Fig. 2From: Multiple bronchiolar adenomas with malignant transformation and CCNE1 mutation: a case report and literature reviewPathological findings of pure GGN in the lingual segment of the left upper lobe. a Alveoli with single or double layers of columnar epithelial cells or flat cells (hematoxylin and eosin stain, magnification 400 ×). b, c and d immunohistochemical staining showed positive for TTF-1 and P63 (focal) and negative for CK5/6 (magnification 400 ×)Back to article page