Korean J Radiol.  2016 Feb;17(1):7-24. 10.3348/kjr.2016.17.1.7.

Noninvasive Diagnosis of Hepatocellular Carcinoma: Elaboration on Korean Liver Cancer Study Group-National Cancer Center Korea Practice Guidelines Compared with Other Guidelines and Remaining Issues

• Yoon JH
• Park JW
• Lee JM

• KMID: 2351159
• DOI: http://doi.org/10.3348/kjr.2016.17.1.7

Abstract

Hepatocellular carcinoma (HCC) can be diagnosed based on characteristic findings of arterial-phase enhancement and portal/delayed "washout" in cirrhotic patients. Several countries and major academic societies have proposed varying specific diagnostic criteria for HCC, largely reflecting the variable HCC prevalence in different regions and ethnic groups, as well as different practice patterns. In 2014, a new version of Korean practice guidelines for management of HCC was released by the Korean Liver Cancer Study Group (KLCSG) and the National Cancer Center (NCC). According to the KLCSG-NCC Korea practice guidelines, if the typical hallmark of HCC (i.e., hypervascularity in the arterial phase with washout in the portal or 3 min-delayed phases) is identified in a nodule > or = 1 cm in diameter on either dynamic CT, dynamic MRI, or MRI using hepatocyte-specific contrast agent in high-risk groups, a diagnosis of HCC is established. In addition, the KLCSG-NCC Korea practice guidelines provide criteria to diagnose HCC for subcentimeter hepatic nodules according to imaging findings and tumor marker, which has not been addressed in other guidelines such as Association for the Study of Liver Diseases and European Association for the Study of the Liver. In this review, we briefly review the new HCC diagnostic criteria endorsed by the 2014 KLCSG-NCC Korea practice guidelines, in comparison with other recent guidelines; we furthermore address several remaining issues in noninvasive diagnosis of HCC, including prerequisite of sonographic demonstration of nodules, discrepancy between transitional phase and delayed phase, and implementation of ancillary features for HCC diagnosis.

Keyword

Hepatocellular carcinoma; Diagnosis; Criteria; Practice guideline

MeSH Terms

Aged
Aged, 80 and over
Carcinoma, Hepatocellular/*diagnosis/pathology
Contrast Media
Female
Hepatitis B, Chronic/complications
Hepatitis C, Chronic/complications
Humans
Liver/*pathology
Liver Neoplasms/*diagnosis/pathology
Magnetic Resonance Imaging/*methods
Male
Middle Aged
Practice Guidelines as Topic
Republic of Korea
Young Adult
Contrast Media

Figure

• 

  Fig. 1 Diagnostic algorithm for suspected hepatocellular carcinoma (HCC) with new Korean Liver Cancer Study Group-National Cancer Center Korea practice guideline. Typical imaging features of HCC include following: 1) arterial enhancement and 2) portal venous or delayed phase washout. AFP = alpha-fetoprotein, CHB = chronic hepatitis B, CHC = chronic hepatitis C, LC = liver cirrhosis, US = ultrasonography

• 

  Fig. 2 CT and MR images in 24-year-old male patient without viral hepatitis but portal hypertension. A, B. 2.2 cm mass is seen in S3 showing arterial "wash in" and portal "washout". C. Mass shows hyperintensity on hepatobiliary phase on gadoxetic acid-enhanced MRI. D. On repeated biopsy, nodule was diagnosed as focal nodular hyperplasia like nodule in background liver with periportal fibrosis.

• 

  Fig. 3 Gadoxetic acid-enhanced MRI in 69-year-old man with chronic hepatitis C. On arterial phase (A), 1.2 cm enhancing nodule is seen in S8 (arrows), which is hyper-, hypo-, and hypointense on portal venous (B), transitional (C), and hepatobiliary (D) phases. Western guidelines are not applicable and it does not meet criteria of LR-5, but nodule is diagnosed with hepatocellular carcinoma according to Korean Liver Cancer Study Group-National Cancer Center and Japan Society of Hepatology guidelines.

• 

  Fig. 4 Surgically confirmed cholangiocarcinoma in 49-year-old man. On gadoxetic acid-enhanced MRI, there is approximately 7 cm arterially enhancing mass in S8 (A, arrowheads). Mass (arrowheads) shows isointensity on portal venous phase (B) and hypointensity on transitional (C) and hepatobiliary (D) phases, as compared with surrounding liver parenchyma. Mass can be diagnosed with hepatocellular carcinoma on basis of Korean Liver Cancer Study Group-National Cancer Center guideline, whereas it does not meet Liver Imaging Reporting and Data System recommendation that only accepts "portal washout".

• 

  Fig. 5 Gadoxetic acid-enhanced MRI in 66-year-old man with chronic hepatitis B. On precontrast T1-weighted (A), arterial (B), and portal venous phase (C) images, no focal lesion is shown in liver. On the hepatobiliary phase (D), 1.2 cm defect is revealed in S7/8 (arrows). Nodule was not delineable on T2- or diffusion weighted images. After fusion biopsy, nodule was diagnosed as well-differentiated hepatocellular carcinoma.

• 

  Fig. 6 Gadoxetic acid-enhanced MRI in 60-year-old man with chronic hepatitis B. A, B. On initial MRI, 1.3 cm nonhypervascular hypointense nodule (arrows) is observed in S8. C, D. Nine months later, nodule showed interval development of arterial enhancement in nodule (arrowhead) with interval growth (2.2 cm, arrows) on follow-up MRI.

• 

  Fig. 7 Histologically confirmed hepatocellular carcinoma in 81-year-old man with chronic hepatitis B. 3.3 cm mass (arrows) is incidentally found in S7 showing "wash in" on arterial phase (A) without "washout" on portal venous phase (B). On transitional (C) and hepatobiliary (D) phases of gadoxetic acid-enhanced MRI, mass remains as hyperintense. Although it shows discrete rim (B-D), mild T2 high signal intensity (E), diffusion restriction (F), which is suggestive of malignancy, mass does not meet Association for Study of Liver Diseases, European Organization for Research and Treatment of Cancer, Korean Liver Cancer Study Group-National Cancer Center diagnostic criteria, and LR-5. On delayed phase CT scan (G), tumor shows enhanced rim, which meets definition of "capsule" according to Liver Imaging Reporting and Data System and Organ Procurement and Transplantation Network, and hypointense rim on transitional phase of MR might be result of "pseudo-washout".

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