As a radiologist, I would like to congratulate the authors of the article “Lung Cancer Screening with Low-Dose Computed Tomography after the National Lung Screening Trial. The Debate is Still Open” for their comprehensive review of this topical controversial issue, and to express my agreement with most of their arguments, particularly with regard to the idea that an early lung cancer detection program with low-dose computed tomography (LDCT) should be studied as part of a structured and multidisciplinary process.1

There are, however, some inconsistencies between the title of the article, which appears to recognize the landmark represented by the National Lung Screening Trial (NLST) and the recommendations made by the authors based on the heterogeneous characteristics and varying results of the different lung cancer screening programs carried out to date. Some of the data reported by the authors (referring to radiation exposure or the LDCT slice thickness, for example) which they appear to use as the basis of some of their recommendations are questionable, or at least, more typical of the earliest screening studies and unacceptable according to the standards established by the NLST.2–5 With regard to the economic impact, there are preliminary data suggesting that an early lung cancer detection program with LDCT would not only cost less than other widely accepted cancer screening programs (cervical, breast), but that in comparison with these other cancers, the cost per life-year saved would also be more favorable.6,7

As the first randomized clinical trial to show a reduction in lung cancer-specific mortality of 20.3% in a high-risk population, the design and results of the NLST represent a turning point. Although there are still questions to be answered and areas for improvement, the principal conclusion of the NLST is that LDCT screening in a certain risk group reduces lung cancer mortality. Most previous clinical trials (with suboptimal designs and smaller study populations) have shown that LDCT is a useful diagnostic tool for the early detection of lung tumors in subjects at risk, but these studies lack the consistency and quality of the NLST. Accordingly, I believe that the real point of departure for making updated recommendations for a hypothetical lung cancer screening program must be the NLST.

The authors’ comment saying “…we do not recommend lung cancer screening with CT for smokers or ex-smokers outside of the context of individual counseling” is not consistent with the primary conclusion of the NLST (the reduction of lung cancer-specific mortality with LDCT screening in a specific risk group), particularly when the title of the article appears to recognize the importance of this trial. Indeed, what the NLST has come to show (and its results have been quickly translated into the clinical practice guidelines of several American scientific societies) is that LDCT screening of a specific risk group reduces lung cancer mortality, and so could be implemented within a structured, multidisciplinary program guaranteeing comparable results.4 The professionals involved (and the selected participants) must be aware of the potential risks and benefits of a screening program of these characteristics, but in the end it will be the participant who decides to use the program or not.

The recommendation of the authors to “unite our efforts to make sure that healthcare professionals are alerted to lung cancer symptoms, while improving their training and making smokers aware of the risk they have for developing lung cancer” is insufficient if the aim is to achieve early detection of this disease and reduce mortality. In some countries there are already more ex-smokers than active smokers who meet NLST criteria, so excluding the growing population who have quit smoking but who still have an increased risk of developing lung cancer does not seem to be a very advisable measure.

The debate is not only still open, but must remain open and receptive to the scientific evidence and opinions that will ultimately determine whether LDCT has a significant role in the early detection of lung cancer.