P1.116. Comparison Between Nivolumab + Ipilimumab, FOLFOX, and Nivolumab + FOLFOX Therapy as First-Line Therapy for Cisplatin-Unfit Advanced Esophageal Squamous Cell Carcinoma

Topic Esophageal Cancer: Non-Surgical Treatment of Esophageal Cancer Background Nivolumab plus platinum-based chemotherapy and nivolumab plus ipilimumab (Nivo+Ipi) therapy are standard first-line treatments for advanced esophageal squamous cell carcinoma (ESCC). However, patients with renal or cardiac dysfunction and elderly patients might be unfit for cisplatin-containing regimens. Therefore, leucovorin, 5-FU, and oxaliplatin (FOLFOX), Nivo+Ipi, and nivolumab plus FOLFOX (Nivo+FOLFOX) therapy might be alternative options for cisplatin-unfit population. Methods This retrospective study included cisplatin-unfit patients with histologically confirmed advanced ESCC treated with Nivo+Ipi, FOLFOX, or Nivo+FOLFOX in our hospital from March 2021 to July 2025 for the first-line treatment. Effectiveness was evaluated by objective response rate (ORR) assessed by the RECIST ver.1.1, progression-free survival (PFS), and overall survival (OS). To evaluate safety, adverse events were assessed by CTCAE ver. 5.0. Results Fifty patients were included (median age, 75 years; performance status 0/1/≥2, 20/70/10%). Eighteen (36%), 18 (36%), and 14 (28%) patients received Nivo+Ipi, FOLFOX, and Nivo+FOLFOX therapy, respectively. Median follow-up time was 12.4 months. PFS was significantly longer with Nivo+Ipi than with FOLFOX (median 8.5 vs. 3.2 months; HR 0.40, 95% CI 0.17–0.93, p = 0.028), whereas there was no significant difference in OS (median NR vs. 13.3 months; HR 0.48, 95% CI 0.18–1.27, p = 0.13). Nivo+FOLFOX showed significant improvements in PFS (median 6.5 vs. 3.2 months; HR 0.42 95% CI 0.18–0.99, p = 0.041) and ORR (64% vs. 28%, p = 0.039) compared with FOLFOX. The most common any grade adverse events were rash in Nivo+Ipi (n = 3, 17%) and neutropenia in FOLFOX (n = 5, 28%) and Nivo+FOLFOX (n = 6, 43%). Conclusion Nivo+Ipi and Nivo+FOLFOX may show improved effectiveness compared with FOLFOX alone and appear to be generally well-tolerated in patients with cisplatin-unfit advanced ESCC.