Pulmonary nodular proliferative foci are nodular shadows of higher density found in the lungs on chest CT examination, which are fibrous scar tissue turned into by the maturation of granules repairing necrotic tissue during the inflammatory process. 1. Proliferative foci: In the process of inflammation, in order to repair the damaged tissue, the surrounding naïve connective tissue proliferates to form granulomatous red granular soft tissue, which contains a large number of newborn capillaries and newly born fibroblasts and a certain number of inflammatory cells, which dissolves and absorbs the foreign matter and fills the defect, and the granulomatous tissue then matures gradually to transform into scar tissue. 2. Lung infections, tuberculosis, smoking, etc. can cause pulmonary nodular fibroproliferative foci. 3. Lung nodular proliferative foci are generally benign lesions that do not require treatment. Only a very small number of larger scars may develop scar cancer, which usually only requires regular review. The presence of pulmonary nodular proliferative foci suggests further consultation in the hospital.