laagdosisCTscreening

Laagdosis-CT screening, also called LDCT screening, is a medical screening method that uses low-dose computed tomography to detect lung cancer at an early stage in people without symptoms but who are at high risk.

Typical eligibility includes age and smoking history; guidelines commonly recommend adults roughly 50–80 years old with at least 20 pack-years of smoking history who currently smoke or quit within the past 15 years; exact criteria differ by country.

Evidence from large trials shows mortality reductions. The US NLST trial (2002-2009) found a reduction in lung cancer mortality by about 20% with LDCT compared with chest radiography. The European NELSON trial reported up to around 26% mortality reduction. Benefits must be weighed against harms such as false positives, overdiagnosis, and radiation exposure.

Screening process typically involves annual LDCT; radiology uses standardized reporting like Lung-RADS to categorize findings and guide follow-up. Positive results may trigger repeat imaging or procedures; surveillance intervals vary, and incidental findings are possible.

Implementation and status vary by country. In the United States, guidelines generally recommend LDCT for adults 50–80 with a 20 pack-year history who currently smoke or quit within the past 15 years. In Europe, several countries have piloted LDCT programs; smoking cessation remains an essential component of any screening strategy.