Colonic Neuroendocrine Carcinoma with Adenocarcinoma and Squamous Cell Carcinoma: Report of a Case

Neuroendocrine carcinoma (NEC) of the colon is a rare entity; however, this type of tumor is known for its aggressive progression and poor prognosis(1). We describe a case of a 63-year-old Japanese female with a NEC of the cecum who received laparoscopic assisted right-hemicolectomy in this report. Histopathological findings of the resected specimen revealed a low-grade atypical gland (adenoma or well-differentiated adenocarcinorma) in the mucosa, but most of the tumor was composed of small cells with a high nuclear/cytoplasmic ratio mainly under the submucosa and had small foci of squamous cell carcinoma. On immunohistochemical staining, these atypical cells showed positive reactions for CD56, and the lesion was diagnosed as NEC of the colon. Chemotherapy with 5-fluorouracil / leucovorin was performed, but multiple liver metastases were detected 5 months after the operation. Hepatic arterial infusion chemotherapy with irinotecan plus 5-fluorouracil was given as second-line treatment, the patient survived for 18 months after the operation. We reported a case of colonic NEC with adenocarcinoma and squamous cell carcinoma, because of it is interest when considering the differentiation of neoplastic colonic NE cells. Abbreviations: neuroendocrine (NE), neuroendocrine carcinoma (NEC), endoscopic mucosal resection (EMR)