Who should be screened?
Without further ado, if you are between the ages of 55-80 and you have smoked 30 pack years (Packs per day x years smoked), you should be screened for lung cancer. Screening involves a CT of your lungs. There is no evidence to support screening by chest X-rays. If you have quit smoking more than 15 years ago then you do not have to be screened for lung cancer.
What are the upsides of screening for lung cancer?
There are a number of studies on the matter, not surprisingly with conflicting evidence. However looking a little bit deeper we can develop a clearer picture. The largest of the studies in the US contained more than 50,000 participants, and checked the differences in mortality rates among other factors in smokers, part of which were screened with a chest CT, others with an X-ray and the third group was not screened. The group that was screened with a CT showed a 16% reduction in mortality from lung cancer, as well as a 6.7% reduction in mortality from any cause.
Alternatively there were a few European studies that failed to show a statistically significant benefit of screening individuals who smoked but were asymptomatic. These trials were notably smaller than the one mentioned above, and contained less younger and healthy individuals. The combined data of all of these studies has yet to be accumulated and reported.
What are the downsides of screening for lung cancer?
There are risks to screening for lung cancer, as opposed to many other screening tests that I’ve written about such as blood tests, family history taking or urine samples. Incidental findings in lung cancer can lead to invasive procedures which are potentially dangerous, like biopsies, bronchoscopy, more imaging, and sometimes surgery.
Here’s an interesting number from the larger study mentioned above: Out of all of the asymptomatic people that had a positive finding on the screening exam, 96.4% of those findings turned out to be negative. Out of those positive tests, 2.5% required invasive procedures afterwards. Those invasive procedures have a small rate of complications, including death.
The bottom line
At the end of the day, the various medical organizations that release recommendations need a yes or no answer if it is beneficial or not. However this answer comes with a degree of certainty of the benefit in contrast to the risks. In this situation, there is a clear cut recommendation with what they define as ‘moderate certainty’. It’s important to fully understand the risk and benefits leading to those recommendations, and really digest the fact that this is not a binary subject.
*Please comment to us if you found this information useful, or if you have any questions about the topic.
Knowledge is power. It’s very important for each of us to understand what our options are, and what evidence supports each option. Preventing diseases before they start is often the most efficient way to be healthy, and this starts by screening for the diseases that are appropriate for us depending on age, gender, and other factors. Download our app to go through a short list of questions, and receive a personalized list of the appropriate screening recommendations for you. More information about each of these tests is provided through the app, so that you can stay informed and educated.
Here are a few studies (including those mentioned above) which give insight into the efficacy of screening and early treatment for lung cancer. Feel free to contact us for more information about the matter, we would be happy to provide more information.
Pinsky PF, Church TR, Izmirlian G, Kramer BS. The National Lung Screening Trial: results stratified by demographics, smoking history, and lung cancer histology. Cancer. 2013.
Aberle DR, Adams AM, Berg CD, Black WC, Clapp JD, Fagerstrom RM, et al.; National Lung Screening Trial Research Team. Reduced lung-cancer mortality with low-dose computed tomographic screening. New Engl J Med. 2011;365(5):395-409.
Infante M, Lutman FR, Cavuto S, Brambilla G, Chiesa G, Passera E, et al; DANTE Study Group. Lung cancer screening with spiral CT: baseline results of the randomized DANTE trial. Lung Cancer. 2008;59(3):355-63.
Saghir Z, Dirksen A, Ashraf H, Bach KS, Brodersen J, Clementsen PF, et al. CT screening for lung cancer brings forward early disease. The randomised Danish Lung Cancer Screening Trial: status after five annual screening rounds with low-dose CT. Thorax. 2012;67(4):296-301.