[Cystic tumors of the pancreas]

Cysts of the pancreas most often develop after chronic or acute inflammation of the pancreas. Cystic neoplasia of the pancreas have been increasingly recognized in clinical practice and 90% are represented by four types: serous microcystic (SCN), mucinous cystic (MCN), intraductal papillary-mucinous (IPMN) and solid pseudopapillary (SPN) neoplasia. IPMN is the most common form nowadays and main duct and branch duct types can be differentiated by morphology. This classification is of prognostic and therapeutic relevance. While main duct IPMNs have a high risk of malignant progression and resection is therefore recommended, branch duct IPMNs have a much lower risk of harboring malignancy. Small branch duct IPMNs (<2 cm) without symptoms or mural nodules can be managed by periodic surveillance. Recently, it has become clear that IPMN constitutes a heterogeneous group with at least four subtypes. Their stratification reveals that the various subtypes of IPMN have different biological properties with different prognostic implications, but the subclassification is usually not known prior to surgery. Moreover, even differentiation between inflammatory and neoplastic cysts can be challenging. Clear indications for resection are local complications (jaundice or gastric outlet obstruction), large and increasing tumors, symptoms or secretion of mucinous fluid from the papilla of Vater.