New lung cancer testing guideline draws praise from Nova Scotia doctor

A Nova Scotia doctor says a new lung cancer screening guideline has the most promise of any approach to detecting the disease in high-risk adults he has ever seen.

In early March, the Canadian Task Force on Preventive Health Care released a guideline advocating for annual screening — for up to three straight years — of high-risk adults between the ages of 55 and 74 using a low dose CT scan.

A CT scan or computerized tomography is an X-ray procedure that combines many X-ray images taken from different angles. A computer uses those images to create a cross-sectional images of bones and soft tissues.

CT scans produced more detailed images than traditional X-rays, and were formerly known as CAT scans.  

High-risk people are also defined as having been a pack a day smoker for 30 years, or a two pack a day smoker for 15 years.

"It is the most remarkable possibility in reducing mortality from lung cancer that I have seen in my career," said Dr. Drew Bethune, the medical director of Nova Scotia's cancer care program on CBC Radio's Information Morning.

The task force said a recent study found that using low dose CT screening, compared to chest X-rays, resulted in a 15 per cent decrease in lung cancer deaths.

Lung cancer is the most commonly diagnosed cancer in Canada and is the leading cause of death from cancer in both men and women.

Low radiation doses

Bethune said that one of the benefits of the low dose CT scan is the amount of radiation it gives off.

"The new CAT scanners gives a much lower dose of radiation, about the same as six chest X-rays. It makes it feasible to do an annual CAT scan in high-risk patients," he said.

Bethune believes Nova Scotia has the resources to follow this guideline, but said it would generate more tests and more surgeries.

One downside is that the testing can create some psychological concern because of what the scans find.

"We find all sorts of things, but you may not need to do anything about them," said Bethune.

Bethune said the best way to stop lung cancer is to stop smoking.