Lichenoid keratosis

    Article Contributors: 
    Sean Klepper M.D.
    Stephen Lyle, M.D., ...

    Also known as: lichen planus-like keratosis, solitary lichen planus

    Clinical Features:

    • Most common in middle aged white individuals, with a female predominance
    • Usually of short duration
    • Most often presents as a solitary, sharply demarcated papule or plaque, with a predilection, for the face, neck, upper trunk and distal upper extremity
    • Often misdiagnosed clinically as a seborrheic wart, superficial BCC or acitinic keratosis

    Histologic Features:

    • The findings are quite similar to those of lichen planus:
      • Hyperkeratosis, often with focal parakeratosis
      • Hypergranulosis
      • Variable acanthosis
      • Basal cell vacuolar change
      • Often exocytosis of lymphocytes
      • Epidermal and dermal colloid bodies
      • Pigment incontinence
    • The saw-tooth rete ridge pattern typically of lichen planus is sometimes seen, but lichenoid keratosis more frequently shows broadened, irregular rete ridges.
    • There is most often a dense lichenoid lymphohistiocytic infiltrate, as in lichen planus; however, occasionally the infiltrate in lichenoid keratosis is mainly perivascular.  Focal plasma cells and eosinophils may also be present.
    • The basal layer may show reactive atypia.
    • Immunofluorescence shows staining for IgM and sometimes IgG, as in lichen planus.
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    Cases associated with this book:

  • Lichenoid keratosis
    Author: Stephen Lyle, M.D., Ph.D.

    Conference: DermatopathologyConsultations.com Teaching Collection