Fibrous papule of the face is a benign, clinically indistinct papule, also known as sporadic angiofibroma.
In the past, fibrous papule has been suggested to have been derived from preexisting or involuting melanocytic nevi; however, subsequent investigations appear to have refuted this and have confirmed a relationship to factor XIIIa – positive dermal dendrocytes. Fibrous papule is best considered a variant of angiofibroma.[1]
A study from 2014 showed expression of antibodies against p-mTOR in dermal stromal cells and epidermal keratinocytes in fibrous papules, similar to tuberous-sclerosis complex–associated facial angiofibromas, suggesting topical rapamycin may be a treatment option.[2]
The condition is relatively common.
No racial predilection is known.
Both sexes are equally affected.
Most of the patients are in their third to fifth decade of life.
Fibrous papule of the face is a benign lesion. Most of the lesions are asymptomatic, although one third of patients have reported bleeding following minor trauma.
The patient should be reassured that the lesion is harmless. Patients should also be made aware that a surgical procedure results in a scar.
The lesions are clinically indistinct. Fibrous papules are usually dome-shaped lesions with a shiny, skin-colored appearance. Occasionally, lesions are sessile, polypoid, or papillomatous. Most of the lesions are firm and indurated. Size usually ranges from 1-5 mm in diameter.
Fibrous papule of the face usually occurs as a single lesion (as shown below), but, occasionally, several lesions may be present. A case of 68-year-old healthy woman with multiple, approximately 100-150, fibrous papules on the face with no apparent underlying genodermatosis or endocrine disorder has been reported.[3]
View Image | Fibrous papule of the nose. Courtesy of San Antonio Uniformed Services Health Education Consortium Dermatology slide files. |
Most lesions are located on the nose and, less commonly, on the cheeks, chin, neck, and, rarely, on the lip or forehead. Similar papules may be present on the fingers or oral mucosa, where they have been described as reactive nodular hyperplasia or giant cell fibroma.
Fibrous papules are characterized by a proliferation of stellate and spindled cells, a fibrotic stroma, and dilated blood vessels. Occasionally, a sparse inflammatory cell infiltrate of lymphocytes is present.
Acanthosis and an increased number of large polygonal melanocytes may be present in the basal layer. Elastic tissue may be markedly diminished or entirely absent.
View Image | Histopathology of a fibrous papule shows focal fibrosis and vascular proliferation in the upper dermis. Courtesy of Dirk Elston, MD. |
Dermal dendritic cells usually stain for factor XIIIa.
Several histological subtypes have been described, which might cause diagnostic difficulties.
Hypercellular fibrous papule is characterized by an increased number of stellate and spindled cells; differential diagnoses include malignant melanoma and atypical fibroxanthoma.[6]
Clear cell fibrous papule shows a proliferation of round clear cells, some with cytoplasm ranging from finely granular to foamy, resembling histiocytes or clear epithelial cells; differential diagnoses include clear cell neoplasm and metastasis.[7] Some authors also differentiate a granular cell fibrous papule, which is similar to the clear cell fibrous papule but seems to contain coarser cytoplasmic granules.[8]
Pleomorphic fibrous papule is characterized by bizarre, stellate fibroblasts; differential diagnosis includes pleomorphic fibroma.
Pigmented fibrous papule demonstrates prominent melanocytic hyperplasia and dermal macrophages; differential diagnoses include nevus and melanoma.
Inflammatory fibrous papule has dense, diffuse dermal infiltrate of predominantly mixed small and large lymphocytes with plasma cells, histiocytes, and rare eosinophils and neutrophils; differential diagnoses include lymphoma, lymphocytic infiltrate, and an infectious process.
More recently, an epithelioid variant has been described.[6] Histopathologically, it consists of epithelioid-type cells with pink cytoplasm, medium-sized nuclei, and, sometimes, prominent nucleoli; differential diagnoses include melanoma, intradermal nevus, Spitz nevus, xanthogranuloma, and dermatofibroma.
The lesion is benign, but it may be removed to confirm the diagnosis or for cosmetic reasons. Surgical procedures include curettage, shave excision, or elliptical excision. Laser treatment with pulsed dye laser, carbon dioxide laser, and potassium-titanyl-phosphate (KTP) laser has been successfully used for the treatment of angiofibromas such as tuberous sclerosis.