Detection of Pancreatic Carcinoma and Liver Metastases with Gadoxetic Acid-enhanced MR Imaging: Comparison with Contrast-enhanced Multi-Detector Row CT

Purpose: To intraindividually compare gadoxetic acid-enhanced magnetic resonance (MR) imaging with contrast material-enhanced multi-detector row computed tomography (CT) in detection of pancreatic carcinoma and liver metastases. Materials and Methods: The ethics committee approved this retrospective study with waiver of informed consent. This study included 100 patients (53 men, 47 women; mean age, 67.8 years) consisting of 54 patients with pathologically confirmed pancreatic carcinoma (mean size, 33 mm) and 46 without a pancreatic lesion. Sixty-two liver metastases (mean size, 10 mm) in 15 patients with pancreatic carcinoma were diagnosed at pathologic examination or multimodality assessment. Three readers blinded to the final diagnosis interpreted all MR (precontrast T1- and T2-weighted and gadoxetic acid-enhanced dynamic and hepatocyte phase MR images) and tetraphasic dynamic contrast-enhanced CT images and graded the presence (or absence) of pancreatic carcinoma and liver metastasis on patient-by-patient and lesion-by-lesion bases. Receiver operating characteristic analysis, McNemar test, and Fisher test were performed to compare the diagnostic performance of CT and MR imaging. Results: No significant differences were observed between CT and MR images in depiction of pancreatic carcinoma. However, MR imaging had greater sensitivity in depicting liver metastasis than did CT for two of the three readers in the MR imaging-versus-CT analysis (85% vs 69%, P = .046) and for all three readers in the lesion-by-lesion analysis (92%-94% vs 74%-76%, P = .030-.044). Conclusion: Gadoxetic acid-enhanced MR imaging was equivalent to dynamic contrast-enhanced CT in depicting pancreatic carcinoma and had better sensitivity for depicting liver metastases, suggesting the usefulness of gadoxetic acid-enhanced MR imaging for evaluation of patients with pancreatic carcinoma. (C) RSNA, 2011