RPS 1401 - Dos and don'ts for liver imaging reporting and data system (LI-RADS)

Purpose:

Liver imaging reporting and data system (LI-RADS) category 5 (LR-5) denotes 100% certainty of hepatocellular carcinoma. The assignment of LR-5 is based on combinations of major features (size, arterial phase hyperenhancement [APHE], “washout” [WO], enhancing “capsule”, threshold growth). The goal of this study is to assess the proportion of LR-5 observations reported clinically that did not meet LR-5 criteria based on reported major features using LI-RADS v2017 and v2018.

Methods and materials:

All MR and CT reports using a standardised LI-RADS macro between 4/17–8/19 were reviewed. For each reported LR-5 observation, all major features and LI-RADS version (v2017 or v2018) were extracted from the clinical report. Based on the reported major features, we determined whether LR-5 criteria were met for each observation.

Results:

237 observations in 181 patients (68% male, mean age 65.6 years) were reported as LR-5, including 137 (58%) reported with v2017 (median size 23 mm) and 100 (42%) with v2018 (median size 18 mm). 9/137 (7%) v2017 LR-5 observations and 4/100 (4%) v2018 LR-5 observations did not meet LR-5 criteria based on reported major features. Of the 9 incorrectly categorised v2017 observations, 3 (33%) lacked APHE, 1 (11%) was < 10 mm, 1 (11%) was 16 mm new observation with APHE only, and 4 (44%) were 10-19 mm with APHE and WO as the only other major feature. Of the 4 incorrectly categorised v2018 observations, 3 (75%) lacked APHE and 1 (25%) was < 10 mm.

Conclusion:

Based on reported major features, 4-7% of clinically reported LR-5 observations do not meet LR-5 criteria. Methods such as education and decision support tools may help to reduce the frequency of these reporting errors.

Limitations:

Retrospective single institution study.

Ethics committee approval

IRB-approved. Informed consent was waived.

Funding:

No funding was received for this work.

Purpose:

To identify preoperative gadoxetic acid enhanced-magnetic resonance (MR) imaging biomarkers for prediction of early recurrence (2 years) after curative resection for liver imaging reporting and data system category 5 (LR-5) hepatocellular carcinoma (HCC).

Methods and materials:

Between July 2015 and July 2018, this retrospective study evaluated consecutive treatment-naïve, high-risk patients who underwent gadoxetic acid–enhanced MR examination within 1 month before surgical resection for HCC. All MR images were reviewed by two independent radiologists. Predictive clinical and imaging features for early recurrence were identified by univariate and multivariate analysis.

Results:

A total of 126 patients with 167 LR-5 HCCs were included; 62 (49.2%) patients had postoperative tumour recurrence within 2 years. Four MR imaging features and serum AFP were independently associated with early recurrence: peritumoural hypointensity on hepatobiliary phase (HBP) (odds ratio [OR] = 6.68; 95% CI: 1.437, 31.081), corona enhancement (OR = 3.997; 95% CI: 1.238, 12.905), tumour size >5 cm (OR = 3.629; 95% CI: 1.137, 11.586), multifocality (OR = 3.141; 95% CI: 1.011, 9.763), and AFP level > 400 ng/mL (OR = 3.262; 95% CI: 1.242, 8.569). The AUCs of the combined models comprising only predictive MR imaging features and MR features along with serum AFP were 0.783 (95% CI: 0.704, 0.862) and 0.797 (95% CI: 0.719, 0.875), respectively.

Conclusion:

In high-risk patients with LR-5 HCC, preoperative HBP peritumoral hypointensity, corona enhancement, tumour size, multifocality, and serum AFP can be used to predict early recurrence after curative hepatectomy.

Limitations:

The retrospective design may cause a selection bias.

Ethics committee approval

n/a

Funding:

This work was supported by the National Natural Science Foundation of China (No. 81771797).

Purpose:

To retrospectively evaluate LI-RADS ancillary imaging features and outcomes of indeterminate lesions lacking APHE in cirrhotic patients.

Methods and materials:

In this retrospective study, we included indeterminate lesions (LR-3 and LR-4) up to 3 cm lacking APHE in consecutive cirrhotic patients imaged with CT or MRI. All MRI exams were performed with Gd-EOB-DTPA. All lesions were individually evaluated to determine LI-RADS major and ancillary imaging features at diagnosis and outcome. Reference standard was based on pathology and imaging follow-up.

Results:

27 lesions lacking APHE, 20 LR-3 and 7 LR-4, in 12 cirrhotic patients (10M, 2F) were included. HCC was proved for 4 [15%] of 27 lesions, including 1 of 10 (10%) lesions imaged with CT, and 3 of (17%) 17 lesions imaged with MRI. Not-HCC malignancy was diagnosed in 1 lesion imaged with MR. Imaging analysis of these 5 malignant lesions showed none of the ancillary features suggesting malignancy on the lesion imaged with CT. Conversely, at least one ancillary feature suggesting malignancy was detected in the remaining 4 lesions imaged with MR (i.e., hepatobiliary phase hypointensity in 4, restricted diffusion in 3, fat in the mass in 3, and T2-hyperintensity in 2).

Conclusion:

HCC is identified in 10% and 17% of indeterminate LR-3 or LR-4 lesions lacking APHE imaged with CT or Gd-EOB-DTPA MRI, respectively. MRI may allow the detection of LI-RADS ancillary features suggesting malignancy and therefore those lesions requiring more aggressive management.

Limitations:

Small sample size, retrospective design, no inter-reader assessment.

Ethics committee approval

IRB approved, waiver of informed consent obtained.

Funding:

No funding was received for this work.

Purpose:

To assess the long-term evolution of observations with low (LR-2), intermediate (LR-3), and high (LR-4) probability for hepatocellular carcinoma (HCC) in cirrhotic patients with hepatitis C treated with direct-acting antivirals (DAA).

Methods and materials:

This retrospective study assessed 2017 consecutive HCV patients treated with DAA between 2015 and 2019. Inclusion criteria were: i) cirrhosis or prior history of HCC, ii) available contrast-enhanced liver imaging studies (CT or MRI), iii) multiple follow-ups before and after DAA, and iv) at least one indeterminate lesion before DAA. Two radiologists reviewed imaging studies, recorded major imaging features, and categorised each lesion according to the LI-RADSv2018. Differences in evolution before and after DAA were evaluated using the Pearson χ2 or Fisher exact test. The cumulative risk of LR-5 was calculated by using the Kaplan-Meier method.

Results:

Final population included 67 patients (mean age 69.5±10.8 years) with 109 observations (mean size 11.8±6.7 mm), including 31 (28.4%) LR-2, 67 (61.5%) LR-3, and 11 (10.1%) LR-4, with a mean follow-up of 44±23 months. Evolution of indeterminate observations to LR-5 was more common before DAA than after DAA (before DAA: 0 (0%) LR-2, 11 (16.4%) LR-3, and 8 (72.7%) LR-4 evolved to LR-5 vs. after DAA: 1 (3.2%) LR-2, 10 (14.9%) LR-3, and 1 (9.1%) LR-4 evolved to LR-5; p<0.001). Cumulative risk for LR-5 evolution was 15.5% at 6 months, 23.8% at one year, and 37.6% at two years. LI-RADS category was significantly associated with risk of progression into LR-5 (p<0.001).

Conclusion:

The use of DAA therapy does not increase progression of indeterminate lesions into definitively HCC.

Limitations:

Retrospective, small sample, lack of cohort of HCV cirrhotic patients not treated with DAA.

Ethics committee approval

IRB-approved study, informed consent was waived.

Funding:

No funding was received for this work.