Islet tissue in the heterotopic pancreas.

Seventeen cases of heterotopic pancreas were studied with an immunocytochemical technique for detecting insulin and pancreatic polypeptide (PP)-containing cells. In all 16 cases that contained acinar tissue, there were fewer insulin cell areas, as well as fewer scattered PP cells. The numbers of PP cells in heterotopic pancreata were variable, from less than that of the PP-poor tail portion to more than that of the PP-rich uncinate process of control pancreata. Using PP cells as a marker for the anlage, heterotopic pancreata appear to derive from either PP-rich ventral or PP-poor dorsal anlagen.