Adenocarcinoma of the colon with neuroendocrine features and secretory diarrhea.

We report the case of a 63-yr-old man who had severe secretory diarrhea associated with colonic adenocarcinoma, with a prominent signet ring cell component and numerous endocrine cells as demonstrated by positive chromogranin-A staining. Improvement in the secretory diarrhea by the somatostatin analog Sandostatin suggested that the diarrhea was related to a functional neuroendocrine tumor within the colonic tumor, the first case to be reported in the literature.