Precursor Lesions of Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer death. Although the treatment modalities are improving, the prognosis of PDAC continues to be poor. Therefore, early detection of PDAC or its precursor lesions may be the best way to improve patient survival. PDACs have several different precursor lesions, including pancreatic intraepithelial neoplasias (PanINs), intraductal papillary mucinous neoplasms (IPMNs), intraductal tubulopapillary neoplasms (ITPNs), intraductal oncocytic papillary neoplasms (IOPNs), and mucinous cystic neoplasms (MCNs). PanINs cannot be identified using imaging modalities, while the other lesions are radiologically detectable. These precursor lesions are categorized based on structural and cytological atypia as low-grade and high-grade lesions. We discuss recent updates regarding histopathological and molecular pathological overviews of PDAC precursor lesions. Better understanding of such lesions may contribute to earlier detection of PDAC or its precursor lesions and improve PDAC patient survival.