Lung adenomatous hyperplasia to carcinoma The development of CT high-resolution scans has allowed us to diagnose small GGO lesions in the lung. The management of these lesions is still controversial. There is an adenoma to carcinoma hypothesis that ranges from a continuous sequence of precancerous lesions to adenocarcinoma progression in the coexistence of lung lesions representing very early stage adenocarcinoma. In clinical experience, the incidence of GGO was 2.8%, but in the elderly group it was 6.6%. In addition, these GGOs occur more frequently in cancer patients, especially in lung cancer patients, with an approximate incidence of 10-23.2%. It has been suggested that they are very rare in asymptomatic individuals, with an incidence of about 0.05%. This difference can be explained by the fact that GGO can only be detected by CT, but in fact, some scholars believe that GGO can be detected by HRCT. Some scholars believe that a persistent SPN (isolated pulmonary nodule) with a GGO larger than 10 mm must be cancer, but others have documented that some AAH are also larger than 10 mm and not all are tumors, so the size of the lesion cannot be used as a diagnostic criterion. CT findings and pathological features of AAH: CT examinations of AAH lesions are as follows: a multiplicity; b location of the lesion; c shape; d size and internal density; e interface between the lesion area and normal lung; f internal features of the lesion; and g changes in the lesion. Lesion size and internal density were measured in the largest lesion area. We used follow-up CT to detect any changes in the lesion. Patients had an average of 2.25 CT examinations with an interval of 33-540 days, with a mean of 145.3 days.