Nimotuzumab Combined With Concurrent Curative Radiotherapy and S-1 in 75 Years and Older Patients With Stage II-IVB Esophageal Squamous Cell Carcinoma: A Phase II Study.

Concurrent chemoradiotherapy is the standard treatment for inoperable, locally advanced esophageal cancer. However, older patients often have reduced tolerance to radiotherapy and concurrent intravenous chemotherapy due to declining physical function and multiple comorbidities. This prospective, single-center, phase II study assessed the efficacy and safety of nimotuzumab, an epidermal growth factor receptor antagonist, combined with concurrent radiotherapy and S-1 in patients 75 years and older. A total of 56 patients were enrolled, with the primary endpoint being progression-free survival (PFS), while secondary endpoints included overall survival (OS), objective response rate, disease control rate, treatment-related adverse events, nutritional indicators, and quality of life (QOL). Most nutritional indicators remained stable after treatment. As of June 2024, the median follow-up duration was 24.1 months (8.8-34.1). Eleven patients achieved complete response, 39 achieved partial response, five had stable disease, and one experienced progressive disease. The median PFS was 25.3 months (95% CI, 16.5-34.1), while the median OS was 28.2 months (95% CI, 24.1-32.3). Most adverse events were grade 1-2 (85.7%). Among survivors, 45.5% reported high satisfaction with their QOL, and 84.8% did not experience weight loss. This combination therapy demonstrated promising efficacy and safety, suggesting it may be a viable treatment option for this patient population.