Difficulties encountered managing nodules detected during a computed tomography lung cancer screening program

Area of Science:

• Pulmonology
• Radiology
• Oncology

Background:

• Screening asymptomatic high-risk individuals with low-dose computed tomography (LDCT) aims for early lung cancer detection.
• Balancing diagnostic procedure overuse against delayed cancer diagnosis is a critical challenge in population screening.
• The Cosmos trial evaluated management of lung nodules found during LDCT screening.

Purpose of the Study:

• To identify pitfalls, difficulties, and sources of error in managing lung nodules detected via LDCT screening.
• To assess the effectiveness and challenges of LDCT screening protocols in a real-world setting.
• To evaluate the role of imaging modalities like positron emission tomography in nodule characterization.

Main Methods:

• 5201 asymptomatic high-risk volunteers underwent LDCT screening.
• Nodule follow-up protocols included repeat LDCT or fluorodeoxyglucose-positron emission tomography (FDG-PET) based on size.
• Growing nodules were managed with further imaging or surgical biopsy guided by growth rate and nodule characteristics.

Main Results:

• 91 lung cancers were identified in the first year, with 70% at stage I.
• Delayed diagnosis occurred in 6 patients (false-negatives), including small cell and central lung cancers.
• Surgical biopsy revealed benign disease in 15 cases (false-positives); FDG-PET sensitivity varied by screening year.

Conclusions:

• LDCT screening is effective for early lung cancer detection, but nodule management requires careful consideration.
• FDG-PET is valuable at baseline but shows reduced sensitivity for interval cancers.
• Multidisciplinary team management and radiologist experience are essential to minimize misdiagnoses and optimize patient outcomes.