[Histonet] rectal carcinoid tumor

[RSRICHMOND <@t> aol.com]

Diana McCaig asks: >>What special stain is recommended to confirm the 
diagnosis of carcinoid
tumor on a rectal polyp?<<

This is mostly an H & E diagnosis. The older special stains usually aren't 
positive in colorectal carcinoids. A synaptophysin immunostain would be most 
likely to give you the desired result, with colonic enterochromaffin 
(argentaffin) cells serving as an internal control. Chromogranin is somewhat less 
sensitive, and neuron specific enolase (NSE) is falling out of use. It's often useful 
to do a broad spectrum cytokeratin stain to make sure that the tissue is 
stainable.

Bob Richmond
Samurai Pathologist
Gastonia NC