Clear cell acanthoma

    Article Contributors: 
    Sean Klepper M.D.
    Artur Zembowicz M.D....

    Clinical Features:

    • Red papule or plaque on the lower extremities of middle-aged to elderly individuals

    Histologic Features:

    • Psoriasiform hyperplasia of the epidermis with fusion of the rete ridges
    • Proliferation of pale ("clear") keratinocytes (polyhedral and larger than normal keratinocytes), sharply demarcated from the adjacent normal epidermis
    • The clear cells are PAS positive, diastase sensitive (glycogen).
    • Neutrophils may infiltrate the epidermis, sometimes forming microabscesses in the stratum corneum.
    • Parakeratosis and crusting may be seen.
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    Cases associated with this book:

  • Clear cell acanthoma
    Author: Artur Zembowicz M.D. Ph.D.

    Conference: Teaching Collection