Liver metastases from colorectal cancers: detection with CT during arterial portography

A total of 45 metastases to the liver from colorectal cancer were resected in 22 patients. The detectability of these lesions with the following modalities was determined: real-time ultrasound (US), computed tomography (CT), selective celiac arteriography (SCA), infusion hepatic angiography (IHA), CT during arterial portography (CTAP), and CT following intraarterial injection of iodized poppyseed oil (Lipiodol). The total detection rate (sensitivity) was 58% for US, 63% for CT, 27% for SCA, 50% for IHA, 84% for CTAP, and 38% for CT with iodized oil. Ten of 18 lesions less than 15 mm in largest diameter were demonstrated preoperatively by CTAP only. CTAP is useful in clarifying the locations of the lesions in the liver and should always be performed before liver metastases from colorectal cancer are resected.     

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 resectability 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 material was injected intravenously (160-170 mL; rate, 2.5-3.0 mL/sec); acquisition began at 60-70 seconds. Four radiologists prospectively assessed the metastatic involvement of the liver by indicating the number and location of the lesions; resection was indicated in 113 patients (119 instances). Helical CT findings were correlated with pathologic and surgical findings on a lesion-by-lesion basis. RESULTS: Intraoperative US, palpation, and histopathologic examination revealed 290 liver metastases; helical CT correctly depicted 247. Helical CT results 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-positive rate, 3.9% (10 of 257 findings; 95% CI: 1.9%, 7.1%). False-positive findings were related to hemangioendothelioma, hemangioma, hepatic peliosis, biliary adenoma, centrilobar hemorrhage, biliary hamartoma, periportal fibrosis, and normal liver parenchyma. Curative resection was performed in 112 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 for imaging the liver and should be considered as the standard preoperative work-up of hepatic metastases from colorectal cancer.     

Revealing hepatic metastases from colorectal cancer: value of combined helical CT during arterial portography and CT hepatic arteriography with a unified CT and angiography system

OBJECTIVE: The purpose of our study was to evaluate the use of combined helical CT during arterial portography and CT hepatic arteriography in the preoperative assessment of hepatic metastases from colorectal cancer using a unified CT and angiography system. MATERIALS AND METHODS: Fifty-four patients with hepatic metastases from colorectal cancer preoperatively underwent combined CT during arterial portography and CT hepatic arteriography using the unified CT and angiography system. Three radiologists independently and retrospectively reviewed the images of CT during arterial portography alone, CT hepatic arteriography alone, and combined CT during arterial portography and CT hepatic arteriography. Image review was conducted on a segment-by-segment basis; a total of 432 hepatic segments with (n = 103) 118 metastatic tumors ranging in size from 2 to 160 mm (mean, 25.8 mm) and without (n = 329) tumor were reviewed. RESULTS: Relative sensitivity of combined CT during arterial portography and CT hepatic arteriography (87%) was higher than that of CT during arterial portography alone (80%, p < 0.0005) and CT hepatic arteriography alone (83%, p < 0.005). Relative specificity of CT hepatic arteriography alone (95%, p < 0.0005) and combined CT during arterial portography and CT hepatic arteriography (96%, p < 0.0001) was higher than that of CT during arterial portography alone (91%). Diagnostic accuracy, determined by a receiver operating characteristic curve analysis, was greater with combined CT during arterial portography and CT hepatic arteriography than with CT during arterial portography alone (p < 0.05) or CT hepatic arteriography alone (p < 0.01). CONCLUSION: Using a unified CT and angiography system, we found that combined CT during arterial portography and CT hepatic arteriography significantly raised the detectability of hepatic metastases from colorectal cancer.     

Detection of liver metastases from colorectal cancer: comparison of intraoperative US and CT during arterial portography.

A prospective study was performed to compare the sensitivities of intraoperative ultrasound (US) and computed tomography during arterial portography (CTAP) in the depiction of hepatic metastases from colorectal cancer. Twenty-five patients with hepatic metastases from colorectal cancer were evaluated. All patients underwent partial hepatectomy, and 56 metastases were pathologically proved. Preoperatively, CTAP depicted 51 of the 56 metastases (91%). Intraoperative US depicted 54 of the 56 metastases (96%). Intraoperative US depicted three metastases (5%) that were not depicted with CTAP and two that were missed with palpation (3%). Furthermore, intraoperative US did not demonstrate any false-positive lesions. There was no statistically significant difference in sensitivity between the two techniques. The authors concluded that intraoperative US does not enable detection of more liver metastases from colorectal cancer when CTAP is considered as the preoperative standard of reference. Nevertheless, the results of the study suggest that intraoperative US and CTAP are complementary techniques, and the preoperative use of CTAP for determining the feasibility of hepatic resection cannot prevent the use of intraoperative US.     

Adenomatous hyperplasia with unusual imaging findings at combined helical CT hepatic arteriography and CT during arterial portography

We examined a patient with a hepatocellular carcinoma and multiple adenomatous hyperplasias in the cirrhotic liver. Helical CT hepatic arteriography (CTA) showed the adenomatous hyperplasias as areas of discrete hypoattenuation, and the combined CT during arterial portography (CTAP) showed corresponding areas of subtle hyperattenuation. Such imaging findings at combined CTA and CTAP were seen in only one patient in a series of more than 80 patients in whom we performed angiographically-assisted CT. We demonstrate these unusual imaging findings of adenomatous hyperplasia in the report.     

Intrahepatic portal venous variations: demonstration by helical CT during arterial portography

PURPOSE: We assessed the prevalence and types of intrahepatic portal venous variations by helical computed tomography performed with arterial portography (CTAP). METHODS: In 192 patients without evidence of vascular invasion or distortion, CTAP images were reviewed retrospectively to identify portal venous variations. RESULTS: Of the 192 patients examined, 10 (5.2%) had trifurcation, 5 (2.6%) had a right posterior segmental branch arising from the main portal vein, 5 (2.6%) had an absence of the horizontal segment of the left portal vein, and 1 (0.5%) had an absence of the left lateral segmental portal branch. Of the patients without a horizontal segment, two had a right-sided ligamentum teres associated with malposition of the gallbladder, while another had complete ramification of intrahepatic portal branches from an umbilical vein-like segment. In the patient missing the left lateral segmental branches, the right portal vein segments were subcapsularly located. CONCLUSION: Variations of the intrahepatic portal veins can be recognized on CTAP imaging. tomography-Portal vein, computed tomography.     

CT during arterial portography

CT during arterial portography (CTAP) is based on portal enhancement of the liver by infusion of contrast material through the superior mesenteric or splenic artery. This technique provides high degrees of enhancement of the portal vein and intrahepatic vessels, allowing reliable segmental localisation of tumours and accurate assessment of relationships between tumours and intrahepatic vessels. Because of its invasiveness, CTAP must be limited to patients for whom non-invasive preoperative imaging suggests resectable tumour. In the majority of cases, CTAP is performed in patients with hepatic metastases from colorectal cancer, but other types of hepatic tumour (either primary or secondary) and pancreatic tumour may be an indication for CTAP. Visualisation of non-tumorous perfusion defects is a limitation of this technique, but such defects have been well described and have characteristic locations and appearance. In difficult cases, correlation with sonographic, CT and MRI findings helps characterise portal perfusion defects. CTAP is the most sensitive technique for the detection of intrahepatic tumours, and the recent use of spiral technology shows promise in the performance of CTAP. CTAP data can be viewed as multiplanar and three-dimensional reconstructions that allow preoperative planning of the extent of resection and determination of the volume of the remaining liver after resection.     

Pre-operative detection of malignant hepatic tumours: value of combined helical CT during arterial portography and biphasic CT during hepatic arteriography

AIMS: The purpose of our study was to evaluate the observer performance with combined helical CT during arterial portography (CTAP) and biphasic CT hepatic arteriography (CTHA) in the pre-operative detection of malignant hepatic tumours. METHODS: Computed tomography images obtained in 41 patients with suspected hepatic tumours were retrospectively reviewed. In a blind fashion, three off-site, independent radiologists reviewed CTAP and early-phase CTHA combined for the first review, then late-phase CTHA was added for the second review. Statistical analysis was conducted on lesion-by-lesion and segment-by-segment bases; a total of 328 liver segments including 65 segments with 74 malignant hepatic tumours ranging in size from 5 to 100 mm (mean, 21.4 mm) were analysed. RESULTS: Sensitivity for detection of liver segments harbouring tumours of CTAP and biphasic CTHA combined (82%) was identical to that of CTAP and early-phase CTHA combined (82%). Specificity of CTAP and biphasic CTHA combined (93%) was greater than that of CTAP and early-phase CTHA combined (90%, P < 0.005). The mean confidence level for the 74 tumours significantly increased by adding late-phase CTHA (P < 0.0005). The mean confidence level for 100-142 benign perfusion abnormalities detected with CTAP and early-phase CTHA combined significantly decreased by adding late-phase CTHA (P < 0.0005). CONCLUSION: By combining late-phase CTHA with CTAP and early-phase CTHA information, the specificity for the detection of malignant hepatic tumours rises significantly, allowing more accurate preoperative tumour detection.     

Preoperative detection of hepatocellular carcinoma: ferumoxides-enhanced mr imaging versus combined helical CT during arterial portography and CT hepatic arteriography

OBJECTIVE: The purpose of this study was to compare ferumoxides-enhanced MR imaging with combined helical CT during arterial portography and CT hepatic arteriography for preoperative detection of hepatocellular carcinomas. SUBJECTS AND METHODS: Twenty patients with 30 hepatocellular carcinomas underwent ferumoxides-enhanced MR imaging and combined helical CT during arterial portography and CT hepatic arteriography. The diagnosis was established by pathologic examination after surgical resection in 18 patients and by biopsy in two. The MR protocol included fast spin-echo with two echo times, T2(*)-weighted fast multiplanar gradient-recalled acquisition in the steady state, proton density-weighted fast multiplanar spoiled gradient-recalled echo, and T1-weighted fast multiplanar spoiled gradient-recalled echo images. The MR images of all sequences and the paired CT during arterial portography and CT hepatic arteriography images were independently evaluated by three radiologists on a segment-by-segment basis. Diagnostic accuracy was assessed with receiver operating characteristic analysis. RESULTS: The accuracies (A(z) values) of ferumoxides-enhanced MR imaging and combined CT during arterial portography and CT hepatic arteriography for all observers were 0.964 and 0.948, respectively. The mean sensitivities of MR imaging and CT were 93% and 91%, respectively. The differences were not statistically significant. The mean specificity of MR imaging (99%) was significantly higher than that of combined CT during arterial portography and CT hepatic arteriography (94%). CONCLUSION: Ferumoxides-enhanced MR imaging can be used successfully in place of combined CT during arterial portography and CT hepatic arteriography for the preoperative evaluation of patients with hepatocellular carcinomas.     

Intestinal metastases from gastric adenocarcinoma: helical CT findings

PURPOSE: The purpose of this work was to describe the helical CT findings of intestinal metastasis from gastric adenocarcinoma. METHOD: Twenty-three patients with intestinal metastasis from gastric adenocarcinoma found at helical CT were included. CT findings and clinical and pathologic data were reviewed. RESULTS: The most common characteristic finding was target-like concentric bowel wall thickening (thick inner high-outer low, n = 18) involving multiple long segments with progressive thickening of the enhancing inner layer. Fifteen cases (65%) involved multiple sites, and the ascending colon (n = 12) and rectum (n = 11) were the two most common sites. Peritoneal carcinomatosis (n = 15, 65%) and bowel obstruction (n = 14, 61%) were common associated findings. Regarding the primary lesion, the majority was linitis plastica (n = 16) and poorly differentiated adenocarcinoma with or without signet-ring cell differentiation (n = 14). CONCLUSION: Intestinal metastasis from gastric adenocarcinoma, especially of the linitis plastica type, most commonly showed target-like long segmental wall thickening with a characteristically thick inner enhancing layer on helical CT.     

Preoperative segmental localization of hepatic metastases: utility of three-dimensional CT during arterial portography

To evaluate the accuracy of a fast three-dimensional (3D) reconstruction technique in determining the segmental location of hepatic metastases, 14 patients (40 metastases) were prospectively investigated before surgery with dynamic two-dimensional (2D) computed tomography during sequential arterial portography (CTAP). All patients underwent subsequent hepatic tumor resection within 4 days. After computer-generated mapping of hepatic venous structures with high attenuation and metastases with low attenuation, 3D reconstruction was performed. Thirty-six of the 40 lesions (90%) were detected with 2D and 3D CTAP. The accuracy in determining the segmental location of hepatic metastases was 78% (28 of the 36 metastases) for 2D CTAP and 94% (34 of the 36 metastases) for 3D CTAP. The difference in localization rates between 2D CTAP and 3D CTAP was statistically significant. The 3D CTAP technique provides vital data unattainable with other imaging modalities that improve the preoperative assessment of the resectability of hepatic metastases and allows planning a safer surgical approach.     

Hepatic arterioportal shunts not directly related to hepatocellular carcinoma: findings on CT during hepatic arteriography, CT arterial portography and dual phase spiral CT

AIM: To evaluate findings of arterioportal shunts not directly related to hepatocellular carcinoma (HCC) which were seen within third-order portal branches on computed tomography (CT) during hepatic arteriography (CTHA), arterial portography (CTAP), and dual phase spiral CT.MATERIALS AND METHODS: At CTHA in 112 patients, we examined third-order portal vein branches to find arterioportal shunts not directly related to HCC. Six cases were found. We evaluated the findings of these shunts on CTHA and investigated whether CTAP (n = 6) and dual phase spiral CT (n = 5) showed perfusion defects in the corresponding areas on arterioportal shunts. RESULTS: Five of six cases showed abrupt visualization of portal branches without visualization of the proximal portion of CTHA. Five of six cases showed no perfusion defect on CTAP and no hyperattenuating area on CTHA. Four of five cases showed no hyperattenuating area on hepatic arterial phase spiral CT. CONCLUSION: Arterioportal shunts not directly related to HCC and occuring within third-order portal branches mainly showed abrupt visualization of portal branches on CTHA. These occurred frequently without perfusion defects on CTAP and without a hyperattenuating area on CTHA and hepatic arterial phase spiral CT.Park, C. M. (2000). Clinical Radiology55, 465-470.