Comparisons of dynamic infusion and delayed computed tomography, intraoperative ultrasound, and palpation in the diagnosis of liver metastases.

The purpose of this study was to determine whether delayed computed tomography (DCT) of the liver would more accurately detect hepatic malignancy when compared with bolus contrast-enhanced dynamic computed tomography (BCDCT). Fifty-one patients who required operation for intra-abdominal malignancy (92% with colorectal cancers) underwent preoperative BCDCT followed by DCT. At operation, palpation and intraoperative ultrasound (IOUS) examination of the liver were performed for localization and biopsy of tumor nodules. The standard for diagnosis was defined for this study as the combined results of IOUS, palpation, and biopsy. The sensitivities of BCDCT and DCT for hepatic metastases were 50% and 54%, respectively, with a corresponding specificity of 72% for each. DCT demonstrated no significant improvement over BCDCT in the detection of individual hepatic lesions. The sensitivity of palpation for the detection of metastases was 82%, equal to that of IOUS. Both palpation and IOUS were significantly superior to BCDCT or DCT in excluding false-positive and false-negative results (p < 0.001). IOUS failed to identify surface lesions less than 1.0 cm in diameter (sensitivity: 40%). Conversely, palpation was limited in the detection of subsurface tumors less than 1.0 cm in diameter (sensitivity: 33%). Combined IOUS and palpation were significantly more accurate in the detection of hepatic metastases than any single modality that was evaluated (p < 0.001).