Keloid : Microscopic Features
Microscopic Features: Keloids are characterized by proliferation of thick, eosinophilic, hyalinized (glassy) collagen bundles that are haphazardly arranged in the dermis. In the early stages, the lesions are vascular and cellular. They show fibroblasts and myofibroblasts between collagen bundles as well as foci of myxoid matrix. As the lesions mature, they become hypocellular, undergo hyalinization, focal calcification, and even osseous metaplasia. Bland spindle cells are seen between collagen bundles. Normal skin appendages are displaced by the lesion and the overlying epidermis may atrophy. Rare mitoses may be present.