Pilomatrixoma : Histology

At low magnification, pilomatrixoma has a biphasic appearance consisting of solid blue areas of basaloid cells and eosinophilic areas of ghost cells. Basaloid component predominates in early lesions where as ghost cells make up the bulk of mature lesions. There is usually a sharp demarcation between the two components due to abrupt keratinization of basaloid cells into ghost and shadow cells.