A Case of Neuroendocrine Tumor of the Small Intestine Presented with an Abdominal Mass due to Lymph Node Metastasis

• Published in: Nihon Rinsho Geka Gakkai Zasshi (Journal of Japan Surgical Association) Vol. 77; no. 5; pp. 1110 - 1115
• Main Authors: HIRANO, Kosuke, SUGAMATA, Yoshitake, OKUYAMA, Takashi, ONO, Yuko, BAN, Shinichi, SAMESHIMA, Shinichi, NOIE, Tamaki, OYA, Masatoshi
• Format: Journal Article
• Language: Japanese
• Published: Japan Surgical Association 2016
• Subjects: NET; neuroendocrine tumor; small intestine
• ISSN: 1345-2843; 1882-5133
• DOI: 10.3919/jjsa.77.1110

A 76-year-old woman was introduced to our hospital for detailed inspection and treatment for an abdominal mass detected incidentally by a CT scan for a medical checkup. A lobulated share mass, 4cm in size and enhanced by a contrast medium, was detected inside of the mesentery of small inetestine on an abdominal CT scan in our hospital. Abdominal MRI revealed high signal intensity of the mass on diffusion weighted image. Laparotomy was carried out with a preoperative diagnosis of malignant lymphoma or GIST. The mass detected by CT and MRI was an enlarged mesenteric lymph node belonging to the small bowel. A constricted tumor was also identified in the small bowel. Small bowel resection with lymphadenectomy was carried out. The tumors were diagnosed as a neuroendocrine tumor of the small bowel and its lymph node metastasis. The histopathological diagnosis was neuroendocrine tumor (G2), pT3 (SS), pN1, ly2, v3 and Stage IIIb. When we encounter a mass in the mesentery on imagings like in our case, not only malignant lymphoma or GIST but also lymph node metastasis of neuroendocrine tumor should be included in the differential diagnosis. Radical operation including lymph node dissection appears desirable if distant metastasis is absent.