Comparison of MRI features of pathologically proven hepatocellular carcinoma between patients with hepatitis B and hepatitis C infection

Imaging features of hepatocellular carcinoma in nonalcoholic fatty liver disease and nonalcoholic steatohepatitis: a systematic review and meta-analysis

PURPOSE

To investigate the imaging features of hepatocellular carcinoma (HCC) in patients with non-alcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) through a systematic review and meta-analysis.

METHODS

MEDLINE, EMBASE, and the Cochrane Library database were searched for studies providing data on imaging features of HCC in NAFLD and NASH between January 1, 2011 and July 19, 2021. Random effects models were used to calculate the pooled percentages of the three major features of arterial-phase hyperenhancement (APHE), washout, and enhancing capsule. Sensitivity analysis and subgroup analysis were performed according to underlying liver disease (NASH vs. NAFLD) and imaging modality (CT vs. MRI).

RESULTS

Five studies (170 patients with 193 HCCs) were included in the analysis. The pooled percentages of APHE, washout, and enhancing capsule were 94.0% (95% confidence interval [CI] 89.1-96.7%), 72.7% (95% CI 63.3-80.4%), and 57.5% (95% CI 45.1-69.1%), respectively. The percentages of these three major features did not significantly differ between NAFLD and NASH (p ≥ 0.21). MRI showed similar pooled percentages of APHE (94.3% vs. 93.4%, p = 0.82) and washout (70.4% vs. 77.2%, p = 0.38) to CT, but a higher pooled percentage of enhancing capsule (67.1% vs. 44.7%, p = 0.02).

CONCLUSION

HCC in patients with NAFLD and NASH had a similar frequency of APHE to HCC with other etiology. However, it showed a relatively low frequency of washout and enhancing capsule.

Diagnosis of hepatocellular carcinoma: An update on international guidelines

Imaging is essential for the successful management of patients with or at risk of developing hepatocellular carcinoma (HCC). If ultrasound remains the key screening modality, computed tomography and magnetic resonance imaging (MRI) can play a major role in the characterization and noninvasive diagnosis of nodules in patients at risk of developing HCC. Each technique has succeeded in adapting to the wide histological spectrum of focal liver lesions. In this review, we discuss recent advancements in imaging techniques and evaluation - notably diffusion-weighted imaging, contrast-enhanced ultrasound, and liver-specific MRI contrast agents - as well as their addition to international guidelines and reporting systems such as the Liver imaging reporting and data system (LI-RADS).

Quantitative assessment of washout in hepatocellular carcinoma using MRI

Background

Arterial hyperenhancement and washout on computed tomography and magnetic resonance imaging (MRI) are described by all major guidelines as specific criteria for non-invasive diagnosis of hepatocellular carcinoma (HCC). However, publications on the quantitative assessment of washout in MRI are lacking. Therefore, we evaluated a method for quantitatively measuring and defining washout in MRI in order to determine a cutoff value that allows objective HCC diagnosis.

Methods

We analyzed all patients who underwent liver transplantation for cirrhosis or liver resection for HCC at our institution between 2003 and 2014. Washout was quantitatively investigated by placing a 25-mm² region of interest (ROI) over each nodule and two 25-mm² ROIs over adjacent liver parenchyma. The percentage signal ratio (PSR = 100 × ratio of signal intensity of adjacent liver to that of the lesion) was calculated for each series in both groups. Accordingly, this quantitative measurement was compared to a qualitative approach.

Results

A total of 16 hypervascularized non-HCC nodules and 69 HCC nodules were identified. Interobserver reliability was reasonably good for the measurement of PSRs and readers showed a substantial agreement for the qualitative assessment. In the HCC group, the median PSR was 116.2 at equilibrium and 112.9 in the delayed phase. In the non-HCC group, the median PSR was 93.8 at equilibrium and 96.0 in the delayed phase. Receiver operating characteristic analysis indicated areas under the curve of 0.902 (p < 0.001) and 0.873 (p < 0.001) at equilibrium and in the delayed phase. PSR values of 102 at equilibrium and 101.5 in the delayed phase led to the highest Youden’s index of 0.82 and 0.77, respectively. These PSR cutoffs yielded sensitivities of 82 and 77 %, respectively, with specificities of 100 %. The sensitivity for the qualitative assessment of washout was 88 and 93 % and the specificity was 48 and 56 %. For the classification of HCC, sensitivity yielded 95 and 97 % and specificity was 68 and 56 %, respectively.

Conclusion

Quantitatively measuring HCC washout in MRI is easy and reproducible. It can objectify and support diagnosis of HCC. However, the quantitative measurement of washout can only serve as one of several components of HCC assessment.