pilomatricoma MPATH:571 Tumor composed of the epithelial components of the most proximal (trichogenic) portion of the hair follicle associated with an aberrent hair cortex type of cornification (ghost cells or shadow cells). The most primitive cellular component consists of basophilic cells having scanty cytoplasm and nuclei that occasionally overlap to some extent. In humans mineralisation is common. mouse_pathology.ontology basaloid follicular neoplasms