Hepatocellular Carcinoma Screening With Computed Tomography Using the Arterial Enhancement Fraction With Radiologic-Pathologic Correlation

Abstract

Objective: The aim of this study was to investigate the performance of the arterial enhancement fraction (AEF) in multiphasic computed tomography (CT) acquisitions to detect hepatocellular carcinoma (HCC) in liver transplant recipients in correlation with the pathologic analysis of the corresponding liver explants. Materials and Methods: Fifty-five transplant recipients were analyzed: 35 patients with 108 histologically proven HCC lesions and 20 patients with end-stage liver disease without HCC. Six radiologists looked at the triphasic CT acquisitions with the AEF maps in a first readout. For the second readout without the AEF maps, 3 radiologists analyzed triphasic CT acquisitions (group 1), whereas the other 3 readers had 4 contrast acquisitions available (group 2). A jackknife free-response reader receiver operating characteristic analysis was used to compare the readout performance of the readers. Receiver operating characteristic analysis was used to determine the optimal cutoff value of the AEF. Results: The figure of merit (θ = 0.6935) for the conventional triphasic readout was significantly inferior compared with the triphasic readout with additional use of the AEF (θ = 0.7478, P < 0.0001) in group 1. There was no significant difference between the fourphasic conventional readout (θ = 0.7569) and the triphasic readout (θ = 0.7615, P = 0.7541) with the AEF in group 2. Without the AEF, HCC lesions were detected with a sensitivity of 30.7% (95% confidence interval [CI], 25.5%-36.4%) and a specificity of 97.1% (96.0%-98.0%) by group 1 looking at 3 CT acquisition phases and with a sensitivity of 42.1% (36.2%-48.1%) and a specificity of 97.5% (96.4%-98.3%) in group 2 looking at 4 CT acquisition phases. Using the AEF maps, both groups looking at the same 3 acquisition phases, the sensitivity was 47.7% (95% CI, 41.9%-53.5%) with a specificity of 97.4% (96.4%-98.3%) in group 1 and 49.8% (95% CI, 43.9%-55.8%)/97.6% (96.6%-98.4%) in group 2. The optimal cutoff for the AEF was 50%. Conclusion: The AEF is a helpful tool to screen for HCC with CT. The use of the AEF maps may significantly improve HCC detection, which allows omitting the fourth CT acquisition phase and thus making a 25% reduction of radiation dose possible. 3 The most cost-effective strategy to screen patients with chronic liver disease for HCC is sonography with testing of the serum alpha-fetoprotein level every 6 months.4 But a low sensitivity of ultrasound for HCC detection favors screening with computed tomography (CT), especially for patients on the orthotopic liver transplantation (OLT) list. 5,6 During the last few years, there were several published papers showing an increased detectability of HCC lesions with CT perfusion. 7-10Beneath the motion artefacts, 1 major limitation for CT perfusion is the high radiation dose, especially in a setting of long-duration HCC surveillance in patients on the OLT list.11 The calculation of the arterial enhancement fraction (AEF), as introduced by Kim et al,12 allows the calculation of a quantitative colored ...

Added value of spectral parameters for the assessment of lymph node metastasis of lung cancer with dual-layer spectral detector computed tomography

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Predicting epidermal growth factor receptor mutations in non-small cell lung cancer through dual-layer spectral CT: a prospective study

“…Studies have shown quantitative color mapping of the AEF, the ratio of CT value between the AP and the portal venous phase, could increase the diagnostic performance of hepatocellular carcinoma [ 34 ]. However, few studies have investigated the clinical value of AEF or NAEF, defined as the ratio of IC or NIC in the arteriovenous phase.…”

Clinical value of AEF in the post-processing technique of liver perfusion-like phase III enhanced CT scan in evaluating the degree of liver function impairment in patients with Hepatitis-B cirrhosis

“…In this way, abnormal blood perfusion of portal vein and portal artery occurs. [19][20][21] It has been pointed out by some studies that significant differences were observed between hAEF of cirrhosis of different severity and that of normal control group 22,23 , suggesting that the severity of patients' condition may be determined by testing hAEF. In this study, hAEF and H/S values of patients with different Child-Pugh grades were analyzed, and the results showed that the AUC of hAEF and H/S values in evaluating the degree of liver function impairment of patients were 0.716 and 0.770, respectively, indicating that hAEF and H/S values are valuable in evaluating the degree of liver function impairment of patients with hepatitis B cirrhosis.…”