P1.232. Treatment Outcomes of Conversion Surgery for Advanced Esophageal Cancer Following ICI-Combined Chemotherapy

Abstract

Abstract Topic Esophageal Cancer: Surgical Treatment of Esophageal Cancer – long term outcomes Background Immune checkpoint inhibitor (ICI)-based combination chemotherapy for advanced esophageal cancer demonstrates high response rates, enabling conversion surgery in some cases. However, reports on the safety and prognosis of cases undergoing resection after ICI-combined chemotherapy remain limited. We retrospectively reviewed the treatment outcomes of nine Stage IV esophageal cancer patients who underwent conversion surgery after ICI-combined chemotherapy. Methods This study included 9 patients who underwent conversion surgery at our hospital between April 2023 and April 2025 following combination chemotherapy with immune checkpoint inhibitors (Nivolumab + CF or Pembrolizumab + CF). Background factors, pathological grade, best treatment response, OS/PFS, site of recurrence, and postoperative recurrence interval were retrospectively evaluated. Results Preoperative stage IVA/IVB: 3/6 patients. Average postoperative hospital stay: 19 days. Grade 3 or higher pneumonia was observed in one case. Pathological response (Grade) was: 1a: 4 cases, 1b: 1 case, 2: 3 cases, 3: 2 cases. R0 resection was achieved in 7 cases. Median OS was 20.1 months, median PFS was 11.9 months. The median survival by pathological grade was OS: Grade 1a: 25.3 months, Grade 1b: 11.0 months, Grade 2: 16.8 months, Grade 3: 22.2 months. PFS was Grade 1a: 15.7 months, Grade 1b: 3.5 months, Grade 2: 11.3 months, Grade 3: 18 months. Recurrence was observed in 8 of 9 cases. The median postoperative recurrence interval was 180 days (range: 43–502 days), and the median postoperative survival time was 440 days (range: 215–711 days). Conclusion In a review of 9 cases of advanced esophageal cancer undergoing conversion surgery after ICI-combined chemotherapy, R0 resection was achieved in 7 cases, but postoperative recurrence was high at 8 cases. There was no correlation between pathological treatment response (Grade) and recurrence-free period; some Grade 3 cases remained recurrence-free, suggesting potential for long-term survival. The median overall survival (OS) was 20 months, and the median postoperative survival was 440 days, suggesting a certain degree of long-term survival can be expected. There are no unified standards for postoperative adjuvant therapy or treatment upon recurrence, necessitating further investigation.