Doctors at Queen Mary Hospital are using radio frequency waves - similar to those given off by mobile phones - to treat liver tumours, it was announced yesterday. In all, 24 patients suffering from the early stages of liver cancer have undergone the keyhole surgery since the treatment was offered a year ago, said Dr Ronnie Poon Tung-ping, associate professor at the department of surgery at the University of Hong Kong. Radio frequency ablation uses electrical current, passed through a small needle placed directly into the damaged liver, to destroy cancer cells with heat. The new treatment has lower complication rates and leads to better preservation of the liver and better quality of life for patients than the traditional resection surgery, in which patients have part of their organ removed, Dr Poon said. Results from the treatment are being compared to patients who have undergone liver resection. The two-year research will eventually target 160 patients. The comparative study is the first of its type in the world, although the radio frequency ablation treatment was first developed in the West, Dr Poon said, adding that the new treatment, which takes about 12 minutes, has led to 95 per cent of the tumours being destroyed. 'This treatment can be used [on patients] again. This is another advantage. For surgery it is difficult to do repeat operations. Whereas with this one you can theoretically see a new tumour and burn it,' he said. Retiree K. C. Cheung, 62, said he returned to normal within days of the surgery this month. The research is one of several University of Hong Kong medical projects which received a total of $46.1 million from the government-funded Research Grants Council this year. One other project aims to establish the role of an enzyme called PKR in the development of Alzheimer's disease. 'We are trying to prove this pathway using humans and animal models and we are using molecules which can block these enzymes to try to see whether we can stop the evolution of Alzheimer's,' said Professor Jacques Hugon, professor of the department of anatomy. Fifteen patients are involved in the research, which could lead to a new drug being developed. It is estimated there are about 40,000 elderly people in Hong Kong who suffer from Alzheimer's.