Why should we want to screen? Survival (years) Goldstraw et al. J Thorac Oncol 2007 Why should we want to screen? Localised Stage shift ! Regional spread Distant spread When diagnosis is based on symptoms When diagnosis is based on screening National lung screening trial (NLST) Inclusion criteria - Age 55-74 years - Smoking history ≥30PY, active or stopped less than 15 years ago Exclusion criteria - History of lung cancer Other prior cancer in past 5 years Chest CT less than 18 months ago Unexplained weight loss (>15lb in past year) Metallic implants or devices in chest or back Home oxygen supplementation Pneumonia treated with antibiotics in past 12 weeks Aberle et al. N Engl J Med 2011 National lung screening trial (NLST) - 53’454 subjects randomised to one of two groups: - Low dose CT - Chest X-ray - 3 screening rounds at annual intervals - Non-calcified nodules ≥4mm in CT or any size in X-ray were referred for diagnostic work-up - Primary outcome: lung cancer related mortality Aberle et al. N Engl J Med 2011 National lung screening trial (NLST) Aberle et al. N Engl J Med 2011 National lung screening trial (NLST) Aberle et al. N Engl J Med 2011 National lung screening trial (NLST) Kovalchik et al. N Engl J Med 2013 National lung screening trial (NLST) Kovalchik et al. N Engl J Med 2013 Lung cancer screening trials Boiselle, JAMA 2013 Screening recommendations Boiselle, JAMA 2013 Open issues - Is one positive trial enough evidence? - Was there overdiagnosis in the NSLT? - Will other populations at risk of lung cancer benefit from CT screening? - Screening of a large, at-risk population possible? - How many screening rounds? - Cost effectiveness? - «side effects» of screening (i.e.radiation exposure) Conclusions Lung cancer is a lethal disease associated with substantial medical and economic burden. NLST: lung cancer screening may reduce mortality considerably. Possible advantage of LDCT screening has to be balanced against the potential of inducing harm. Many issues are not yet resolved: i.e. overdiagnosis, number of screening rounds, study population, cost-efficacy. Further evidence and information is needed, before lung cancer screening can be recommended in Switzerland.