Anatomy of the Skin

  • Three layers
    • Epidermis
      • Avascular
      • Stratified squamous cells
      • Thickness varies
        • 0.05 mm (eyelids) to 0.15 mm (palms and soles)
      • Surface cells are chronically shed and replaced by mitotic cells from the basal layer
        • As cells migrate from basal to outer epidermis, they lose their nuclei and ability to replicate
    • Dermis
      • Thickness: 1-2mm
      • Papillary layer adjacent to the epidermis basement membrane and a deeper reticular layer
      • Connective tissue stroma of collagen and elastin fibers gives the skin structural integrity
      • Contains:
        • Nerves
        • Blood and lymphatic vessels
        • Adnexal structures
    • Subcutis
      • Most variable thickness and contains connective tissue and fat supporting larger nerves and vessels

Epidemiology and Etiology of Skin Cancer