LOS ANGELES, April 15 (Xinhua) -- Blood DNA can be an early predictor for liver cancer, according to a study published in the April 15 issue of Clinical Cancer Research.

    Using DNA isolated from serum samples as a baseline biomarker, researchers at Columbia University's Mailman School of Public Health have discovered a means for early detection of liver cancer, according to the study.

    The scientists examined changes in certain tumor suppressor genes that have been associated with the development of liver carcinomas.

    The researchers studied the blood of patients enrolled in a cancer screening program in Taiwan, who provided repeated blood samples prior to diagnosis. A total of 12,000 males and over 11,900 females recruited during 1991-1992 are being followed.

    With screenings of these patients, scientists found changes associated with cancer in serum DNA, presumably released from the tumor, one to nine years before actual clinical diagnosis.

    Since most hepatocellular or liver carcinomas (HCC) are diagnosed at an advanced and usually fatal stage, the development of screening methods for early detection is critical.

    Certain clinical risk factors such as age and hepatitis B and Cvirus infections, are well-documented risk factors for the development of HCC in the study.

    According to the findings, these factors coupled with smoking and alcohol status, and alterations found in this study in serum DNA, resulted in an overall predictive accuracy of 89 percent for detection of HCC.

    This is the first study to prospectively examine potential biomarkers for early detection of liver cancer in high-risk populations, including those with chronic hepatitis B and C virus infections.

    HCC is one of the most common deadly diseases worldwide, which claims the lives of almost 500,000 people annually.

    The findings are extremely encouraging, said Regina Santella, professor of Environmental Health Sciences at the Mailman School of Public Health.

    Having the tools to identify liver cancer at earlier stages is truly a breakthrough for addressing the challenges of this highly lethal form of cancer, she said.