In a population screening, a large group of people is examined for the presence of a disease. Importantly, it can have large benefits for a small group but also smaller negative consequences for a larger group. Important advantages are: fewer deaths from lung cancer and that more treatments are less invasive. But screening also has disadvantages, such as the exposure to a low dose of X-ray radiation through the CT scans. Participation can also cause fear/uncertainty while scanning and waiting for the results. It is also possible that an abnormality is seen, but that after additional examinations it turns that it is in fact not lung cancer (false positive result). It is very important that the benefits clearly outweigh the harms: we call this the benefit-risk ratio. This is also stated in the Dutch Population Screening Act.
It is important that we know who has a (high) risk of the disease. Smoking behavior is an important part of determining lung cancer risk. Around 80-90% of lung cancers are related to smoking history. Importantly, at least half of the people with a high risk have already stopped smoking. However, the risk remains high for a long time, even after quitting smoking. Factors such as secondhand smoke (passive smoking) and air pollution/chemical substances increase the risk of lung cancer. These factors can be taken into account in the coming analyses and once there is more clarity about these various factors, they will certainly be included in the selection criteria. Until then, it is important to be alert to complaints that may indicate lung cancer if people were exposed to long-term secondhand smoke or polluted air.