Uptodate in the assessment and management of intraductal papillary mucinous neoplasms of the pancreas.

Intraductal Papillary Mucinous Neoplasms (IPMNs) are the most common cystic tumors of the pancreas and are considered premalignant lesions. IPMNs are characterized by the papillary growth of the ductal epithelium with rich mucin production, which is responsible for cystic segmental or diffuse dilatation of the main pancreatic duct (MPD) and/or its branches. According to the different involvement of pancreatic duct system, IPMNs are divided into main duct type (MD-IPMN), branch duct type (BD-IPMN), and mixed type (MT-IPMN). IPMNs may be incidentally discovered in asymptomatic patients, particularly in those with BD-IPMNs, when imaging studies are performed for unrelated indications. The increase in their frequency may reflect the combined effects of new diagnostic techniques, the improvement of radiologic exams and progress in the recognition of the pathology. MD-IPMNs present a higher risk of malignant progression than BD-IPMNs; as a consequence, all the guidelines strictly suggest the need of surgery for MD- and MT- IPMNs with MPD > 10 mm, while the management of BD-IPMNs is still controversial and depends on several cysts and patients features. The choice between non-operative and surgical management depends on the distinction between benign and invasive IPMN forms, assessment of malignancy risk, patient's wellness and its preferences. This manuscript revises the different guidelines for the management of IPMNs that have been published in different world countries: the international (Sendai 2006 and Fukuoka 2012), the 2013 European, the 2014 Italian, and finally the 2015 American guidelines. In summary, this review will integrate the recent insights in the combination of diagnostic techniques, such as Magnetic Resonance Imaging (MRI) and endoscopic ultrasound (EUS), pathology classification, and management of IPMNs.