Scientists in the United States have developed a test which is able to predict which lung cancer tumours are most likely to recur.
The scientists say that by scanning genes they are able to identify the aggressive cancers which are most likely to return and therefore predict which patients with early-stage lung cancer will benefit from chemotherapy.
This they say means in effect that people at risk could be given the option of chemotherapy as well as surgery, and tailored-made treatment could be offered.
The researchers examined patients with early-stage non-small cell lung cancer (NSCLC), a form of the disease which accounts for about four out of every five lung cancer cases.
Currently people with the earliest stage cancer which is determined by tumour size and whether or not it has not spread beyond the lungs, are offered surgery but not chemotherapy.
However as many as 30% of such patients can expect to suffer a recurrence of the disease.
The research team from the Duke University Medical Center, looked at the genetic profile of NSCLC tumours and found there were significantly different genetic patterns between the tumours that are likely to recur and those that will not.
Dr. Anil Potti, who led the research, says the current staging system for lung cancer is very crude.
It seems that if a patient has a 2.9cm tumour, the tumour is removed, but if a patient has a 3.1cm tumour, the tumour is cut out but they would also receive chemotherapy.
By using the genome test the scientists were able to look at the tumours in 129 patients, whose disease statuses were followed over time.
They discovered the test predicted the risk of recurrence to a high degree of accuracy, about 80 percent.
Dr. Potti says even though everyone knows that 30% of early-stage patients will experience a recurrence, no-one was ever able to say which group would be the most likely to do so.
He says if this test is used with people with very early-stage cancer, those who show a higher likelihood of recurrence could be offered chemotherapy as well as surgery which could potentially save thousands of lives every year.