A b d o m i n a l I m a g i n g • C o m m e n t a r yWe don't invent our natures. They're issued to us along with our lungs, our pancreas, and everything else.-Michael Mann, The Silence of the Lambs [1] ystic pancreatic lesions are commonly detected, reflecting both better imaging resolution and the increased utilization of abdominal radiologic studies in our aging population [2]. They are most frequently incidental findings that are not related to the reason or reasons for imaging the patients in whom they are discovered [3][4][5][6][7]. The radiologic and clinical challenges are to differentiate the more common pseudocysts from mucinous pancreatic neoplasms, including mucinous cystic neoplasm and intraductal papillary mucinous neoplasm, and from serous cystadenomas and to determine the benign or malignant nature of the lesion and its potential resectability. These challenges have a reward in that the preinvasive stages of intraductal papillary mucinous neoplasm and mucinous cystic neoplasm are macroscopic and detectable on cross-sectional imaging.Cystic degeneration of pancreatic adenocarcinoma and of solid and cystic pseudopapillary tumors, which have a variety of names, is less commonly encountered, and there are other rare cystic tumors of the pancreas, including cystic islet cell tumors and lymphoepithelial cysts, among others. Pseudocyst can most likely be inferred by a history of acute or chronic pancreatitis; alcoholism; complicated gallstone disease; and findings on pancreatic imaging including parenchymal calcifications, visualization of pancreatic duct side branches, and atrophy.Intraductal papillary mucinous neoplasms are found most commonly in elderly men and occur most often in the pancreatic head, whereas mucinous cystic neoplasms are usually noted in the pancreatic tail of middle-aged women [8]. Unfortunately, the more recent literature has shown that the age and sex of the patient with a cystic pancreatic lesion and the location of a cystic pancreatic lesion are not particularly reliable indicators for the accurate prospective diagnosis of an individual lesion [4].Characterization of cystic pancreatic lesions has been problematic since their initial modern classification by two pathologists at the Armed Forces Institute of Pathology in 1978, Compagno and Oertel [9,10]. Cystic pancreatic lesions continue to be problematic for the radiologist and clinician alike for numerous reasons. They have been the subject of several excellent recent reviews from the Massachusetts General Hospital [11][12][13][14]. The article by Visser and colleagues [15], from the Departments of Surgery, Radiology, and Epidemiology and Biostatistics at the University of California at San Francisco, in this issue of the AJR, highlights these troubling problems and provides an opportunity to examine the current status of imaging and clinical evaluation and management of these lesions. Numerous strides have been made in the fields of radiology, gastroenterology, abdominal surgery, and pathology in the diagnosis and management o...
