[A Case of Advanced Gastric Cancer with Cervical Lymph Node Metastasis Responding to SOX+Nivolumab and Treated with Conversion Surgery].

A66-year-old man was diagnosed with gastric cancer with cervical lymph node metastasis(cT4aN1pM1, Stage ⅣB). He received chemotherapy with 4 courses of SOX+nivolumab. The primary gastric tumor had shrunk significantly and the cervical lymph nodes could no longer be identified. The therapeutic effect was judged as partial response(PR). We decided to performed conversion surgery. Total gastrectomy and left cervical lymphadenectomy were performed. Histological examination revealed a Grade 2a response in the primary tumor, with no viable tumor cells found in the cervical lymph nodes (ypT4aN1M0, Stage ⅢA). Postoperative adjuvant chemotherapy with nivolumab was initiated. Approximately 16 months after surgery, no apparent recurrence has been observed.