Resected Primary Gallbladder Neuroendocrine Tumor (G2) with Lymph Node Metastasis—A Case Report—

Abstract

A 64-year-old man was referred for evaluation of a 15 mm mass in the gallbladder neck detected on computed tomography. Laparoscopic cholecystectomy was performed for diagnostic and therapeutic purposes. Histopathological examination revealed a grade 2 neuroendocrine tumor (NET G2) with lymphatic invasion. Additional hepatic resection (subsegmentectomy of segments 4a and 5) and regional lymph node dissection were performed based on tumor grade and lymphatic involvement. Metastases containing components of adenocarcinoma were identified in the No. 8 lymph node. Esophagogastroduodenoscopy and colonoscopy revealed no evidence of primary adenocarcinoma. Therefore, the lymph node metastasis was diagnosed to be clinically attributed to the gallbladder NET G2. The patient postoperatively completed a an adjuvant chemotherapy with six-month oral S-1 administration. No recurrence was observed during these 36-month follow-up period. We report a rare case of a gallbladder NET G2 with lymph node metastasis. This case suggests the importance of curative resection with regional lymph-node dissection against more than 10 mm gallbladder NET G2 with lymphatic invasion.