Clinical Features:

• One- to three-millimeter pigmented cysts presenting most commonly on the chest, abdomen or extremities
• Single, sporadic lesions usually present in the first two decades of life.
• Multiple lesions represent an autosomal dominant disorder known as eruptive vellus hair cysts.  These present at a younger age and can be associated with other cutaneous lesions (steatocystoma multiplex, trichostasis spinulosa, pachyonychia congenita) and neurologic disorders.

Histologic Features:

• Dermal cyst lined by squamous epithelium with an attenuated granular layer
• The cyst contains vellus hair shafts and lamellated keratin
• The cyst wall sometimes contains telogen-like hair follicles.

Cases associated with this book:

Vellus hair cyst
Author: Artur Zembowicz M.D. Ph.D.

Conference: DermatopathologyConsultations.com Teaching Collection