Lung Cancer: Annual CT Screening for High Risk Patients Interview with:
Harry J de Koning, MD PhD
Professor of Public Health & Screening Evaluation
Rotterdam, The Netherlands. What are the main findings of the study?

Dr. de Koning: Annual CT screening for lung cancer has a favorable benefit-to-harm ratio for individuals ages 55 through 80 years with 30 or more pack-years’ exposure to smoking. It would lead to 50% (model ranges, 45% to 54) of cases of cancer being detected at an early stage (stage I/II), 575 screenings examinations per lung cancer death averted, a 14% (range, 8.2% to 23.5%) reduction in lung cancer mortality, 497 lung cancer deaths averted, and 5250 life-years gained per the 100 000-member (1950-) cohort. Harms would include 67 550 false-positive test results, 910 biopsies or surgeries for benign lesions, and 190 overdiagnosed cases of cancer (3.7% of all cases of lung cancer [model ranges, 1.4% to 8.3%]), again for a 100 000-member (1950-) cohort. Were any of the findings unexpected?

Dr. de Koning: Yes and no; the NLST (National Lung Screening Trial) had shown benefits from 3 annual CT screens in a specific volunteer population aged 55-74.

Inviting asymptomatic individuals for screening and implementing a large-scale screening program should be considered only when the benefits clearly outweigh the harms. Our analysis provides a detailed account of the balance between harms and benefits of annual lung cancer screening to inform individuals, clinicians, and policymakers. This analysis estimated life-time benefits and harms of different screening scenarios, and found a set of efficient scenarios, that included continuing screening through age 80. It estimated life-years gained, but also important harms like over diagnosis, false positives and radiation-related lung cancer deaths, that was not available yet. What should clinicians and patients take away from your report?

Dr. de Koning: First of all, to try to stop smoking and discourage starting smoking.

Secondly, the USPSTF recommends, partly based on our results, yearly screening with LDCT in adults aged 55 through 80 years who have at least a 30 pack-year history of smoking and who continue to smoke or who have quit less than 15 years ago.

Thirdly, I think it is important to realize that over diagnosis in lung cancer screening is relatively limited. What recommendations do you have for future research as a result of this study?

Dr. de Koning: The NEderlands-Leuven Screening Onderzoek (NELSON) trial, which enrolled 15 822 individuals age 50 to 75 years and compared CT screening with no screening in Europe is still missing mortality results. But, the NELSON trial has primarily used volume-doubling times and volume measurements of lung nodules to define its referral strategy, thereby substantially reducing the number of positive and false-positive results: About 60% of referrals were for false-positive results, and the percentage of referrals was about 2%. It may therefore be feasible to reduce one of the important harms of lung cancer screening via changes in follow-up guidelines.

In the coming years it may also be possible to improve eligibility criteria for screening and adapt our models to incorporate broader eligibility criteria based on more complex measures of risk.


Harry J. de Koning, Rafael Meza, Sylvia K. Plevritis, Kevin ten Haaf, Vidit N. Munshi, Jihyoun Jeon, Saadet Ayca Erdogan, Chung Yin Kong, Summer S. Han, Joost van Rosmalen, Sung Eun Choi, Paul F. Pinsky, Amy Berrington de Gonzalez, Christine D.