1. R2 정명화 D R Baldwin, S W Duffy, N J Wald, R Page, D M Hansell,J K Field Thorax ; April 2011,Vol 66

2.  >33,500 patients died from lung cancer >38, 500 new diagnoses In the UK, 2008  Five-year survival was only 6.5%  Screening is important since detect presymptomatic cancer at a much earlier stage  Early screening : chest radiographs and sputum cytology -> no improved survival rate the first major lung cancer

3.  Randomised controlled trial screening trial utilising low-dose CT (LDCT) in US-NCI -> 20% of reduced mortality  NELSON (Dutche-Belgian randomised trial) uses volumetric analysis of after 10 years of follow-up  Aim: LDCT screening and treatment of early lesions will decrease lung cancer mortality compared with a control group without screening

4. 1.50~75 years of age 2. >5% risk of developing lung cancer in 5 years. By using LLP 3. These high-risk individuals are contacted with a further questionnaire 4. All smokers are provided with smoking cessation advice sheets 5. The recruits are randomised into the CT screen group and no screen group. 1. Subjects who are unable to give consent precluding written informed consent. 2. Co-morbidity which contraindicate either screening or treatment if lung cancer were detected. 3. Technical reasons (eg, weight >200 kg (too heavy for the CT table), unable to lie flat, etc.) 4. CT performed within 1 year of the invitation to be screened.

12.  The category which NELSON trial defined negative in UKLS divided Category 1 and 2.  NELSON investigators found that the 20 lung cancers (0.24%) detected in round 2 were found.  New suppotive marker for lung cancer (e.g biomaker) is needed

13.  UKLS and NELSON with differences in design will provide information about relative cost-effectiveness of a multiple screen and a single screen. The design similarities mean that there will be the facility for joint reporting of the single screen element.