Salvage camrelizumab plus apatinib for relapsed esophageal neuroendocrine carcinoma after esophagectomy: a case report and review of the literature.

The current evidence regarding immunotherapy plus targeted therapy in esophageal neuroendocrine carcinoma (NEC) is lacking. Camrelizumab is a programmed cell death protein 1 inhibitor. Apatinib is a selective tyrosine kinase inhibitor of vascular endothelial growth factor receptor-2. A 50-year-old female was initially diagnosed as primary esophageal NEC. Neoadjuvant chemotherapy and Ivor Lewis esophagectomy were performed (ypT3N0M0, stage Ⅱ). Twenty months after the surgery, an isolated mediastinal lymph node recurrence of NEC was recorded. The specimen revealed a positive expression of vascular endothelial growth factor and programmed cell death ligand 1. The diseased lymph node was slightly enlarged after two cycles of first-line paclitaxel liposome and S-1. Second-line apatinib and S-1 for 2 months also resulted in progressive disease. Subsequently, third-line camrelizumab plus apatinib was continued for 5 months. The patient demonstrated a progression-free status for more than 10 months following the combination therapy. Meanwhile, relevant studies of camrelizumab in gastric or esophageal cancer were briefly reviewed. Based on the current evidence, camrelizumab is a promising agent for esophageal cancer. More prospective trials are warranted before a definite recommendation could be drawn.