Retrospective study of continued immunotherapy in patients with advanced esophageal squamous cell carcinoma after progression on first-line immunotherapy combination chemotherapy.

e16025 Background: Immunotherapy combined with chemotherapy has become the standard first-line treatment for advanced esophageal squamous cell carcinoma. However, the disease progression pattern after first-line immunotherapy resistance and the second-line treatment options are not fully understood. This retrospective study was designed to explore the efficacy of continued immunotherapy in advanced esophageal squamous cell carcinoma patients after progression on first-line immunotherapy combination chemotherapy. Methods: We retrospectively analyzed the efficacy of second-line continued immunotherapy in patients with stage IV esophageal squamous cell carcinoma who experienced disease progression after first-line immunotherapy at Huai 'an First People's Hospital from July 2020 to December 2023. The main outcome were progression-free survival (PFS), 3-and 6-month PFS rates, objective response rate (ORR), disease control rate(DCR)and overall survival (OS). Results: A total of 30 eligible patients were included. Median age was 67 years, 20 (66.7%) patients were male. 14 patients achieved partial response (PR), 8 stable disease (SD), illustrating an ORR of 46.7% and a DCR of 73.3%. Median PFS was 3.85 months. In the second-line treatment regimen, 21 (70%) were immunotherapy combined chemotherapy, and the others were immunomonotherapy or combined anti-angiogenic drugs. Conclusions: The current retrospective data shows that a considerable number of patients still could benefit from second-line immunotherapy after the progress of first-line immunotherapy in patients with advanced ESCC. This result brings new hope for the increasingly large population of immune resistance esophageal cancer patients. [Table: see text]