Histopathology showed moderate hyperkeratosis and rete ridge elongation with the epidermal thinning above the papillar layer and a few melanophages in the dermis.
Exodermis An outermost layer of thickened or suberized cortical cells that sometimes replaces the epidermal layer in the older parts of roots if the epidermal cells have died.
Some breast cancers also have mutations in the ERBB2 gene that increase human epidermal growth factor receptor 2, or HER-2, which when activated, promotes the growth of cells.
Initially, ink is deposited into the epidermis as well, but as the skin heals, the damaged epidermal cells are shed and replaced by new, dye-free cells with the topmost layer peeling off like heeling sunburn.