Also known as: Sclerosing Spitz nevus, desmoplastic nevus

Clinical Features:

• Most common on the extremities of adults
• Presents as a dome-shaped papule or nodule

Histologic Features:

• Ill-defined proliferation of large polygonal to spindled melanocytes within a fibrotic dermis, most often with no junctional component
• The melanocytes often show nesting in the more superficial aspects of the lesion and infiltrate as single cells between the thickened dermal collagen bundles in the deeper aspects (maturation).
• The melanocytes also tend to become smaller as they go deeper into the dermis.
• Occasional multinucleated giant cells and pleomorphic cells may be present, especially in the upper portions of the lesion.
• Mitoses are absent or very rare.

Cases associated with this book:

Desmoplastic Spitz nevus
Author: Stephen Lyle, M.D., Ph.D.

Conference: Dermpedia Teaching Collection