Skin - Nonmelanocytic tumors
Benign nonmelanotic epidermal tumors / tumor-like lesions
Hair follicle nevus

Authors: Hillary R. Elwood, M.D. (see Authors page)

Revised: 20 June 2016, last major update June 2016

Copyright: (c) 2001-2016,, Inc.

PubMed search: hair follicle nevus
Cite this page: Hair follicle nevus . website. Accessed October 28th, 2016.
Definition / General
  • Rare, congenital, hamartomatous proliferation of mature vellus hairs
  • Also known as congenital vellus hamartoma
Clinical Features
  • Usually present at birth or early childhood
  • Solitary skin colored papule, less than 1 cm in greatest dimension
  • Sometimes with hypertrichosis
  • Most commonly on head and neck
  • Rarely multiple or arranged in a linear distribution, following the lines of Blaschko (J Am Acad Dermatol 2002;46:S125)
Case Reports
Micro Description
  • Increased numbers of closely situated mature vellus hair follicles
  • Some are associated with small sebaceous glands or have thickened perifollicular fibrous sheaths
  • Follicles may be located abnormally high within the dermis
  • No cartilage (seen in accessory tragus), central cysts or a central canal (seen in trichofolliculoma)
Differential Diagnosis
  • Accessory tragus: also has increased vellus hairs, but usually has other types of tissue (i.e. mature adipose tissue or cartilage); location around the ear is also helpful
  • Trichofolliculoma: has central cyst or canal; deeper levels may be necessary to find trichofolliculoma in a lesion that resembles hair follicle nevus