• Bronchiectasis
• pulmonary embolism
• tuberculosis

The UK Lung Screen team in their positional statement outlined the issues to be explored by the trial on CT screening for lung cancer.1 Although it seems to be a large, well-planned study, we believe that there are some shortcomings in this study that may undermine its significance. There are several other aspects of CT screening that need to be investigated in order to determine the suitability of the screening and thus guide a national programme. The additional investigation areas may include:

1. Studying the number of unnecessary lung biopsies, invasive procedures and surgeries due to cancer screening and the morbidity and mortality caused by these procedures.

2. The risk of development of radiation-induced malignancy, both in patients undergoing routine yearly screening and in those subjected to serial CT scans for suspicious lesions. Some studies have shown significant risk of development of radiation-induced malignancies.2

3. Smoking abstinence behaviour in people undergoing screening. Concerns have been raised regarding smokers having a negative result on CT screening believing that they can continue smoking without any increased risk of dying from lung cancer.3 Such behaviour can expose them to other potentially fatal smoking-related diseases like chronic obstructive pulmonary disease and other malignancies.

4. Emotional and psychological effects of false positive results, which can significantly impair the life of the individual.

Moreover, investigators are planning to include only those cases with >5% risk of lung cancer according to the Liverpool Lung Project risk model, which will miss the opportunity to study the impact of screening in a low risk group population, and further the Liverpool Lung Project model may not take into account the separate risk factors working in different ethnic populations4 thus making its prediction less reliable in the cosmopolitan UK population where according to the 2001 census >15% of the population is non-white British.5

We hope that the investigators are open to our suggestions and will accept our ideas if they find some relevance in them.