Differential diagnosis between intraductal papillary-mucinous tumors and mucinous cystic tumors of the pancreas

Mucinous cystic tumors (MCTs) and intraductal papillary-mucinous tumors (IPMTs) are often confused with each other. However, clinicopathological studies have shown that these are two distinct entities. In this review clinicopathological differences and important features for differential diagnosis are presented. MCTs are cyst-forming tumors in the body or tail of the pancreas seen almost exclusively in females. IPMTs show distinct duct ectasia in the pancreatic head with male predominance. Histologically both tumors consist of mucin secreting tall columnar epithelium. MCTs are often accompanied by characteristic "ovarian-type stroma.'' Recent immunohistochemical and gene analysis have not demonstrated significant differences between two tumor types. These tumors should be clearly separated from ordinary ductal adenocarcinomas of the pancreas as they follow indolent course.