A new risk score for selecting individuals at risk for hepatocellular carcinoma (HCC) for ultrasound-based cancer screening performs with good predictive accuracy across diverse cohorts and subgroups, providing significant improvement in benefit when compared with the American Association of the Study of the Liver Diseases (AASLD) guidelines. These are the findings of a population-based cohort study of adults in Taiwan led by Dr. Ming-Whei Yu of the National Taiwan University, with her doctoral student Ms. Yi-Chun Hung as first author. This study has been published online in Hepatology since November 21, 2014.
HCC is a leading cause of cancer-related deaths worldwide, and most of the cancer burden is born in Asian countries, where hepatitis B is endemic. Liver ultrasound can identify HCCs while they are still treatable. There is evidence showing that ultrasonography-based mass screening for HCC reduces mortality. The AASLD guidelines recommend routine screening based on hard cutoffs for age and hepatitis virus status, but substantial numbers of persons who do not meet the recommended criteria still develop HCC.
“The best way to identify those at high risk for HCC remains an important question. A scoring system could help for stratifying average-risk population for mass HCC screening” said Dr. Yu.
For this study, Ms. Hung assembled a pooled cohort database of 12377 adults from three large cohorts, in which 75 percent of the participants were between the ages of 20-49 years at enrollment and have been followed over 10-20 years across the predominant age period of HCC onset. By study’s end, 387 HCCs occurred.
In their development of risk scoring system, researchers looked at a number of common risk factors underlying most HCCs in the world — including age, sex, serum alanine aminotransferase levels, prior chronic liver disease, family history of HCC, and cumulative smoking — and assigned them scores based on their contribution to HCC.
The authors noted that the use of the score in selecting persons for screening improved benefit at threshold probabilities of >2 percent 10-year risk, compared with AASLD guidelines and a strategy of screening all hepatitis B carriers. Using the 10-year risk 2 percent for initiating screening, the screening age ranged from 20 to ≥60 years depending on the tertile of risk scores and status of hepatitis B/C virus infection. Combining risk-score tertile levels and hepatitis virus status to enroll individuals into screening program resulted in higher sensitivity than AASLD guidelines for HCC detection within 10 years (89.4 percent vs. 76.8 percent), especially for young-onset HCCs <50 years (79.4 percent vs. 40.6 percent), under slightly lower specificity (67.8 percent vs. 71.8 percent).
“Applying the scoring system can more efficiently identify asymptomatic individuals for ultrasound screening for HCC.” said Ms. Hung. In addition, concluded by Dr. Yu, “this risk score using accessible information can be applied as an interactive risk assessment tool to communicate knowledge about risk to individuals or subgroups, as well as to motivate adherence to the intensity of HCC screening or other preventive programs.”