A new type of X-ray will be added to regular health examinations in a bid to detect lung cancer at an earlier stage, medical officials said recently.

Lung cancer is the world's biggest cancer killer, and over the past 20 years, the death rate from the disease in China has almost doubled.

Speaking at the third national symposium on chest tumors and endoscopes last month, Dr Bai Chunxue said that because the disease does not show any obvious symptoms in the early stages, it is very hard to detect.

Bai, who is the director of the respiratory diseases department of the Shanghai Medical Association, told the media last Friday that a low-dosage CT scan will now be used to provide a clearer picture of the lungs and help detect tumors in their early stages.

"Traditional X-ray photography can only show a vague picture of the lungs. Also, people are reluctant to be exposed to radiation, which is why I suggest a small-dosage CT scan to minimize the radiation."

Pollution of the environment has resulted in a deterioration of air quality and this has contributed to the numbers of lung cancer victims, Bai said.

"There is the overall environmental problem, and then people have their own personal environments. Such things as smoking, passive smoking, and kitchen smoke can all harm the lungs, and even underground car parks, which are often thick with pollution, can be bad for the health," Bai said.

He said that men aged 40 and above, who have smoked for more than a year, should have their lungs examined annually.

"When symptoms start to show it is usually too late for intervention," Bai explained on the development of the cancer.

"But there is a signal, which should be given special emphasis, and that is a blood trace in the sputum."

About 500,000 new cases of lung cancer are found in China every year.

Two people die of the disease every minute, according to statistics released at the symposium. In Shanghai, 70 out of every 100,000 men, and 40 out of every 100,000 women will contract the disease.

"Only one-third of those detected in the early stages can be operated on," Bai said.

Seventy to 80 percent of them will survive five years or longer after the surgery. But the rest who are diagnosed with lung cancer are not likely to survive more than a year.

Doctors from home and abroad discussed the latest development in the treatment of lung cancer at the symposium. New medicines targeted at controlling and stabilizing tumor cells are showing positive effects in prolonging patients' lives for a year, but the treatment costs 170,000-180,000 yuan per year.

(China Daily May 8, 2007)