Colorectal neuroendocrine carcinoma: A case report and review of the literature

BACKGROUND Colorectal neuroendocrine carcinoma (NEC) is a rare tumor that demonstrates aggressive growth pattern with ingrowth into the tract, metastasis to the other organs, and invasion to the surrounding organs; these clinical characteristics result in poor prognosis. Surgical resection appears as an effective approach; however, because it is difficult to accurately diagnose NEC during the early stage and owing to its aggressive growth pattern, development of a reliable standard chemotherapy regimen and management strategies are essential.