Curable Resection in Gastric and Lymph Node Metastases From Melanoma

We herein report a rare case of gastric and regional lymph node metastasis of cutaneous malignant melanoma that underwent curative resection. The patient, a 68-year-old man, was first diagnosed as having cutaneous malignant melanoma of the right forearm in 2005. He had extensive skin excision and axillary lymph node dissection and had undergone adjuvant chemotherapy. Six years after the primary surgery, gastrointestinal endoscopy revealed gastric metastasis of a malignant melanoma. As there was no other metastasis found, laparoscopic-assisted distal gastrectomy with lymph node dissection was performed. Microscopic findings showed diffuse melanin granule growth invading the muscularis propria of the stomach. Micrometastases of the lymph nodes were observed that were not detected by preoperative examination. Seventeen months have passed without recurrence. We conclude that regional lymph node dissection should be performed with gastrectomy whenever distant metastases are not observed, because there is a possibility of micrometastases, which cannot be detected preoperatively.