Stage IV gastric cancer successfully treated by multidisciplinary therapy including chemotherapy, immunotherapy, and surgery: a case report

BACKGROUND: The prognosis of stage IV gastric cancer (GC) still remains unfavorable. Multidisciplinary approaches should therefore be considered to improve the survival of patients with stage IV GC. We report here a case of primary GC with potentially unresectable metastasis, successfully treated by a multidisciplinary approach including chemotherapy, immunotherapy, and surgery. CASE PRESENTATION: A 74-year-old man presented with multiple left neck masses. Abdominal computed tomography showed a thickened gastric wall and multiple lymphadenopathies including left supraclavicular lymph node. Gastroenterological endoscopy revealed tumor lesions in the gastric cardia. Tumor biopsy indicated a pathological diagnosis of poorly differentiated adenocarcinoma. Open left cervical lymph node biopsy showed histological features identical with the gastric tumor, indicating left clavicle lymph node metastasis of GC. After 2 years of chemo-immunotherapy with S-1/CDDP, paclitaxel, and cytokine-activated killer cells, lesions other than the stomach lesion had regressed to undetectable on imaging studies. The patient then underwent laparoscopy-assisted total gastrectomy with Roux-en-Y reconstruction followed by adjuvant chemo-immunotherapy with paclitaxel and S-1 for 1 year, and immunotherapy with tumor lysate-pulsed dendritic cell-activated killer cells for 5 years. The patient remained well after 5 years and 6 months of follow-up, with no signs of recurrence. CONCLUSION: Therapeutic combinations including immunotherapy may thus allow surgery to be performed in patients previously considered unsuitable for surgical intervention, potentially leading to a clinical cure, as in the current case.