Extrahepatic abdominal imaging in patients with malignancy: comparison of MR imaging and helical CT, with subsequent surgical correlation.

Abstract

To compare state-of-the-art magnetic resonance (MR) imaging with single-phase helical computed tomography (CT) in abdominal screening for extrahepatic disease in patients with proved malignancy. Fifty-seven patients with known malignancy underwent abdominal contrast material-enhanced helical CT and MR imaging from 1994 through 1997. Prospective interpretations of CT scans and MR images were used to assess each modality's sensitivity in depicting malignant extrahepatic tumor at 17 anatomic sites. Imaging findings were compared with surgical results in all patients. Helical CT depicted 101 (66%) of 154 surgically confirmed extrahepatic tumor sites; MR imaging depicted 139 (90%) (P < .001). MR imaging depicted tumor in more patients at 11 of the 17 anatomic sites; at six sites, MR imaging and helical CT were equivalent. MR imaging showed significantly greater depiction of extrahepatic tumor for the peritoneum (P < .05), bowel (P < .01), and mesentery (P < .05). False-negative interpretations would have altered patient care had the extrahepatic tumor remained undetected in 13 patients for helical CT and in six patients for MR imaging. State-of-the-art MR imaging can be used for effective abdominal screening for extrahepatic tumor in patients with malignancy. Compared with single-phase helical CT, MR imaging depicted more sites of extrahepatic tumor and was particularly advantageous for the peritoneum, mesentery, and bowel.