Bronchioloalveolar carcinoma (PAS stain)

Bronchioloalveolar carcinoma (PAS stain) • This is a periodic acid Schiff (PAS) stain which highlights mucins, among other structures. • The yellow arrows point to the red purple staining of mucin droplets within the neoplastic cells. • Although most bronchioloalveolar cells have some mucin staining, some exhibit extensive staining and show Clara cell differentiation. • This neoplasm shows scattered positive cells. (Description By:Melinda Sanders, M.D. ) (Image Contrib. by: UCHC )