A genetic test is crucial in diagnosing lung cancer as an increasing number of non-smokers in Hong Kong are being afflicted with the disease.
A leading respiratory diseases researcher at the University of Hong Kong said this yesterday, noting that 60 per cent of sufferers seen by the university's department of medicine did not get the disease from smoking but from a mutated gene.
"We see more patients diagnosed with lung cancer due to genetic factors," Dr James Ho Chung-man said. "The reason behind such a trend is not really clear."
Ho, a clinical associate professor in the department, said treatment with a drug targeting that mutated gene could extend patients' median survival rate from eight months to almost two years.
"I hope the usage of genetic tests can be extended so that more patients can receive personal treatment targeting their conditions," he said.
Ho said patients afflicted with lung cancer often displayed symptoms such as coughing, difficulty in breathing, loss of weight and loss of appetite.
But many felt no symptoms in the early stages and missed the "golden period" for treatment. Non-smokers were more likely to overlook the disease, he said.
Ho's research on 320 lung cancer patients treated at Queen Mary Hospital since 2010 found 60 per cent of cases were linked to the gene problem.
The department has carried out gene tests on patients since 2010, mostly on non-smokers.
"For some patients, lung cancer has turned into a chronic disease that can be controlled by taking pills in the long term," Ho said. "A more extensive use of genetic tests could find more patients who can be better treated."
Ho said gene-analysis technology had been available only for about 10 years and since then, different medicines had been invented to fight different conditions. Before that, all lung cancers were treated by chemotherapy, he said.