Characterization of cystic tumors of the pancreas: CT accuracy

Purpose: The purpose of this work was to evaluate the capabilities of CT to accurately characterize cystic tumors of the pancreas. Method: Two observers retrospectively evaluated the CT exams of 100 cystic masses of the pancreas, with pathological confirmation. The two observers, blinded about clinical information and the final diagnosis, tried to catego rize the lesions according to well established morphologic features. Statis tical analysis was performed to measure the agreement between each radiolog ist and the consensus diagnosis and to evaluate the usefulness of certain C T findings in differentiating one type of cystic pancreatic neoplasm from a nother, Results: Serous cystadenoma was better diagnosed by CT [Youden misclassific ation index (Ymi) = 0.72] than mucinous cystic tumor (Ymi = 0.44) and solid pseudopapillary tumor (cystic variant) (Ymi = 0.47). Conclusion: As patients with previous history of pancreatitis were excluded from the study, CT findings allowed correct characterization of only 60% o f cystic pancreatic masses. Among the remaining 40%, 15-20% of the wrong di agnoses could not be corrected by means of CT, given the patterns shown by the tumors. In 20-25% of the cases, a nonspecific diagnosis of cystic mass was made.