Maybe it is time to reconsider screening for lung cancer

I never thought it would be worthwhile. I had a neighbor once who had a small lung cancer found on a routine chest x-ray It was removed and he never had a problem with the disease again. Maybe his life was saved. But, many year ago, the Mayo Clinic did a study where they performed chest x-rays on a large number of smokers and found a lot of small cancers that were removed. But when they compared the number of deaths from lung cancer in this group with a similar group of smokers who didn’t get chest x-rays, there was no difference. They hadn’t saved any lives with their chest x-rays.

The explanation for this is that many lung cancers probably start and then stop and go away; the bad ones that don’t go away are killers and catching them early, I thought, might not do much good. And lung cancer is indeed a killer. Around 150,000 people die of the disease in the U.S. each year. This number is going down slowly as fewer people smoke, but there are still over ninety million smokers in the U.S. so this killer isn’t going away soon.

When CT scans were developed, we learned that they were a lot better at finding small early lung cancers than plain chest x-rays. The question became not whether they would find cancers early. Rather it became whether finding the cancer early with CT scans would save lives. Now the answer is in. They do save lives.

In 2002, a group of doctors from around the country, supported by the National Cancer Institute, enrolled over 50, 000 current or former heavy smokers older than 55 in a study to determine the life-saving benefits of chest CT scans. The quitters must have quit less than 15 years before the study began. Half the participants received chest CT scans every year for three years and the other half only got chest x-rays. At the study’s end, 443 people in the chest x-ray group died of lung cancer while there were only 356 deaths in the CT group – 87 fewer.

So it appears that 87 lives were saved by this study at the time it was written up. This is about one out of every 300 persons screened with the CT scans. This is very good. Depending on the cost of the scan, which is around $500, screening 300 people and saving one life would cost $150,000. As a form of cancer treatment this is cheap. Some of the newer drugs for treating lung cancer could come close to that – for one person – and they don’t save lives – just prolong them for a few months.

There is one problem with CT scans. Because the CT scans are so sensitive, they often find small abnormalities that aren’t cancer. Sometimes these need to be biopsied. But the savvy doctors in the study were able to keep these to a minimum.

More analysis needs to be done and more of the ongoing European studies completed before a final word is in. But, this may be a real breakthrough in screening.

Still – not smoking is the best treatment of all – remember 356 people in the CT-screened group couldn’t be saved and wouldn’t have died if they hadn’t smoked.