 patient was ongoing. The ORR and DCR were 37.7% and 84.9%, respectively. The median PFS and OS were 6.3 (95% CI: 4.8-7.8) and 16.7 (95% CI: 13.5-19.9) months, respectively. The most common adverse events of any grade were leukopenia (52.5%), fatigue (25.4%), anemia (23.7%), thrombocytopenia (23.7%), neutropenia (22.0%), and hypoalbuminemia (22.0%). Most of the adverse events were grade I-II. The incidence of grade III-IV adverse events was 20.3%. Predictive models were established based on the outcomes of multivariate Cox analyses. The combined model had an excellent ability to predict the 1-year OS [AUC (95% CI): 0.979 (0.930-1.000)].

Conclusions: CAM combined with apatinib plus IRT as a second-line treatment exhibits acceptable efficacy and safety in advanced or metastatic ESCC patients. The model that combines clinical and radiomic features has the greatest ability to predict the survival of advanced or metastatic ESCC patients.