Deep penetrating nevus

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

    Clinical Features:

    • Peak incidence between 10 and 30 years of age
    • Most common on the face, upper trunk and proximal extremities
    • Presents as small, raised bluish lesion mimicking blue nevus

    Histologic Features:

    • Well-circumscribed, symmetric lesion within the dermis, sometimes also displaying a junctional component
    • The architecture is that of a wedge-shaped proliferation of tightly packed, pigmented spindle cells
    • The spindle cells show a diffuse arrangement in the upper dermis, and become arranged into discreet fascicles as they move into the deep dermis
    • The spindle fascicles may have a bulbous contour in the deeper aspects of the lesion, and may extend into the subcutaneous fat.
    • The nevus cells are often closely associated with neurovascular and adnexal structures in the deeper dermis.
    • Melanophages are often present in association with the nevus cells.
    • Focal significant cytologic atypia is often present, and occasional mitoses (1 to 2 per square millimeter) may be seen.
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    Cases associated with this book:

  • Deep penetrating nevus
    Author: Stephen Lyle, M.D., Ph.D.

    Conference: Dermpedia Teaching Collection