Multiple clustered dermatofibroma with overlying sebaceous hyperplasia

Multiple clustered dermatofibroma is a very rare clinical variant of the dermatofibroma, and sebaceous differentiation overlying dermatofibromas is also unusual. We report the first case of a multiple clustered dermatofibroma with overlying sebaceous hyperplasia.     

Multiple clustered dermatofibroma: case report and review of the literature

The presence of multiple dermatofibromas is rare and is defined as more than 15 lesions. Multiple clustered dermatofibroma (MCDF) is a distinct entity with only 12 reported cases in the literature. MCDF occurs in healthy individuals of both sexes in the first to third decades on the lower half of the body and portends an excellent prognosis. On histology, MCDF is consistent with benign dermatofibromas. We report a 31‐year‐old healthy Hispanic woman with a 14‐year history of slowly progressive MCDF located on her right hip initially misdiagnosed as dermatofibrosarcoma protuberans. We believe this case represents the 13th report of MCDF in the literature and the second from North America. Gershtenson PC, Krunic AL, Chen HM. Multiple clustered dermatofibroma: case report and review of the literature.     

Multiple eruptive myxoid dermatofibromas: report of first case and review of literature

Multiple eruptive dermatofibromas are a rare presentation of dermatofibroma which are frequently associated with underlying diseases such as human immunodeficiency virus infection or lupus erythematosus. Eruptive dermatofibromas generally present a characteristic histology with a poorly circumscribed lesion showing hyperplasia of the epidermis, prominent bundles of collagen and a diffuse proliferation of fibrocytes. We report an unusual case of multiple eruptive dermatofibromas showing massive depositions of mucin within the dermis. A 20-year-old woman presented with nearly 100 red to yellowish papules and nodules distributed symmetrically all over the integument which developed over a period of 9 years. Comprehensive clinical and laboratory diagnostics showed no signs indicating any underlying disease. To our knowledge this is the first report of multiple eruptive myxoid dermatofibromas. We consider this case to be a unique presentation of multiple eruptive dermatofibroma showing massive deposition of mucin.     

Multiple cutaneous fibrous histiocytomas in association with systemic lupus erythematosus

Cutaneous fibrous histiocytomas are usually regarded as superficial lesions and commonly known as dermatofibromas; however, unusual cases histologically showing fibrohistiocytic proliferation extending into the deeper dermis or subcutaneous tissues are occasionally experienced. Some authors propose this type as benign fibrous histiocytoma of the skin, distinct from dermatofibroma. We describe herein a case of systemic lupus erythematosus (SLE) who developed multiple nodules on the face, trunk and extremities. The nodule on the forehead did not present a typical clinical appearance of dermatofibroma, and histopathological examination showed fibrohistiocytic proliferation with a storiform pattern extending into the deep dermis and subcutaneous tissues. By contrast, histology of the nodule on the abdomen showed fibrohistiocytic proliferation confined to the dermis and compatible with dermatofibroma. Although multiple dermatofibromas are occasionally seen in patients with SLE, benign fibrous histiocytoma of the skin showing deeper invasion than dermatofibroma is rarely associated with SLE.     

Multiple dermatofibromas and systemic lupus erythematosus

We report on three black women with multiple dermatofibromas and systemic lupus erythematosus. In one patient occurrence of new dermatofibromas was definitely related to increases in corticosteroid dosage, but in another the dermatofibromas predated all treatment. Histopathologic, ultrastructural, and direct immunofluorescence studies of lesions of two of the patients showed characteristic changes of dermatofibroma but did not reveal a specific cause. This finding in patients with systemic lupus erythematosus is probably much more common than has previously been appreciated.     

Dermatofibroma: a possible model of local fibrosis with epithelial/mesenchymal cell interaction

Dermatofibromas are benign dermal nodules usually seen on the extremities; however, whether a dermatofibroma is a reactive fibrous hyperplasia or a true neoplasm is still unclear. Fibrous type dermatofibromas might be regarded as the symptom of local fibrotic processes and thus present a possible model of local fibrosis. Interaction between proliferated dermatofibroma fibroblasts and overlying elongated epidermis suggests a relationship between keratinocytes and mesenchymal cells. We herein describe current insights into the pathogenesis of dermatofibromas and explore the possible involvement of immunocytes around fibroblasts and effector cells which play an important role in the development of dermatofibromas.

Conflicts of interest

None declared     

Sebaceous hyperplasia overlying a dermatofibroma

Epithelial changes overlying dermatofibromas are well recognized. The presence of sebaceous differentiation overlying a dermatofibroma is unusual. We report two patients with sebaceous hyperplasia overlying a dermatofibroma and discuss possible mechanisms for induction of the epithelium and adnexa by the mesenchyme in a dermatofibroma.     

皮肤纤维瘤中Smad2,Smad3和Smad4 mRNA的表达

目的探讨转化生长因子β(TGF-β)/Smad信号转导途径中Smad2,Smad3和Smad4 mRNA在皮肤纤维瘤中的表达水平及其意义。方法应用反转录-实时定量聚合酶链式反应(RTand quantitative Real-Time PCR)技术分别检测皮肤纤维瘤与正常对照皮肤中Smad2,Smad3和Smad4的mRNA表达。结果皮肤纤维瘤真皮瘤体中Smad2,Smad3和Smad4的mRNA表达水平均显著高于正常人对照皮肤(分别是正常对照的3.56倍,3.82和3.63倍)。结论皮肤纤维瘤中Smad2,Smad3和Smad4表达上调提示了TGF-β信号转导通路的活化,这可能有助于皮肤纤维瘤中纤维增殖状态的形成和维持。     

A Clinical and Histopathological Study of 122 Cases of Dermatofibroma (Benign Fibrous Histiocytoma)

Background

Many variants of dermatofibromas have been described, and being aware of the variants of dermatofibromas is important to avoid misdiagnosis.

Objective

We wanted to evaluate the clinical and pathologic characteristics of 122 cases of dermatofibromas.

Methods

We retrospectively reviewed the medical records and 122 biopsy specimens of 92 patients who were diagnosed with dermatofibroma in the Department of Dermatology at Eulji Hospital of Eulji University between January 2000 and March 2010.

Results

Nearly 80% of the cases occurred between the ages of 20 and 49 years, with an overall predominance of females. Over 70% of the lesions were found on the extremities. The most common histologic variant was a fibrocollagenous dermatofibroma (40.1%). Other variants included histiocytic (13.1%), cellular (11.5%), aneurysmal (7.4%), angiomatous (6.5%), sclerotic (6.5%), monster (4.9%), palisading (1.6%) and keloidal dermatofibromas (0.8%). There were 9 dermatofibromas (7.3%) that were the mixed type with two co-dominant histologic features.

Conclusion

The results of this study are consistent with previous reports on the clinical features of dermatofibromas. However, we observed several characteristic subtypes of dermatofibroma and we compared the frequency of the histologic subtypes.     

Lichenoid, erosive and ulcerated dermatofibromas. Three additional clinico-pathologic variants

On the occasion of a case of dermatofibroma with histological lichenoid features, we reviewed from our files all the cases in which the epidermis, usually hyperplastic in dermatofibroma, was, in some way, partially or completely destroyed. Among a total of 484 dermatofibromas, we found three lichenoid, six erosive and two ulcerated cases. In the three lichenoid cases, the columnar epidermal basal cells were lacking (squamotization of the basal layer) and in two of them there was a cleft between the epidermis and the dermatofibroma. Three of the six eroded cases were large pedunculated dermatofibromas with inflammatory phenomena of variable intensity. One case was in the center of a plaque of lichen simplex chronicus with some eroded area. In the other two cases, as well as in the two ulcerated lesions, neither inflammation nor epidermal changes usually attributed to rubbing or scratching were seen. Only in three of the eleven cases dermatofibroma was proposed (with question mark) as a clinical diagnosis. Both follow-up and histopathology supported the benign nature of these cases. We may conclude that: i) Lichenoid, erosive and ulcerated changes in dermatofibroma are infrequent phenomena which may make a clinical diagnosis difficult; and ii) in the presence of an otherwise histopathologically typical dermatofibroma, erosion and ulceration should not be considered as suspicious of malignancy.     

Lentiginous Melanocytic Hyperplasia Overlying Dermatofibroma

There are occasional reports of proliferative epidermal changes overlying dermatofibromas. We report the first case to our knowledge of a dermatofibroma with overlying lentiginous melanocytic hyperplasia.     

Central white scarlike patch: a dermatoscopic clue for the diagnosis of dermatofibroma

In this study, dermatoscopic examination of 24 dermatofibromas was performed to evaluate specific dermoscopic criteria. A central white scarlike patch was appreciable in 22 of 24 lesions, whereas 20 of 24 dermatofibromas exhibited a delicate pigment network at the periphery. This stereotypical dermatoscopic finding allowed the diagnosis of dermatofibroma in most instances. (J Am Acad Dermatol 2000;43:1123-5.).     

Multiple cellular neurothekeomas in a middle‐aged woman including the lower extremity: A case report and review of the current literature

Cellular neurothekeoma is a benign cutaneous neoplasm that typically occurs on the head, neck, and upper body of young adults with a slight female predominance. It is a rare lesion to diagnose and multiple neurothekeomas in one patient are even more uncommon finding. We present a case of multiple neurothekeomas in a middle‐aged woman with lower extremity involvement and summarize the current literature on multiple neurothekeoma patients. A 46‐year‐old female presented with nearly one dozen skin‐colored papules on the head, upper limb, and lower limb. The lesions were clinically diagnosed as dermatofibromas and a nevus. Eight lesions were biopsied and confirmed to be cellular neurothekeomas, with one initially misinterpreted on histology as a dermatofibroma. Awareness of cellular neurothekeoma as a diagnostic entity and the possibility of atypical presentations as seen in our case (eg, in multiple numbers, in older adults, and on the lower extremity) are important in allowing for accurate clinical and histological diagnosis of these lesions. The possibility of a syndromic association with multiple cellular neurothekeomas should be explored further.     

Palmar dermatofibroma in a patient with multiple porokeratosis

Although dermatofibromas are not uncommon benign dermal nodules, palms are rarely involved. Herein, a rare case of palmar dermatofibroma was described, which occurred in a patient with porokeratosis.     

A case of perforating dermatofibroma with floret‐like giant cells

Dermatofibromas are slow‐growing solitary nodules, composed mostly of a dermal proliferation of spindle cells and epithelioid cells. Some dermatofibromas present with multinucleated giant cells, such as Touton, foreign body, and osteoclast‐like cells. We report a case of dermatofibroma containing both Touton giant cells and floret‐type cells. A 12‐year‐old boy presented with a 6‐mm, firm, nontender, dusky‐red to greyish dermal nodule on his left popliteal fossa. As suggested clinically by the central opening, perforation of the epidermis with partial extrusion of the dermal components, including macrophages and vertically oriented collagen bundles, via transepidermal elimination, were detected. In the upper dermis, collagen trapping and mostly epithelioid cells with many giant cells were seen, while the lower part contained mainly spindle cells in a storiform pattern. Multinucleated giant cells scattered in the upper dermis were mainly floret‐type multinucleated giant cells with star‐shaped cytoplasmic projections, associated with some Touton giant cells. To our knowledge, this is the first report of a perforating dermatofibroma with floret‐type multinucleated giant cells.     

Squamous cell carcinoma in situ overlying dermatofibroma

There are occasional reports of benign proliferative epidermal changes overlying dermatofibromas and rare cases of invasive basal cell carcinoma. We report the first case to our knowledge of a dermatofibroma with overlying in situ squamous cell carcinoma.     

Congenital Multiple Clustered Dermatofibroma in a 12‐Year‐Old Girl

Abstract: Congenital multiple clustered dermatofibroma (MCDF) is a rare, idiopathic, benign tumor presenting at birth as an asymptomatic hyperpigmented patch that is stable until puberty, at which time it enlarges and develops papules. Ultimately, MCDF appears to follow a stable, benign course. We present a case of a 12‐year‐old girl with congenital MCDF. To our knowledge, this is only the third reported case of congenital presentation of MCDF and the only case featuring atrophoderma‐like depression.     

Giant dermatofibroma with monster cells.

We report a case of a 64-year-old woman with a giant dermatofibroma on her back with the unusual histologic feature of monster cells. The firm, exophytic, 3-cm nodule had purple and yellow components with surface telangiectasia. Histologic examination demonstrated characteristic findings of a dermatofibroma, including rete ridge flattening and bridging; a stroma containing scattered, large, round, eosinophilic collagen bundles; and a polymorphous dermal infiltrate of spindle and xanthomatous cells with scattered siderophages. Some xanthomatous cells demonstrated features consistent with monster cells, including huge bizarre nuclei and one or more nucleoli. Immunohistochemical staining for factor XIIIa was positive. A diagnosis of giant dermatofibroma with monster cells (DFMC) was made. Giant dermatofibromas are rare, with monster cells being an uncommon finding in dermatofibroma. To our knowledge, this is the first report of DFMC.     

Non-polarizable collagen in dermatofibrosarcoma protuberans: a useful diagnostic aid

The stroma in dermatofibrosarcoma protuberans (DFSP) stains with trichrome, but is not polarizable (birefringent, doubly refractile). The usefulness of polarizing neoplastic stroma as a diagnostic aid in distinguishing DFSP from dermatofibroma and fibromatosis was evaluated. Forty cases of dermatofibroma of all types, 12 cases of dermal fibromatosis, and 15 cases of DFSP were examined. None of DFSPs contained polarizable collagen, whereas 11 of the 12 (92%) fibromatoses and 35 of the 40 (88%) dermatofibromas did. Of the 5 dermatofibromas that did not polarize, all were composed primarily of round to polyhedral histiocytic cells, including foam cells, frequently surrounding small obliterated capillaries. Although not pathognomonic, the presence of nonpolarizable collagen appears to be an additional histological marker useful in differentiating DFSP from dermatofibroma and fibromatosis.     

Pediatric dermatofibromas: Truncal predominance in younger children

Pediatric dermatofibromas are considered rare in young children and have not been well characterized, often misdiagnosed clinically. We performed a retrospective case series of children younger than 18 years with histopathologically diagnosed dermatofibromas at our institutions and evaluated age at onset and diagnosis, sex, lesion location, and size, associated symptoms, change over time, and pre-biopsy diagnosis. Overall, dermatofibromas were most common on the back and chest (20/53; 38%), followed by the legs (15/53; 28%) and arms (12/53; 23%) with the most common pre-biopsy diagnosis of “cyst” (23/53; 43%), followed by dermatofibroma (16/53; 30%), and pilomatricoma (12/53; 23%). Our study reinforces previous findings of truncal predominance of pediatric dermatofibromas, different from adults.