Chances of survival for lung cancer patients may go up with the findings of a joint team of Australian and American researchers who just found the secret of why the ailment regenerates despite chemotherapy.

The researchers from Monash University helped scientists from Stanford and John Hopkins Universities discover a drug to block a type of protein called hedgehog which is responsible for growth in cells.

Although lung cancer patients usually respond well to chemotherapy and go into remission, in many cases the cancer returns and causes the patient to eventually die. The fast spread of the lung cancer cells results in only 5 per cent survival rate for patients that last up to five years.

For years scientists have been puzzled by failure to detect through scans traces of lung cancer cells after chemotherapy.

"What we found was that... the hedgehog is very important when the cells are depleted down to a tiny population and are asked to regenerate the tumour," Professor Neil Watkins of the Monash Institute of Medical Research told the Australian.

"If you use drug that blocks the hedgehog signaling (for the cancer cells to regenerate) you can prevent small cell lung cancer cells from regenerating after chemotherapy," he added.

Their approach differs from standard cancer studies which focus on shrinking existing tumors.

Lung cancer is the most common cause of cancer deaths in Australia. About 15 to 20 per cent of lung cancers in the country are the small cell lung cancer type which usually responds well to treatment with chemotherapy but relapses with lesser response to treatment.

RELATED STORIES