[Lung cancer screening: status in 2007]

Area of Science:

• Oncology
• Radiology
• Pulmonology

Background:

• Lung cancer has a poor prognosis when diagnosed symptomatically ( <15% 5-year survival).
• Early detection in asymptomatic individuals dramatically improves prognosis (up to 80% 5-year survival).
• Risk factors and high sensitivity of low-dose CT for small tumors support screening.

Purpose of the Study:

• To evaluate the potential of lung cancer screening for early detection and improved patient outcomes.
• To assess the feasibility of diagnostic algorithms for managing detected pulmonary nodules.
• To identify potential biases that may affect mortality reduction.

Main Methods:

• Review of feasibility studies utilizing diagnostic algorithms for pulmonary nodules.
• Analysis of low-dose computed tomography (CT) for detecting small tumors.
• Consideration of potential biases including overdiagnosis and lead-time bias.

Main Results:

• Feasibility studies show high detection rates (>50-90%) of early-stage, resectable non-small-cell lung cancer.
• Early-stage detection is associated with good prognosis and low rates of unnecessary biopsies.
• Potential biases require further investigation through large prospective trials.

Conclusions:

• Lung cancer screening, particularly with low-dose CT, offers a significant survival advantage through early detection.
• While promising, potential biases necessitate cautious interpretation and await results from large-scale randomized trials.
• Ongoing research into alternative early diagnostic methods like sputum analysis and molecular markers continues.