© 2012 The Korean Society of Pathologists/The Korean Society for Cytopathology pISSN 1738-1843

In 1727, Schilz first reported the example of a heterotopic pancreas and defined it as tissue histologically similar to normal pancreas but located somewhere other than its usual location, and without anatomic or vascular connection to the pancreas it-self.1 A heterotopic pancreas is usually asymptomatic. The fre-quent sites of heterotopia are the stomach and duodenum, but a jejunal location is less common.1 Most pathologic changes of pancreas can occur in a heterotopic pancreas, but malignant transformation is rare. Furthermore, we have not found any re-port regarding an adenocarcinoma associated with intraductal papillary mucinous neoplasm (IPMN) in a heterotopic pancreas. In this case report, we describe a rare case of an adenocarcinoma arising in a jejunal heterotopic pancreas associated with IPMN, which was clinically misdiagnosed as perforated sigmoid colon cancer