Crippa et al. highlight the clinical and demographic differences between 168 patients with MCN and 159 with branch-duct IPMN (8). Patients with MCN were significantly younger (median 44.5 v. 66 yo, p=0.001) and almost exclusively women (95% v 57%, p=0.01) (8). MCN were most likely to be distal (97% v 25%, p =0.001) and were more likely to present with abdominal pain (62% v 45%, p=0.004) (8). IPMNs were also more likely to have a family history of pancreatic Inhibitors,research,lifescience,medical cancer (11% v 3.5%, p=0.01) and a history of other neoplasms (20 v 9%, p=0.006)

(8). Moreover, MCN are thought to be separate from the main pancreatic duct whereas side-branch IPMNs are connected to the main duct. Of course, distinguishing MCN from SB-IPMN is not always so straightforward as MCN are reported to be connected to the main duct in up to 20% of cases (9). At the University of Michigan, as

well as other expert centers, multidisciplinary care involving gastroenterologists, radiologists, and surgeons Inhibitors,research,lifescience,medical and oncologists have become a valuable addition Inhibitors,research,lifescience,medical to the care of patients with pancreatic cysts. Careful review of the patient’s history in the context of cross-sectional imaging, surgical risks, and an estimate of malignancy risk are taken into account with regard to clinical decisions. EUS and FNA also play an important role but are used selectively—it may Inhibitors,research,lifescience,medical serve as a confirmatory role (fluid analysis supporting mucinous etiology or benign nonmucinous etiology) and for high Belnacasan resolution imaging to rule out any solid component (See Fig 1). Figure 1 Clinical management of cystic lesion What the Al-Rashdan study fails to explore is the clinical context in which the cyst fluid analysis was drawn.

We do not know demographic information, imaging findings, or symptoms of the patient. This kind of information is likely to have played a stronger role than cyst fluid analysis in distinguishing the two etiologies and Inhibitors,research,lifescience,medical in driving the decision for resection. For example, multifocal cystic disease or an isolated lesion in the tail in a male is almost certainly IPMN and may not need resection. The critical question is whether any type cyst fluid analysis can add out incremental value for such patients—such as prediction of malignancy risk. This is particularly important in clinically equivocal cases, such as a woman with a solitary lesion in the body or tail whose lesion is not clearly distinct from the main duct. In its current state, CEA and amylase are clearly inadequate and better biomarkers clearly needed. There are a number of recent investigations to evaluate other cyst fluid biomarkers that may aid in the differentiation of mucinous cyst types. Prostaglandin (2) has been shown to have increased expression in pancreatic cancer tissue over normal pancreatic tissue (10) and may also distinguish between types of mucinous cysts.