Laparoscopic-assisted distal gastrectomy and central pancreatectomy for gastric and perigastric lymph node metastases and pancreatic invasion from melanoma: a case report

BACKGROUND: In melanoma, completely resectable metastases are surgically resected to expect to prolong relapse-free survival and overall survival. However, distant metastases of melanoma are rarely indicated for surgery because multiple metastases are often observed at diagnosis. We report a case of a man in his 50s who underwent laparoscopic-assisted distal gastrectomy and central pancreatectomy for gastric metastases, lymph node metastases, and pancreatic invasion that could be completely resected. CASE PRESENTATION: A 50-year-old man was diagnosed with malignant melanoma of the left parietal region. After diagnosis, tumor resection and left cervical lymph node dissection were performed, and interferon-β treatment was added as adjuvant therapy. Seventeen months after adjuvant therapy, metastasis of stomach and abdominal lymph nodes from melanoma was diagnosed. And the pancreatic invasion of lymph nodes was suspected. Laparoscopic-assisted distal gastrectomy and the central pancreatectomy were performed because pancreatic invasion of melanoma was intraoperatively found. After 9 months of relapse-free survival, abdominal recurrence was observed. Nivolumab and ipilimumab were administered, and recurrent lesions are currently controlled. The patient has survived more than 3 years since metastasis resection. CONCLUSION: In conclusion, laparoscopic-assisted distal gastrectomy and the central pancreatectomy were performed for gastric and perigastric lymph node metastases and pancreatic invasion due to malignant melanoma, and the negative surgical margin was achieved. Although patient selection is required, the central pancreatectomy was a good indication for maintaining exocrine and endocrine function. The development of immune checkpoint inhibitors and molecular-targeted agents may increase gastrointestinal surgery for metastatic melanoma in the future.