Epithelioid cell histiocytoma with underlying artery damage

Although epithelioid cell histiocytoma is considered a variant of fibrous histiocytoma (dermatofibroma), the histogenesis of this condition remains controversial. A recent investigation suggested the possibility that epithelioid cell histiocytoma is an angioformative fibrous histiocytoma. We report a case of epithelioid cell histiocytoma underlying a damaged artery. This epithelioid cell histiocytoma with a central area of hemorrhage was associated with a medium-sized artery in the reticular dermis running vertically up to the lesion. Both the artery in the reticular dermis and its centrally branched artery in the subcutaneous tissue showed mural injury and intraluminal epithelioid endothelial proliferation. Immunohistochemically, the labeling rate for each of the antibodies studied in the epithlioid cells was as follows: 40% for Factor XIIIa, 5% for CD34, 20% for factor VIII-related antigen, and 10% for alpha-smooth muscle cell actin. This case may support the view that epithelioid cell histiocytoma is a vascular and angioformative fibrous histiocytoma.     

Metastatic aneurysmal fibrous histiocytoma in a 20-year-old woman: A rare case report with review of the literature and discussion of its genomic features

Aneurysmal fibrous histiocytoma is an uncommon variant of cutaneous fibrous histiocytomas with a local recurrence rate of 19%. We present a case of aneurysmal fibrous histiocytoma in a 20-year-old female with a regional lymph node metastasis and subsequent satellite nodule. The patient initially presented with a 1-month history of two palpable nodules in left lower anterior shoulder and left axilla. Needle core biopsies from both lesions revealed an atypical spindle cell neoplasm with a differential diagnosis of aneurysmal fibrous histiocytoma and angiomatoid fibrous histiocytoma. The axillary dissection confirmed a metastatic deposit in 1 out of 22 lymph nodes. At 6 months a satellite nodule arose between the resection scar and the axilla histopathologically demonstrating a cellular spindle cell nodule at the dermis subcutaneous junction with large, blood-filled pseudovascular spaces lined by histiocytes. The periphery of the lesion showed collagen trapping without a lymphoplasmacytic infiltrate. The lesional cells were diffusely positive for CD10 and focally for CD68 and Illumina RNA fusion panel sequencing was negative. Herein we present this case of metastatic aneurysmal fibrous histiocytoma with review of the literature and discussion of biology, cytogenetic alterations, and differential diagnosis.     

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.     

Fibrohistiocytic skin tumors

The fibrohistiocytic tumors of the skin are a heterogeneous group of dermal/subcutaneous mesenchymal neoplasms which show fibroblastic, myofibroblastic and histiocytic (macrophage‐like) differentiation, often one beside the other in the same tumor. “Fibrohistiocytic” means in this context the morphologic similarity of the cells with fibroblasts and histiocytes. The WHO classification of 2005 includes the following entities as fibrohistiocytic tumors of the skin: Benign: 1. Fibrous histiocytoma (FH)/(synonymous: Dermatofibroma. Variants of FH: 1a. cellular fibrous histiocytoma, 1b. atypical (pseudosarcomatous) fibrous histiocytoma, 1c. aneurysmatic fibrous histiocytoma, 1d. epithelioid fibrous histiocytoma; 2. dermatomyofibroma; 3. (juvenile) xanthogranuloma. Intermediate: 4. plexiform fibrohistiocytic tumor; 5. dermatofibrosarcoma protuberans; 6. atypical Fibroxanthoma. Malignant: 7. malignant fibrous histiocytoma. All these entities are reviewed in this paper with particular attention devoted to differential diagnostic considerations.     

Aneurysmal fibrous histiocytoma: an unusual variant of cutaneous fibrous histiocytoma

Aneurysmal fibrous histiocytoma (AFH) (Santa-Cruz DJ, Kyriakos M. Aneurysmal ('Angiomatoid') fibrous histiocytoma of the skin. Cancer 1981;47:2053-2061) is a distinct but poorly recognized clinicopathological variant of cutaneous fibrous histiocytoma (CFH) that may result from the slow extravasation of blood into the tumour. The resulting lesion can have a very different clinicopathological appearance resulting in diagnostic confusion. We describe a patient with an AFH that presented as a pigmented nodule on the foot and discuss clinical recognition and histological differentiation from other tumours.     

Aneurysmal fibrous histiocytoma showing transition from factor XIIIa-positive to -negative

A 39-year-old woman visited us because of a subcutaneous induration on her forehead of 7 months' duration. The tumor was tender, firm, and colored blue-black. Microscopically, the tumor was composed of fibroblastic and histiocytic cells showing no atypicality. In some part intra- or extracellular haemosiderin was diffusely seen. There were some blood-filled spaces of varying size without endothelial lining. From these findings, this case was diagnosed as aneurysmal fibrous histiocytoma (AFH), a variant form of dermatofibroma. Immunohistochemical analysis showed that factor XIIIa-positive histiocytic cells were distributed in the area without haemosiderin, but such cells were absent in the area with its deposition. Furthermore, the cells near the blood-filled space showed transition from factor XIIIa-positive to -negative, suggesting that the stromal instability induced by the attenuation of factor XIII may lead the formation of the blood-filled spaces in AFH.     

Case for diagnosis

We report the case of an 11-year-old male patient with a histopathological and immunohistochemical diagnosis of dermatofibroma with an atypical clinical presentation on the right forearm. Although dermatofibroma is considered a benign skin tumor, some of its differential diagnoses, such as dermatofibrosarcoma protuberans and malignant fibrous histiocytoma, are truly aggressive. Lesions with atypical clinical aspects and topology associated with specific histopathological variants are some of the criteria for complete tumor excision.     

Multiple clustered dermatofibroma presenting in a segmental distribution

Multiple dermatofibromas is a rare entity consisting of more than fifteen lesions. Multiple clustered dermatofibroma is a distinct variant of multiple dermatofibromas and is defined as a well‐demarcated plaque composed of individual dermatofibromas. We report a 16‐year‐old boy with multiple clustered dermatofibroma in a segmental distribution, which has previously not been reported in the literature.     

Recurrent malignant fibrous histiocytoma with expression of cytokeratin.

A case of locally recurrent malignant fibrous histiocytoma was documented in a 70-year-old man. He first noticed a subcutaneous nodule forty years previously. The tumor was surgically removed four times during the last four years with local recurrence on every occasion. In the recurrent tumors, the tumor cells almost completely replaced the whole dermis and invaded skeletal muscles. They were composed of pleomorphic spindle cells arranged in a storiform pattern and bizarre histiocytic cells, which were present principally in the deeper portions of the tumor. Both types of tumor cells showed marked nuclear atypicality. In the primary tumor, surrounding a large necrotic area, spindle-shaped cells were arranged in a storiform pattern. These tumor cells exhibited only mild nuclear atypia. The recurrent tumor was strongly positive for vimentin and alpha-1-antichymotrypsin. Most tumor cells were also weakly positive for KL1, a monoclonal antibody for keratin. A Western-blot analysis revealed the presence of two bands (62 and 69 Kd) reacting with KL1 in the fractions which were obtained from the tumor according to the method for keratin extraction.     

A case of polypoid dermatofibroma

Dermatofibroma is a common benign cutaneous tumor that usually appears as a slowly growing firm nodule. Polypoid nodular dermatofibroma is a variant type that is rarely encountered. We reported a case of polypoid dermatofibroma with a review of the previously reported cases. Polypoid dermatofibroma tends to arise on the leg, especially below the knee. Its size is often larger than that of common dermatofibroma. It is speculated that both the underlying firm tissue and long-term development may lead the tumor to form a polypoid appearance.     

Epidermal Inclusion Cyst Embedded in a Recurrent Benign Fibrous Histiocytoma

Epidermal infundibular cysts have been known to arise from implantation of epidermis in the dermis or subcutaneous tissues. The present case illustrates the theory of implantation in an epidermal inclusion cyst in a previously operated case of recurrent benign fibrous histiocytoma.     

Atrophic dermatofibroma

Dermatofibroma is a benign fibrohistiocytic tumor, common and easily diagnosed when classical clinicopathologic features are present. The atrophic variant of dermatofibroma is of uncertain origin. This lesion is characterized clinically by a flat or atrophic and depressible surface. Histopathological features show reduction of the thickness of the dermis and elastic fibers. We report a typical case of this uncommon and probably underdiagnosed variant.     

Flow-cytometric DNA analysis in cutaneous fibrohistiocytic tumors

BACKGROUND: Fibrohistiocytic tumors are rare skin tumors. There are many kinds of fibrohistiocytic tumors. It is often difficult to differentiate dermatofibrosarcoma protuberans (DFSP) and malignant fibrous histiocytoma (MFH) from dermatofibroma (DF) and other benign tumors. OBJECTIVE: In this study, the possible usefulness of DNA ploidy for the differentiation was studied. METHODS: Five MFH, 9 DFSP, 3 DF, 2 lipofibromas and 2 scars were studied for DNA ploidy using a flow cytometer. RESULTS: All the 7 benign tumors showed a diploid pattern. Of 14 malignant fibrohistiocytic tumors, 8 cases (57.1%) showed an aneuploid and 6 a diploid pattern. Two of 5 MFH (40.0%) and 6 of 9 DFSP (66.7%) showed an aneuploid pattern. These results showed that fibrohistiocytic tumors with an aneuploid pattern are malignant, though those with a diploid pattern may be benign or malignant. CONCLUSION: Analysis of DNA ploidy using flow cytometry was concluded to be useful for the differentiation of malignant fibrohistiocytic tumors from benign ones.     

Benign fibrous histiocytoma of the eyelid with an unusual clinical presentation

Benign fibrous histiocytoma is a common soft tissue tumor that can be deep or superficially located. Although the deep type of fibrous histiocytoma has a predilection for the orbit, the eyelids are an unusual location for the cutaneous type. A 42-year-old woman had bilateral yellowish nodular masses of the eyelids for two years. Pathological examination after excision revealed benign fibrous histiocytoma. Our case is an unusual clinical presentation of cutaneous fibrous histiocytoma as well as a rare location such as the eyelids.     

动脉瘤样纤维组织细胞瘤一例

患者,女,71岁。左胫前黑褐色结节5年。结合临床症状和组织病理检查,诊断为动脉瘤样纤维组织细胞瘤。给予手术完整切除治疗,随访至今未复发。     

Benign cellular fibrous histiocytoma with erosion of the phalanx

Fibrohistiocytic tumors are characterized by the presence of fibroblast like spindle cells and histiocytes. The benign fibrous histiocytoma (dermatofibroma, BFH) as well as the malignant dermatofibrosarcoma protuberans (DFSP) and the malignant fibrous histiocytoma (MFH) belong to this group. A recurrent painful, hard 2 cm tumor on the left hallux of a 54-year-old woman led to an erosion of the underlying phalanx. The patient had suffered from ingrown toenails for more than 10 years. Histologically there was a deep penetrating fibrohistiocytic tumor that grew in a storiform pattern with interspersed foam cells. The tumor was CD34 negative and mitoses were scarce. The diagnosis was benign cellular fibrous histiocytoma (BZFH). BZFH belong to the group of BFH with a high recurrence rate especially after incomplete removal. Damage to the underlying bone has not been reported so far.     

Aneurysmal Benign Fibrous Histiocytoma with Atrophic Features

Aneurysmal benign fibrous histiocytoma is an uncommon pathologic variant of dermatofibroma. In addition to the features of a typical dermatofibroma, it has large cleft-like or cavernous blood-filled spaces with numerous hemosiderin pigments. It should be differentiated from angiomatoid malignant fibrous histiocytoma, malignant melanoma, and vascular tumors such as Kaposi''s sarcoma and angiosarcoma. Atrophic dermatofibroma is also a rare variant of dermatofibroma, and the combination of aneurysmal and atrophic features is rarer still. We report a case of aneurysmal benign fibrous histiocytoma with atrophic features in a 27-year-old male who had a grayish-brown atrophic patchy lesion on his back for 2 years.     

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.     

Melanoma associated with a dermatofibroma

BACKGROUND: Dermatofibromas are common benign cutaneous fibrohistiocytic neoplasms, whereas melanomas are potentially aggressive malignancies. Differentiating these two entities can occasionally be difficult. METHODS: We report the case of a 56-year-old female presenting with a firm pink papule on the left thigh. RESULTS: Histopathology revealed atypical melanocytes in the epidermis and papillary dermis with numerous mitotic figures and intraepidermal pagetoid spread. Within the dermis was a poorly demarcated collection of epithelioid and spindled cells with intermixed keloidal collagen. The atypical melanocytes stained for MART-1 and S-100, whereas the underlying fibrohistiocytic tumor took up factor XIIIa immunostain, confirming the diagnosis of invasive malignant melanoma occurring in association with a dermatofibroma. CONCLUSIONS: This case emphasizes the role of immunohistochemical stains in correctly diagnosing melanocytic and histiocytic neoplasms.