Neuroendocrine Carcinomas of the Colon and Rectum

Abstract

Neuroendocrine carcinomas of the colon and rectum are uncommon, comprising less than 1 percent of colon and rectal cancers. Pathologically, these tumors are poorly differentiated carcinomas with distinctive cytoarchitectural features and are often immunoreactive for markers of neuroendocrine differentiation. The prognosis for high-grade neuroendocrine carcinomas is poor, as most patients have metastatic disease at the time of diagnosis.