Scientists at Birmingham University are a step closer to devising a blood test which could detect early signs of liver cancer in high-risk patients.

Their study, which was published in the British Journal of Cancer yesterday, revealed how researchers were able to define and detect early signs of liver cancer using sophisticated blood protein spectrum measurements.

People in high-risk groups, such as those with cirrhosis and hepatitis B or C, are currently monitored but existing tests are not sensitive enough to pick up early signs of the disease.

Researchers at the university's Cancer Research UK Institute for Cancer Studies worked with a team of specialists in Paris in devising a test which examines more than 100 blood proteins.

Lead researcher Professor Philip Johnson said: "We've shown that the right combination of technology and computer analysis can 'break the code' of liver cancer and distinguish people with early liver cancer from those without the disease.

"However, this is only the first step on a long road towards a test that can be reliably used for the many people at risk of developing primary liver cancer. We want to improve the technology to make the test even more accurate. The work to date shows that our test has the potential to reveal liver cancer before symptoms show up."

Dr Ashley Martin, a senior research fellow at Birmingham University, added: "By looking at huge numbers of proteins we can detect changes, however subtle they are.

"In layman's terms it's like looking at twins who initially look the same, but the longer you look at them the more differences you can see."

Another team of scientists, also based within the Institute, has been awarded a £500,000 grant to research chronic lymphocytic leukaemia. More than 2,700 people a year in Britain are diagnosed with the disease.