Skin - Nonmelanocytic tumors
Other tumors of skin
Angiofibroma

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

Revised: 21 September 2016, last major update September 2016

Copyright: (c) 2002-2016, PathologyOutlines.com, Inc.

PubMed Search: Angiofibroma [title]

See also: Soft tissue - cellular angiofibroma

Definition / General
  • Also known as fibrous papule
  • Common benign fibrohistiocytic tumor, usually on the face of middle aged persons and often on the nose
  • Some have postulated this lesion to be a hamartoma composed of perifollicular or interfollicular connective tissue and a hair follicular epithelial component (J Cutan Pathol 2009;36:943)
  • May be a reactive, proliferative process derived from dermal dendrocytes
Clinical Features
  • Asymptomatic, red to skin colored, dome shaped, firm papule
  • Usually on the nose or central face; often solitary
  • Generally small, 3 - 5 mm
  • Multiple angiofibromas can be seen in genetic syndromes such as neurofibromatosis 2, Birt-Hogg-DubĂ©, multiple endocrine neoplasia type 1 (MEN1), and tuberous sclerosis (TS is associated with multiple angiofibromas termed adenoma sebaceum on the central face at puberty)
Clinical Images

Images hosted on other servers:

Various images

Micro Description
  • Slightly raised and well circumscribed dermal lesion composed of collagenous stroma with increased spindled to stellate fibroblasts and increased and dilated blood vessels
  • Collagenous stroma consists of collagenous alteration with concentric orientation around hair follicles or blood vessels or perpendicular orientation to epidermis
  • Multinucleated fibroblasts are often present, and scattered dermal melanophages may be present
  • Mitotic figures are rare
  • Epidermis uninvolved but can appear often flattened or atrophic
  • Scattered vellus hairs may be present
  • Patchy epidermal melanocytic hyperplasia is often found, sometimes slight hyperkeratosis is seen

  • Many histologic variants have been described that can make the diagnosis challenging:
    • Hypercellular: has a marked increased in fibroblasts
    • Clear cell: proliferation of clear to slightly foamy cells
    • Pigmented: prominent basal melanocytic hyperplasia and dermal melanophages
    • Pleomorphic: prominent bizarre stellated pleomorphic cells
    • Granular: proliferation of cells with granular cytoplasm
Micro Images

Images hosted on PathOut servers:

Courtesy of Hillary Rose Elwood, M.D.



30 year old man with nose lesion, courtesy of Drs. Asmaa Gaber Abdou and Nancy Asaad



Images hosted on other servers:

Various images

Immunohistochemistry
  • Not necessary for diagnosis but may help exclude entities in the differential diagnosis
  • Spindled and stellate cells should be positive for Factor XIIIa and negative for cytokeratins and S100 (the latter helps to exclude a melanocytic proliferation)
  • Spindled and stellate cells can also be positive for CD68 and CD34
  • NKI-C3 expression has also been described, particularly in clear cell variants
Differential Diagnosis
  • Angiofibromas of tuberous sclerosis (Adenoma sebaceum): appear identical; if you have multiple biopsies from the central face of a child that morphologically look like fibrous papules, might be worth mentioning the possibility of tuberous sclerosis
    • Subtle differences have been described to distinguish adenoma sebaceum (e.g. fibrous papules are said to have more ectatic blood vessels, more numerous stellate cells and more prominent basal melanocytic hyperplasia with less prominent concentric perivascular fibrosis)
  • Angioma: dilated increased vessels but no stellate cells or cellular stroma
  • Fibrofolliculoma and trichodiscoma
  • Fibrosing / sclerotic melanocytic nevus: lacks the stellate cells or cellular stroma, S100+
  • Pearly penile papules: identical histologic features except on the penis and no hair follicles
  • Pleomorphic fibroma: pleomorphic fibrous papules can show overlapping histologic features with pleomorphic fibroma; however, pleomorphic fibromas are typically larger and more commonly located on trunk or extremities
  • Scar
Additional References