Comparison of MRI and endoscopic ultrasound in the characterization of pancreatic cystic lesions.

OBJECTIVE: The purpose of this study was to compare the diagnostic performance of MRI and endoscopic ultrasound (EUS) for the characterization of cystic pancreatic lesions and prediction of malignancy.

MATERIALS AND METHODS: Fifty patients (24 women and 26 men; average age, 57 years) underwent both MRI and EUS. All pancreatic lesions (21 cystic and 29 solid lesions) were proven by histopathologic analysis. Two radiologists retrospectively examined MR images, and a single gastroenterologist reviewed EUS images. The MRI and EUS characterizations of morphologic features of the cystic lesions and predictions of malignancy were evaluated. The prediction of malignancy was done by receiver operating characteristic (ROC) curve analysis.

RESULTS: There was no difference between the ability of MRI and EUS to correctly classify lesions as cystic or solid (accuracy, 90-98% vs 88%; p > 0.05). There was no difference between the sensitivity of MRI and EUS for the characterization of septa (94.4% for MRI vs 77.8% for EUS), mural nodule (66.7-58.3% for MRI vs 58.3% for EUS), main pancreatic duct dilatation (92.9-85.7% for MRI vs 85.7% for EUS), and communication with main pancreatic duct (100% for MRI vs 88.9% for EUS). The area under ROC curve values for predicting malignancy showed no statistical significance (0.755-0.774 for MRI vs 0.769 for EUS; p > 0.894).

CONCLUSION: MRI and EUS are comparable in the characterization of cystic pancreatic lesions and prediction of malignancy.