Hereditary and Sporadic Pancreatic Ductal Adenocarcinoma: Current Update on Genetics and Imaging

Pancreatic ductal adenocarcinoma (PDAC) is a genetically heterogeneous, biologically aggressive malignancy with a uniformly poor prognosis. While most pancreatic cancers arise sporadically, a small subset of PDACs develop in patients with hereditary and familial predisposition. Detailed studies of the rare hereditary syndromes have led to identification of specific genetic abnormalities that contribute to malignancy. For example, germline mutations involving BRCA1, BRCA2, PRSS1, and mismatch repair genes predispose patients to PDAC. While patients with Lynch syndrome develop a rare "medullary" variant of adenocarcinoma, intraductal papillary mucinous tumors are observed in patients with McCune-Albright syndrome. It is now well established that PDACs originate via a multistep progression from microscopic and macroscopic precursors due to cumulative genetic abnormalities. Improved knowledge of tumor genetics and oncologic pathways has contributed to a better understanding of tumor biology with attendant implications on diagnosis, management, and prognosis. In this article, the genetic landscape of PDAC and its precursors will be described, the hereditary syndromes that predispose to PDAC will be reviewed, and the current role of imaging in screening and staging assessment, as well as the potential role of molecular tumor-targeted imaging for evaluation of patients with PDAC and its precursors, will be discussed. (C)RSNA, 2020