Screening heavy smokers annually for lung cancer could save 1500 lives a year in Australia, but it could also lead to scores of false positive results and unnecessary biopsies, doctors say.
Associate Professor Paul Mitchell, a senior oncologist at the Olivia Newton John Cancer and Wellness Centre, said annual low-dose CT scans of long-term smokers aged over 55 would undoubtedly lead to earlier detection of lung cancer, improving treatment options and survival rates.
He said given that a US study of 53,000 current and former heavy smokers aged 55-74 found 20 per cent fewer lung cancer deaths among those screened with low-dose CT, an Australian screening program for people who had smoked a pack a day for 30 years could double the number of patients who live beyond five years with the disease.
''If we applied that same criteria to the Australian population … we might push the current five-year survival rate from 14 per cent to 29 per cent,'' he said. ''It could have a dramatic impact. A lot more women die of lung cancer than from breast cancer. It's the biggest cancer killer in women and men.''
There are no organised lung cancer screening programs in Australia or other countries.
The US Preventive Services Task Force recently issued a draft statement recommending annual low-dose CT screening for healthy people aged 55-79 who have smoked a pack a day for 30-plus years and who have smoked within the past 15 years.
But the US study, which is known as the National Lung Screening Trial, found that while screening saved lives, it also led to many false positive results that caused some patients to have unnecessary invasive biopsies and surgical procedures.
Earlier this year, three Australian doctors said more than 95 per cent of the positive scans in the US study were false positives, meaning no cancer was found. In most cases these false positive results led to more scans, however some patients also had invasive procedures to clear them of cancer.
The doctors estimated that the cost of saving one life through screening would be $530,487 compared with the current $250-$1000 per person spent on smoking cessation interventions which add four years of life to each quitter in their early 60s.
But Associate Professor Mitchell said a recent Victorian study indicated that 62 per cent of smokers presenting with lung cancer had already quit a median of 12 years earlier, meaning smoking cessation programs will not save them.
''Smoking reduction is essential, but it is not an alternative to screening,'' he said. ''I personally think screening is a high priority because it's the one thing we can do now that will make a substantial difference.''