Common Medical Test Predicts Risk of Liver Cancer in General Population
ALT and AST levels predicted 91% of cancer cases (Oct. 16)
A team of scientists in Taiwan and at the University of Texas MD Anderson Cancer Center have reported that enzyme levels in the blood routinely monitored by physicians as liver-function indicators are also the best predictor of the risk for liver cancer in the general population. In a prospective study, two enzymes predicted 91% of liver cancer cases.
The findings were published on October 16 in the Journal of the National Cancer Institute.
The researchers evaluated medical, demographic and lifestyle data from 428,584 people in Taiwan from 1994 to 2008. The average follow-up period was 8.5 years. They found 1,668 cases of liver cancer.
Five risk models were analyzed: 1) health history alone; 2) transaminase enzymes alone; 3) health history plus transaminases; 4) a model that added hepatitis B virus (HBV) status and alpha-fetal protein (AFP) level to the third model; and 5) a model that added hepatitis C virus (HCV) to the other four models. The researchers found:
- The model that relied only on levels of the enzymes alanine transaminase (ALT) and aspartate transaminase (AST) predicted 91% of cancer cases.
- HBV and HCV separately predicted 84% of cases.
- Adding HCV and HBV to the transaminase model increased the predictive power to only 93%.
- All five factors raised the predictive power to 94%.
Elevated levels of ALT and AST, which are involved in producing amino acids, are indicators of liver damage. The scientists found that ALT or AST levels at or above 25 international units per liter of blood were predictive of cancer risk.
Source: MD Anderson Cancer Center, October 16, 2012.