Lung cancer screening CT — choose nodule type, then size at baseline. Use the mean of long & short axis.
1 · Category 1?
2 · Nodule type
3 · Size
4 · Modifiers (optional)
4X applies only to Category 3 or 4 nodules and raises management to 4B. S and C may be added to any category and do not change the lung-cancer follow-up.
Start: is it Category 1?
Baseline screening categorization.
ACR Lung-RADS v2022, baseline screen. Apply the 4X, S and C modifiers in step 4 where relevant (new/growing nodules also escalate — see ACR). Sizes are mean diameter. Decision support only — not a substitute for the full criteria or clinical judgment.
American College of Radiology. Lung-RADS v2022. acr.org/Lung-RADS.