Pancreatic and Peripancreatic Diseases Mimicking Primary Pancreatic Neoplasia

Abstract

A variety of anatomic variants and pathologic conditions in and around the pancreas may simulate primary pancreatic neoplasia at routine abdominal cross-sectional imaging. An ambiguous lesion whose appearance suggests a pancreatic origin requires a broad differential diagnosis that can subsequently be narrowed on the basis of both clinical history and features at optimal computed tomography (CT) and magnetic resonance (MR) imaging. Pancreas-specific multidetector CT and MR imaging techniques with thin collimation, multiplanar and multiphasic scans, and newly introduced curved planar reformation may help avoid potential diagnostic pitfalls. These techniques can help identify and characterize a mass in multiple viewing planes, thereby helping distinguish a true pancreatic neoplasm from peripancreatic adenopathy or from a tumor of the adjacent duodenum or small bowel. They can also help determine the cause of a tumor. It is important that the radiologist be familiar with the wide spectrum of anatomic variants and disease entities that can mimic primary pancreatic neoplasia in order to initiate the appropriate lesion-specific work-up and treatment and avoid unnecessary tests or procedures, including surgery.

Recent advances in choledochal cysts

“…Curved planar reformation (CPR) has proved to be a practical and widely used tool for the visualization of curved tubular structures in the human body. CPR may be helpful in depicting pancreatic and common bile ducts [65,66].…”

Magnetic resonance imaging findings of the mass‐forming type of autoimmune pancreatitis: Comparison with pancreatic adenocarcinoma

“…Although there are five main criteria for the AIP diagnosis, composed of the typical imaging findings, laboratory data, histology, the presence of other organ involvement, and the response to corticosteroid therapy, imaging plays a critical role in the diagnosis of AIP because of many proposed diagnostic criteria (15, 16). To date, most of the literature reports have concentrated on the endoscopic retrograde cholangiopancreatography (ERCP) and CT features of AIP (10, 16–22). The main findings that are diagnostic or highly suggestive of AIP on CT include a diffusely enlarged pancreas with featureless borders and delayed enhancement with or without a capsule‐like rim (5).…”

Isolated pancreatic heamorrhage in association with anticoagulation

“…The periampullary region is anatomically and physiologically complex, thus focal haemorrhage involving any of its structures can mimic the presentation of a neoplasm. Although at times challenging, they can be differentiated by various imaging modalities from their enhancement pattern, signal characteristics or metabolic activities [2,3]. What is unique in these two cases is that the patients had isolated focal pancreatic parenchymal haemorrhage in the absence of a neoplasm, pancreatitis or trauma.…”