Case Report: a three-stage treatment strategy combining immunotherapy with chemoradiotherapy for locally advanced esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC), a common malignant tumor with high incidence and mortality in China, remains challenging to treat, especially in advanced stages. Traditional definitive chemoradiotherapy (dCRT) has been the standard care for unresectable locally advanced ESCC but has shown limited long-term efficacy. Recent advances in immune checkpoint inhibitors (ICIs) have opened new avenues for enhancing treatment outcomes. This case report details a 62-year-old male with upper thoracic LA-ESCC (cT3N1M0) who underwent a comprehensive three-stage treatment strategy combining immunotherapy with dCRT. The treatment phases included induction chemotherapy with immunotherapy, followed by radical chemoradiotherapy, and subsequent immunotherapy maintenance. The patient demonstrated significant tumor regression, achieving a complete response and a progression-free survival of 27 months by December 13, 2025. During the treatment, immune-related adverse events (irAEs), including immune diabetes, emerged but were managed effectively through timely intervention and monitoring. This report underscores the potential of immunotherapy combined with dCRT to enhance survival and quality of life in patients with unresectable LA-ESCC. It also identifies key areas for further research: optimizing treatment protocols, improving management of immune-related adverse events, and identifying predictive biomarkers for treatment response. Large-scale prospective clinical trials will be essential to refine these strategies and advance precision therapy in this population.