A CASE OF SMALL CARCINOID TUMOR WITH REGIONAL LYMPH NODE METASTASIS

Abstract

A 64-year-old woman was admitted to the hospital because of diarrhea. Colonoscopic examination showed a sessile yellow lesion of the lower rectum. Histological examination of a biopsied specimen was diagnosed as rectal carcinoid tumor. We recommended endoscopic resection to the patient but she disapproved the therapy. We performed a low anterior resection. The resected specimen contained a small elevated lesion measuring 7×5mm. The tumor was limited within the submucosal layer, having submucosal vascular invasion and regional lymph node involvement. The small carcinoid tumor of the rectum with the diameter of less than 10mm and submucosal invasion associated with lymph node metastasis is rare. To the best of our knowledge, this is the 13th case reported in Japan. We consider that local resection is indicated for rectal carcinoid tumor less than 10mm in diameter, and radical operation with lymph node dissection is indicated if vascular invasion is present, even though muscle invasion is absent on histological examination.