Pathological complete response and successful conversion surgery after nivolumab therapy for stage IV oesophagogastric junction cancer

Background: Multimodality treatment including immune check point inhibitors is required for stage IV oesophagogastric junction cancer (OGJC). Case Report: A 69-year-old man, was diagnosed with advanced OGJC and para-aortic lymph node metastasis (T3N+M1, stage IV), which upon biopsy, was shown to be an adenocarcinoma. After eight courses of nivolumab as third-line chemotherapy, the primary tumour and enlarged regional and para-aortic lymph nodes shrunk markedly, while tumour markers decreased within normal ranges. We performed a minimally invasive Ivor-Lewis oesophagectomy with completion of an abdominal D2 and transhiatal lower mediastinal lymph node dissection. Pathological findings revealed a complete response for the primary tumour and a regional lymph node metastasis. A biopsy of the previous sample revealed microsatellite instability-negativity, Epstein-Barr virus-negativity, and programmed cell death-1-ligand combined positive score of 2. He was followed up for 3 months without recurrence. Conclusion: Nivolumab may induce pathological complete response for stage IV OGJC even in cases negative for microsatellite instability and Epstein-Barr virus, besides the programmed cell death-1-ligand combined positive score of <5.