Intraductal papillary mucinous neoplasms of the pancreas: is the puzzle solved?

Intraductal papillary mucinous neoplasms (IPMN) are drawing more attention and being detected more frequently. This review focuses on current understanding of the management of IPMN, regarding morphological classification, subclassification by cell lineage features, molecular abnormalities, radiological and imaging evaluation, progression to cancer, incidence and risk factors for malignancy, risk of distinct pancreatic adenocarcinoma and extrapancreatic malignancies, treatment strategy, and types of surgical resection. In particular, missing links in solving the IPMN puzzles are described with regard to differential diagnosis, role of cyst fluid analysis, multifocal IPMN, histological evaluation of the surgical specimen, observation without resection, follow up of patients after resection, role of adjuvant therapy for invasive carcinoma, screening for other neoplasms in patients with IPMN on follow up, prognostic factors influencing long-term outcomes, and role of endoscopic therapy.