DefinitionThis section has been translated automatically.
Frequent, solitary or multiple, completely harmless, 0.3-1.5 cm large, tumour-like, brownish, reactive connective tissue proliferation, which often occurs after an insect bite and is characterised by a "surprising" firmness.
ClassificationThis section has been translated automatically.
According to histological criteria, the following variants have been described in the past:
- neurothekeoma, cellular
- Dermatofibroma with monster cells
- Dermatofibroma, xanthomatized
- Dermatofibroma, hemosiderin storing
- Dermatofibroma with granular cells
- Epithelial cell histiocytoma
- Dermatofibroma, ossifying
- dermatofibroma, myxoides
- Dermatofibroma, desmoplastic
- Dermatofibroma, sclerotic
- Dermatofibroma, deep infiltrating (deep dermatofibroma)
- Dermatofibroma in the facial area
- Aneurysmal dermatofibroma (characterized by rapid growth, high (20%) local recurrence rate after excision)
- Cell-rich dermatofibroma (more frequent in young men in the lower extremities; local recurrence rate is increased (25%) Rare metastases.
- Atypical (pseuodsarcomatous) dermatofibroma (more common on the extremities, also on the head and neck. The term is sometimes used synonymously with Fasciitis nodularis pseudosarcomatosa.
- Metastatic dermatofibroma
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Occurrence/EpidemiologyThis section has been translated automatically.
Prevalence not known; in larger dermatological collectives > 60% of patients. f>m;
EtiopathogenesisThis section has been translated automatically.
The nosological position of the dermatofibroma is currently still controversial.
Anamnestic evidence of (previous) insect bites, folliculitis, micro-traumas, localization (lower leg) and limited growth, show the changes as reactive proliferations (as "organged inflammations").
Controversial are immunohistological findings (expression of MS-I-HMWP), which indicate the dermal dendritic cell as the original population of the tumor and thus bring these "tumors" close to cutaneous non-Langerhans cell histiocytosis.
Furthermore, clonal cytogenetic alterations have been detected, which indicate that the proliferations are "true neoplasias". This thesis is supported by the tendency of some variants to local recurrence. Occasionally (extreme rarity) metastases and/or a sarcomatous development were observed (Mentzel).
ManifestationThis section has been translated automatically.
Mostly adults in the 3rd-6th decade of life. Less often also children
LocalizationThis section has been translated automatically.
Extremities, preferably lower legs, less frequently on the trunk. A rare "variant" in the facial area (dermatofibroma of the facial region) has been described.
Clinical featuresThis section has been translated automatically.
Solitary or multiple, occasionally itchy or painful, rough, not or only slightly protruding from the surrounding skin level, sometimes also centrally sunken, sharply defined papules (or nodes). The colour is reddish or yellow-brown, also dark brown. The surface is smooth, more often however wart-like rough. Remarkable is the "surprisingly" hard consistency of the new formation (fibroma durum). Dermatofibromas can be enclosed between thumb and index finger like a hard pastille. With lateral pressure the lesion sinks into the depth (= Fitzpatrick sign or dimple sign) while melanocytic naevi protrude.
Some dermatofibromas tend to exophytic growth without a special histological architecture.
The so-called deep infiltrating dermatofibroma is mainly found on the trunk and extremities of younger people. At 1-2 cm in diameter, they are larger than the usual forms and must be separated from Dermatofibrosarcoma protuberans.
Dermatofibromas the size of a palm of the hand (giant dermatofibroma) are rare.
Rare are eruptive multiple dermatofibromas in the immunosuppressed organism.
HistologyThis section has been translated automatically.
- Circumscribed dermal tumour with diffuse accumulations of spindly cells embedded in eosinophilic connective tissue, usually not sharply defined to the side and depth. Occasionally with lipid or haemosiderin storage. Giant cells of the foreign body or touton type, vascularization with endothelial swelling. The overlying epidermis is acanthotic; possibly basal cell carcinoma-like proliferation. Dermatofibromas may show a mat-like, intensively interlaced (storiform) pattern. Older dermatofibromas can change into a cell-poor fibrous stage.
- Immunohistochemically, all cells involved express the non-specific marker vimentin; phagocytizing dermal dendritic cells (dendrophages) are FXIIIa positive.
- Histological variants of dermatofibroma:
- Dermatofibroma with granular cells: Occurrence of large bright, S100 negative and PAS positive cells with granulated cytoplasm, comparable to granular cell tumor).
- Epithelioid cell histiocytoma: tumor of large epithelioid cells with large eosinophilic cytoplasm and mostly vesicular nuclei. Occasionally also multinucleated giant cells.
- Neurothekeoma, cellular
- Dermatofibroma with monster cells
- Ossifying dermatofibroma: with ossification zones
- Xanthomatized dermatofibroma: with fat deposits
- Dermatofibroma, hemosiderin storing
- Myxoid dermatofibroma: with myxoid degeneration zones
- Desmoplastic dermatofibroma: Significantly increased collagen production compared to classical dermatofibroma. The same applies to sclerotic and fibrosing dermatofibroma.
- Deep penetrating dermatofibroma: Dermatofibroma with infiltration of the subcutaneous adipose tissue. DD: Dermatofibrosarcoma protuberans.
- Dermatofibroma in the facial area (rare tumours, often rich in cells, which infiltrate deeper structures at an early stage)
- Aneurysmatic dermatofibroma (characterized by rapid growth, the parenchyma is characterized by bleeding and large pseudovascular cavities; high (20%) local recurrence rate after excision)
- Giant cell langiohistiocytoma with shot-shot-like distribution of papules in a circumscribed region (mostly thigh).
- Cell-rich dermatofibroma (more frequent in young men in the lower extremities; increased proliferative activity; tumours contain actin-positive myofibroblasts. Local recurrence rate is increased (25%). Rare metastases. Differentiation from Dermatofibrosarcoma protuberans necessary)
- Atypical (pseuodsarcomatous) dermatofibroma (more common on the extremities, also on the head and neck. Significant cell and nuclear polymorphism, giant multinucleated cells, atypical mitoses; increased rate of local recurrence, very rarely metastasis) - see also under Fasciitis nodularis pseudosarcomatosa
- Metastatic dermatofibroma (the very rare metastasis concerns the cell-rich, the atypical pseudosarcomatous and the aneurysmatic dermatofibroma).
Differential diagnosisThis section has been translated automatically.
TherapyThis section has been translated automatically.
Note(s)This section has been translated automatically.
LiteratureThis section has been translated automatically.
- Alves FA et al (2003) Benign fibrous histiocytoma of the buccal mucosa: case report with immunohistochemical features. J Oral Maxillofac Surgery 61: 269-271
- Hui P et al (2002) Clonal analysis of cutaneous fibrous histiocytoma (dermatofibroma). J Cutan Pathol 29: 385-389
- Hill H (2006) Fibrohistiocytic skin tumors. J Dtsch Dermatol Ges 4: 544-555
- Mentzel T (2016) Mesenchymal tumors of the skin. In: Cerroni L et al. histopathology of the skin. Springer-Verlag Berlin Heidelberg New-York S 742-744
- Sellheyer K, Smoller BR (2003) Dermatofibroma: upregulation of syndecan-1 expression in mesenchymal tissue. At J Dermatopathol 25: 392-398
- Yamamoto T et al (2003) Role of mast cells in dermatofibroma: recent viewpoints into the pathogenesis. Eur J Dermatol 13: 419-423
- Zaccaria E et al (2008) Multiple eruptive dermatofibromas and immunosuppression: report of two cases and review of the literature. Int J Dermatol 47: 723-727
Incoming links (38)Angiohistiocytoma with giant cells; Angioleiomyoma; Bacillary angiomatosis; Blue nevus; Chondrome; Collagenom storiformes; Dermatofibroma hemosiderin storing; Dermatofibroma with monster cells; Dermatofibroma xanthomatized; Factor xiiia; ... Show all
Outgoing links (21)Acanthosis; Angiohistiocytoma with giant cells; Connective tissue nevus; Cutaneous mastocytoma; Dermatofibroma hemosiderin storing; Dermatofibroma with monster cells; Dermatofibroma xanthomatized; Dermatofibrosarcoma protuberans (overview); Excision; Fasciitis nodularis pseudosarcomatosa; ... Show all
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