2022 Korean Liver Cancer Association-National Cancer Center Korea Practice Guidelines for Imaging Diagnosis of Hepatocellular Carcinoma: What’s New?

Diagnosing Hepatocellular Carcinoma Using Sonazoid Contrast-Enhanced Ultrasonography: 2023 Guidelines From the Korean Society of Radiology and the Korean Society of Abdominal Radiology

“…During hepatocarcinogenesis, the density of the unpaired arteries progressively increases [ 8 ]. Therefore, more enhancement in the arterial phase than in the liver without peripheral rim enhancement on computed tomography (CT)/magnetic resonance imaging (MRI) (nonrim APHE) is a major imaging feature for diagnosing HCC in at-risk patients [ 9 10 11 12 ]. Similarly, APHE on Sonazoid CEUS is an important imaging feature for diagnosing HCC in at-risk patients.…”

“…This results in a washout appearance, defined as a temporal reduction in enhancement relative to the composite liver tissue from earlier to later phases [ 10 ]. Thus, washout on CT/MRI is a major imaging feature for the diagnosis of HCC in at-risk patients [ 9 10 11 12 ]. Unlike CT/MRI, early CEUS studies reported that washout appearance was insufficient to differentiate HCC from ICC [ 15 ].…”

Impact of the updated KLCA-NCC criteria for diagnosis of “probable HCC” in liver MRI: comparisons between KLCA v2022 and v2018

“…This change was made based on studies reporting a high probability of HCC or HCC progression in LR-3 or LR-4 observations with APHE compared to those without APHE. [3][4][5] In this issue of Journal of Liver Cancer , Yoon et al 6 specificity between KLCA-NCC v2018 and v2022 because the criteria for "definite HCC" remained the same in each modality. However, when the authors expanded the criteria of test positive as both "definite HCC" and "probable HCC", the sensitivity of KLCA-NCC v2022 significantly increased on ECA-MRI compared with that of KLCA-NCC v2018 (85.3% vs. 78.3%, P=0.002) without significant difference of specificity (93.6% for each).…”

“…The latest KLCA-NCC v2022 includes several changes to the non-invasive diagnostic flow and HCC criteria on computed tomography and MRI, in addition to the inclusion of a new first-line imaging modality (Kupffer cellspecific contrast-enhanced ultrasound). 3 Regarding the diagnostic flow, probable HCC can be diagnosed based on the first line examination, instead of mandating a second line examination. This is because additional examination may be difficult to perform for clinical reasons, or the benefit of the second screening is unclear.…”

“…This change was made based on studies reporting a high probability of HCC or HCC progression in LR-3 or LR-4 observations with APHE compared to those without APHE. 3 - 5 …”