[A Case of Rectal Neuroendocrine Carcinoma Treated with Multidisciplinary Therapy but with a Poor Prognosis].

A 70-year-old man presented to our hospital with weight loss. A colonoscopy revealed advanced cancer in the lower rectum. Computed tomography showed a tumor larger than 5 cm in the lower rectum with metastasis to the right lateral lymph node. The patient was diagnosed with advanced locally rectal cancer, and chemoradiotherapy(35 Gy plus S-1)was added after 6 courses of mFOLFOX6, and laparoscopic abdominal perineal resection and right lateral lymph nodes dissection were performed. Histopathological examination revealed endocrine cell carcinoma(pT3[A], pN0, M0, pStage Ⅱa). Four months after the operation, recurrence was found in the pelvis, lymph nodes, and lungs, and he died 9 months after the operation. Neuroendocrine carcinoma is relatively rare, so the further accumulation of cases and establishment of treatment methods are desired.