Angiofibroma

What is an angiofibroma?

A cutaneous angiofibroma is a benign vascular neoplasm composed of dermal fibrous tissue and blood vessels.

Angiofibroma is classified by association with a genetic disorder or according to its body site [1].

Who gets angiofibromas?

Angiofibromas are associated with the following genetic disorders:

• Tuberous sclerosis
• Birt-Hogg-Dubé syndrome
• Multiple endocrine neoplasia type 1 (MEN-1).

Angiofibromas are more commonly acquired.

Tuberous sclerosis

Tuberous sclerosis is a neurocutaneous autosomal dominant syndrome, in which angiofibromas appear in childhood in the nasolabial folds and on the central face [2]. Patients with tuberous sclerosis commonly develop an oral fibroma or a periungal angiofibroma (Koenen tumour) over time [1]. The facial angiofibromas associated with tuberous sclerosis are also called adenoma sebaceum, juvenile angiofibroma, and Pringle tumour.

Angiofibromas in tuberous sclerosis 

Angiofibromas in tuberous sclerosis 

Angiofibromas in tuberous sclerosis 

Birt-Hogg-Dubé syndrome

Facial angiofibromas have been reported in Birt-Hogg-Dubé syndrome, a rare genodermatosis characterised by skin and renal tumours, as well as spontaneous pneumothorax [3]. Most of the cutaneous lesions however are fibrofolliculomas, which are abnormal growths of the hair follicles.

Multiple endocrine neoplasia type 1

Multiple endocrine neoplasia type 1 is a hereditary syndrome that leads to tumours in several endocrine organs [1].

Acquired angiofibroma

Angiofibromas can also be acquired and unrelated to a genetic syndrome, commonly in the form of:

• Fibrous papule of the nose/face
• Pearly penile papules.

A fibrous papule is characteristically found in adults as a solitary lesion usually on the nose, often clinically mistaken for a basal cell carcinoma or melanocytic naevus. It is thought to be a form of dermal naevus.

Multiple pearly penile papules occur in 10–30% of adult males on the coronal edge and sulcus. They can be mistaken for viral warts [1,2].

Fibrous papule 

Fibrous papule of the nose 

Fibrous papule of the nose 

See penile pearly papules images.

What causes angiofibromas?

Angiofibromas are caused by a local overgrowth of collagen, fibroblasts, and blood vessels.

• In tuberous sclerosis, mutations are present in tuberous sclerosis complex 1 (TSC1), which encodes the protein hamartin, and tuberous sclerosis complex 2 (TSC2) which encodes the protein tuberin.
• Birt-Hogg-Dubé syndrome is due to a mutated FLCN gene, which encodes the protein folliculin [3].
• Multiple endocrine neoplasia type 1 results from a mutation in the MEN1 gene which produces the protein menin [1].

Genetic mosaicism for these genetic conditions must also be considered [4]. What specifically triggers the development of angiofibroma is unknown.

What are the clinical features of angiofibroma?

An angiofibroma is a firm, flesh-coloured dome-shaped papule less than 5 mm in diameter. Small capillaries may be visible on the surface of the lesion.

• Facial angiomas associated with a genetic syndrome are commonly found in clusters in the butterfly region of the face.
• A fibrous papule of the face is usually a solitary lesion located on the nose in an adult.
• Pearly penile papules are 1–3 mm skin coloured or white papules in a row along the penile coronal margin [5].

What are the complications of angiofibromas?

Angiofibromas may be itchy and may also bleed. Those associated with genetic syndromes result in facial disfigurement and stigmatisation [1]. See Psychosocial factors in dermatology.

How are angiofibromas diagnosed?

The diagnosis of angiofibroma may be made clinically or after a skin biopsy. The histopathology of angiofibroma shows an ‘onion skin’ pattern around vessels and follicles, hyperkeratosis, and vascular proliferation [5].

If an underlying genetic condition is suspected, appropriate genetic screening and evaluation are required [1].

What is the differential diagnosis for angiofibromas?

The differential diagnosis for angiofibroma depends on its location [1].

Differential diagnoses for facial lesions that can resemble angiofibromas can include:

• Intradermal melanocytic naevus
• Acne
• Basal cell carcinoma

Differential diagnoses for periungual lesions that can resemble angiofibroma can include:

• Viral warts
• Subungual exostosis.

Differential diagnoses for penile lesions that can resemble angiofibroma can include:

• Molluscum contagiosum
• Anogenital warts.

What is the treatment for angiofibroma?

Angiofibromas are benign and do not always require removal. Options for treatment of angiofibromas include:

• Excision
• Dermabrasion
• Using lasers, electrical, and radiofrequency devices
• Cryotherapy
• Topical podophyllotoxin
• Topical rapamycin
• Topical beta-blocker (eg, timolol) [6].

Multiple treatments are often necessary [1].

What is the outcome for angiofibromas?

Although angiofibromas are benign, they are persistent. Angiofibromas can be removed for cosmetic or pain-related reasons. The recurrence rate for angiofibromas associated with tuberous sclerosis may be as high as 80% [1].