Subtyping of IPMN

Abstract

Intraductal papillary mucinous neoplasms (IPMNs) characteristically consist of mucin-filled dilated ducts lined with neoplastic cells forming papillae with a diverse range of morphologies and varying grades of atypia. Based on morphological characteristics and immunohistochemical reaction against mucin proteins, IPMNs are classified into four distinct subtypes: gastric, intestinal, pancreatobiliary, and oncocytic. In this chapter, histomorphological criteria and techniques of immunohistochemical staining and its evaluation for subtyping IPMNs are described.