Hepatic metastases from colorectal cancer: Preoperative detection and assessment of resectability with helical CT

PURPOSE: To prospectively evaluate helical computed tomography (CT) in the preoperative detection of hepatic metastases and assessment of resectabilit y with surgical, intraoperative ultrasonographic (US), and histopathologic correlation. MATERIALS AND METHODS: Between October 1995 and December 1998, preoperative staging with helical CT (5-mm collimation; reconstruction interval, 5 mm) was performed in 157 patients with hepatic metastases. Iodinated contrast m aterial 5 was injected intravenously (160-170 mL; rate, 2.5-3.0 mL/sec); ac quisition began at 60-70 seconds. Four radiologists prospectively assessed the metastatic involvement of the liver by indicating the number and locati on of the lesions; resection was indicated in 113 patients (119 instances). Helical CT findings were correlated with pathologic and surgical findings an a lesion-by-lesion basis. RESULTS: Intraoperative US, palpation, and histopathologic examination reve aled 290 liver metastases; helical CT correctly depicted 247. Helical CT re sults were the following: overall detection rate, 85.1% (95% CI: 80.8%, 89. 3%); positive predictive value, 96.1% (95% CI: 92.9%, 98.1%); and false-pos itive rate, 3.9% (10 of 257 findings; 95% CI: 1.9%, 7.1%). False-positive f indings were related to hemangioen-dothelioma, hemangioma, hepatic peliosis , biliary adenoma, centrilobar; hemorrhage, biliary hamartoma, periportal f ibrosis, and normal liver parenchyma. Curative resection was performed in 1 12 instances with a resectability rate of 94.1%. Four-year patient survival rate was 58.6%. CONCLUSION: Helical CT is a noninvasive, reliable, and accurate technique f or imaging the liver and should be considered as the standard preoperative work-up of hepatic metastases from colorectal cancer.