The management of cystic lesions of the pancreas.

The number of patients being identified as having asymptomatic small cysts of the pancreas is increasing. Most cystic neoplasms are SCAs, IPMNs, or MCNs. SCAs should be considered benign and in the absence of symptoms can be safely followed radiographically. Currently, most patients who present with mucinous cysts should undergo resection, because many of these patients have in situ or invasive carcinoma. The presence of a solid component seems to be associated with malignancy in patients who have mucinous cysts, and cyst size seems to be associated with malignancy in patients who have MCNs and branch duct IPMNs. Many institutions now are reporting a selective approach to resection in patients who have cystic lesions of the pancreas. Routine resection of all pancreatic cysts currently is impractical; given the large numbers of patients being identified with lesions smaller than 2 cm, this approach would result in a mortality rate that is much higher than the rate of malignancy. Most studies that have advocated a selective approach have reported the radiographic characteristics of a solid component, cyst size, and symptoms to be associated with treatment recommendations. The authors believe that radiographic follow-up is warranted in any patient for whom the assumed risk of malignancy is less than the risk of mortality from resection (no solid component, < 3 cm, asymptomatic). Most patients who have incidentally discovered cysts smaller than 3 cm in diameter and without a solid component can be safely followed radiographically. In the young patient who has a small mucinous tumor, additional factors to be considered are the likelihood of progression to malignancy and patient anxiety about radiographic follow-up. No data are available for the former. Efforts should be made to improve the ability to distinguish histopathologic subtypes without resection. The current challenges are to improve the sensitivity and specificity for the identification of mucinous subtype, to characterize better the progression of IPMN and mucinous cystic tumors, and to develop better methods for identifying the presence of in situ or invasive disease in these patients. Continued improvements in cross-sectional imaging and endoscopic techniques and further investigation into markers in the serum and cyst fluid should allow better identification of mucinous subtypes.