Comparison of CT, MRI and CT during arterial portography in the detection of malignant hepatic lesions.

Background/aims: A prospective study was performed to compare the sensitivities of computed tomography, magnetic resonance imaging and CTAP (CT during arterial portography) in the detection of focal malignant hepatic lesions.
Methodology: Twenty-eight (28) patients with primary and secondary hepatic malignant tumors were evaluated. All of these patients underwent hepatic resection and a lesion-to-lesion imaging-pathological analysis was performed.
Results: The overall sensitivities were 53% for CT, 66% for MRI sequences and 88% for CTAP. For lesions smaller than 1 cm the sensitivities were 6% for CT, 17% for MRI and 72% for CTAP. The combination of CTAP and MRI yielded an overall detection rate of 93%. The difference between the sensitivity of CTAP and that of the other two imaging techniques was statistically significant (P < 0.04) according to the McNemar test. CTAP demonstrated four false-positive lesions, two of which were correctly characterized by MRI and one by CT. In 6 patients (21.4%) the surgical plan was modified after CTAP.
Conclusions: We conclude that, CTAP has the highest sensitivity and should be part of the preoperative examination. In some instances, the addition of MR imaging must be considered a helpful adjuvant. Both techniques should be considered complementary in the preoperative diagnostic algorithm.