Lung-RADS using low-dose CT (LDCT) lung cancer screening

Lung-RADS (Lung Imaging Reporting and Data System) is a standardized classification system developed by the American College of Radiology to improve the accuracy and consistency of low-dose CT (LDCT) lung cancer screening. It is primarily used for evaluating lung nodules in high-risk patients undergoing annual screening, such as long-term smokers aged 50 to 80. A key distinguishing factor is this approach is ONLY to be used for asymptomatic patients.  So if a patient has a chronic cough, recent pneumonia, or prior lung cancer, this is NOT the test for them.  The goal of Lung-RADS is to reduce unnecessary follow-ups and biopsies while improving early detection of lung cancer when it is most treatable.

Lung-RADS assigns a category score from 1 to 4X, depending on the size, type (solid or subsolid), and growth of pulmonary nodules seen on LDCT which will be done by the Radiologist interpreting the exam, this is not for the clinician to attempt to categorize. For example, a Lung-RADS 1 or 2 suggests benign findings with no or minimal risk of malignancy, typically requiring annual follow-up. Lung-RADS 3 indicates a moderate risk, often prompting a 6-month follow-up scan, while Lung-RADS 4A, 4B, and 4X reflect higher suspicion for cancer and may require PET-CT, tissue sampling, or referral to a thoracic specialist.

The system improves communication between radiologists, referring providers, and patients by offering clear, actionable follow-up recommendations based on evidence-based risk stratification. This reduces confusion, helps avoid over-treatment of benign nodules, and streamlines care for nodules that may be malignant. By standardizing reports, Lung-RADS also makes data collection for research and quality control more efficient across lung screening programs.

Lung-RADS Categories and Risk of Malignancy