Baseline and second round results from the population based Dutch-Belgian randomized lung cancer screening trial (NELSON)

1508 Background: Early lung cancer detection with X-ray was unable to reduce lung cancer mortality. Low-dose spiral CT screening cohort studies have demonstrated that lung cancer can be detected at an early stage in a high percentage. Unknown is whether spiral CT screening will lead to a lung cancer mortality reduction and if lung cancer screening will be cost-effective. These questions will be addressed in the randomized Dutch-Belgian-Danish lung cancer screening trial (NELSON) of 20,000 participants. Methods: To identify high-risk subjects a health questionnaire was sent to 600,000 men and women aged 50–74 in seven Dutch public health districts and 14 municipalities in Belgium. Current and former smokers (quit < 10 years) who smoked at least 16 cigarettes a day for at least 26 years or at least 11 cigarettes a day for at least 31 years were invited. After receiving informed consent, participants were randomized between screen-arm and control-arm (usual care). CT scans are performed with 16-detector multi-slice Spiral CT scanners and Siemens Lungcare workstations and software for volumetric analyses in all 4 screening sites. The Lungcare radiological data are automatically uploaded in the NELSON Management System (NMS). Results and Conclusions: In the Netherlands and Belgium, 15,822 subjects have been randomized (1:1) and have undergone baseline and 2nd round sceening one year later. Of them, 83% was male and 17% female, 56% current smoker and 44% former smoker. The majority of current (n=1558) and former (n=1355) smokers had a smoking history of 30–39 PY. Of the former smokers, 62% had quit < 6 yrs and 36% between 6–10 yrs. In total 13,081 nodules have been detected at baseline. Of them, 66% were benign or < 50 mm3 and needed no further evaluation, 30% was indeterminate and 4% was larger than 500 mm3 and required further work-up and evaluation. Data on detection rates, disease stage volume doubling times and natural history of individual nodules after 2 years of follow-up will be presented at the meeting. No significant financial relationships to disclose.