Detection of liver metastases from colorectal carcinoma: is there a place for routine computed tomography arteriography?

BACKGROUND A prospective evaluation of the liver by preoperative ultrasonography, conventional computed tomography (CT), and continuous CT angiography (CCTA) was performed in 60 patients with primary or secondary colorectal carcinoma. METHODS The standards of reference were palpation of the liver and intraoperative ultrasonography. The imaging techniques were assessed independently of each other. RESULTS In 37 patients 105 liver metastases were identified; 23 patients had no metastases. CCTA and a high sensitivity of 94% (99 lesions identified) in contrast to ultrasonography (48%) and conventional CT (52%). The superiority of CCTA was also manifest in lesions less than 1 cm in diameter. However, the high sensitivity was accompanied by a high false-positive rate, particularly because of variations in the perfusion of normal liver parenchyma. Overall, CCTA had the highest accuracy (74%) compared with ultrasonography and CT (both 57%). The data indicate that preoperative ultrasonography and conventional CT have low sensitivity in the detection of liver metastases. CONCLUSIONS Although CCTA seems to be superior to other preoperative imaging techniques, the too low specificity will hamper its routine application in patients with hepatic metastases from colorectal carcinoma.