Intraductal papillary mucinous tumors of the pancreas: spectrum of CT and MR findings with pathologic correlation.

The reports of intraductal papillary mucinous tumors (IPMT) of the pancreas are increasingly more frequent in the literature. The diagnosis by means of cross-sectional imaging of these tumors is not easy, especially in the early stages, when they can mimic an inflammatory disease of the pancreas. Prompt identification of the disease is nevertheless extremely important, especially in the case of tumors originating from the collateral branches, since its recognition can modify the management of the patient, in some cases obviating recourse to surgery.

CT features of malignant mucinous cystic tumors of the pancreas.

This study is aimed at evaluating which pre-operative findings at CT are prevailingly associated with histologically malignant appearance of mucinous cystic tumor (MCT) of the pancreas. The CT examinations of 52 female patients affected with pathologically proved MCT were retrospectively evaluated by two radiologists, blinded to the histopathological assessment of the biologic behavior (either benign or malignant). A multivariate logistic regression analysis was performed in order to identify the most important features associated with the malignant nature of MCT. Calcifications in the wall and/or in the septa, thick wall, and septations resulted in the most important features associated with malignancy. The simultaneous presence of all these radiological signs constitutes an almost "certain" marker of malignancy, being the risk equal to 0.95, whereas the simultaneous presence of at least two of them entails a risk of malignancy ranging from 0.56 to 0.74, according to the type of morphological features. On the other hand, the absence of the mentioned radiological features entails a negligible risk of malignancy (0.02). Mucinous cystic tumors characterized by multilocular macrocystic architecture, with thick wall and calcifications in the wall and/or the septa, present the highest risk of malignancy, and advocate prompt surgical intervention. When those signs are absent, the probability of malignancy is lower. In this case a non-operative management is possible.