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Hepatocellular carcinoma (HCC) secondary to chronic viral hepatitis is a major health problem in Asian-Pacific regions due to the endemics of chronic hepatitis B and C virus infection. HCC surveillance has been recommended to patients who are at risk to develop HCC. Unfortunately, a significant proportion of patients still died in long run due to tumor recurrence. The key components of an optimal surveillance program include an accurate tumor biomarker and optimal surveillance interval. Serum alpha-fetoprotein (AFP), despite of being the most widely used biomarker for HCC surveillance, it was criticized as neither sensitive nor specific. Other HCC biomarkers, including lectin-reactive AFP (AFP-L3), des-gamma carboxyprothrombin, are still under investigations. Recent study showed cancer-associated genome-wide hypomethylation and copy number aberrations by plasma DNA bisulfite sequencing to be accurate with both sensitivity and specificity close to 90% in detecting HCC in a case-control study. Concerning the optimal surveillance interval, we believe one size does not fit all patients. Accurate risk prediction to assist prognostication with well-validated HCC risk scores would be useful to decide the need for HCC surveillance. These key components of an optimal HCC surveillance program should be further validated at a surveillance setting.

Chronic hepatitis B (CHB)-related hepatocellular carcinoma (HCC) is a major health problem in Asian-Pacific regions. Antiviral therapy reduces, but does not eliminate the risk of HCC. It would be a heavy financial burden in most low and middle economic countries if all CHB patients received antiviral therapy and HCC surveillance. Thus, there is a need for accurate risk prediction to assist prognostication, decisions on the need for antiviral therapy and HCC surveillance. A few well-established risk factors for HCC, namely advanced age, male gender, high viral load, cirrhosis etc., are the core components of three HCC risk scores: CU-HCC, GAG-HCC and REACH-B scores. These 3 scores were confirmed to be accurate in predicting HCC up to 10 years in treatment-naïve patients. Their validity and applicability have recently been demonstrated in a large cohort of entecavir treatment patients. A decrease in risk scores after antiviral therapy translates to a lower risk of HCC. These findings support the application of HCC risk scores in all CHB patients. Different levels of care and different intensities of HCC surveillance should be offered according to the risk profile of patients. Patients at risk of HCC should undergo regular HCC surveillance, even when they are receiving antiviral treatment.

Assessment of liver fibrosis and steatosis is crucial in chronic liver diseases in order to determine the prognosis, the need of treatment, as well as monitor disease progression and response to treatment. Liver biopsy is limited by its invasiveness and patient acceptability. Transient elastography (TE, Fibroscan(®)) is a non-invasive tool with satisfactory accuracy and reproducibility to estimate liver fibrosis and steatosis. TE has been well validated in major liver diseases including chronic hepatitis B and C, non-alcoholic fatty liver disease, alcoholic liver disease, primary biliary cirrhosis, and primary sclerosing cholangitis. As alanine aminotransferase (ALT) is one of the major confounding factors of liver stiffness in chronic hepatitis B, an ALT-based algorithm has been developed and higher liver stiffness measurements (LSM) cutoff values for different stages of liver fibrosis should be used in patients with elevated ALT levels up to 5 times of the upper limit of normal. Otherwise falsely-high LSM results up to cirrhotic range may occur during ALT flare. TE is also useful in predicting patient prognosis such as development of hepatocellular carcinoma (HCC), portal hypertension, post-operative complications in HCC patients, and also survival. Unfortunately, failed acquisition of TE is common in obese patients. Furthermore, obese patients may have higher LSM results even in the same stage of liver fibrosis. The new XL probe, a larger probe with lower ultrasound frequency and deeper penetration, increases the success rate of TE in obese patients. The median LSM value with XL probe was found to be lower than that by the conventional M probe, hence cutoff values approximately 1.2 to 1.3 kPa lower than those of M probe should be adopted. Recent studies revealed a novel ultrasonic controlled attenuation parameter (CAP) of the machine is a useful parameter to detect even low-grade steatosis noninvasively. CAP may also be used to quantify liver steatosis by applying different cutoff values. As both LSM and CAP results are instantly available at same measurement, this makes TE a very convenient tool to assess any patients who are suspected or confirmed to suffer from chronic liver diseases.

Patients with liver cirrhosis are at increased risk of hepatocellular carcinoma (HCC). Conventional or baseline ultrasound (BUS) is often used as the first-line tool for HCC surveillance or detection, but the accuracy of BUS in HCC detection or differentiation from other focal liver lesions (FLLs) is limited. Contrast-enhanced ultrasound (CEUS) represents a recent revolution in the field of ultrasonography and it has become increasingly important in the detection and evaluation of FLLs. In CEUS, HCC typically exhibits arterial hyper-enhancement and portal-venous washout represented by hypo-enhanced lesions in the portal venous and late phases. The detection rate of HCC was significantly higher with CEUS compared with BUS. Even regenerative or some dysplastic nodules may exhibit arterial hyper-enhancement as they are differentiated from HCC by its iso-enhancing pattern in portal and late phases. The contrast-enhancement patterns of other different types of benign and malignant FLLs, as well as their detection rates with CEUS, were also discussed.