Digital dermatofibromas--common lesion, uncommon location: a series of 26 cases and review of the literature

Dermatofibroma (DF), also referred to as cutaneous fibrous histiocytoma (CFH), is a common tumor of the skin presenting as a firm nodule located predominantly on the limbs and shoulder and pelvic girdles that often extends into superficial subcutaneous tissue. This is a retrospective study of 26 DFs located on digits. All case slides were retrieved from saved files for diagnostic verification. One case was rejected after revision of the diagnosis to giant cell tumor of the tendon sheath. The 26 remaining cases constitute this reported series. Digital DFs affected 27 to 70 year-olds in a 2.25:1 male to female ratio. The most common clinical diagnosis submitted was "growth" or wart. In only 6 out of the 26 cases was the pre-biopsy diagnosis of DF ventured. Although lesional tissue went to dermal margins in 14 specimens, only one has been re-excised in follow up ranging from 2 months to 10 years. Because DFs can resemble several entities including leiomyosarcoma and dermatofibrosarcoma protuberans, a lack of familiarity with the occurrence of DF on the digits may result in more aggressive treatment than otherwise necessary. DF should be in the differential diagnosis of circumscribed, firm nodules presenting on the digits.     

Cutaneous balloon cell dermatofibroma (fibrous histiocytoma)

Dermatofibroma (DF) or cutaneous fibrous histiocytoma is a common benign skin tumor that exhibits multiple, distinct histologic variants. Although clear cell DF has been described in the literature, balloon cell degeneration causing a clear cell DF phenotype has been not been reported to date. Herein, we describe the clinicopathologic findings of balloon cell DF arising on the heel of a 43-year-old man. Clinically, it presented as enlarging tan-white, ulcerated, firm 1.5 cm nodule, clinically suspected to be pyogenic granuloma. Excisional biopsy revealed a circumscribed fibrous tumor populated by mostly clear and spindle cells. A zonal arrangement separated the varied tumor cells where the most superficial, polypoid area showed large, clear polygonal balloon cells; the mid-dermal zone demonstrated a transition between balloon cells, epithelioid cells, and spindle cells; and the deep dermal zone had storiform arrangement of spindle cells, with the fascicles separated by coarse collagen bundles. A CD10+ > CD68+ > Factor XIIIa+ immunophenotype was identified with negative immunolabeling for S-100 protein, HMB-45, cytokeratin AE1/AE3, desmin, smooth muscle actin, lysozyme, and leukocyte common antigen (LCA). Ultrastructurally, the clear tumor cells were filled with multiple, empty, nonmembrane bound vacuoles of varying size. No recurrence has been described after complete excision and 7 months of follow up. DF with balloon cell change, likely secondary to persistent irritation, should be added to the differential diagnosis of cutaneous primary and metastatic neoplasms showing balloon cell degeneration such as balloon cell melanocytic nevi and renal cell carcinoma, respectively.     

Giant cell tumor of skin

Giant cell tumor of the skin is a rare entity showing gross and histological features similar to those of giant cell tumor of the bone. We report a case of malignant giant cell tumor of the thigh in a 55-year-old man. Histological features showed a biphasic population of mononuclear cells admixed with osteoclast-like giant cells. The nuclei of the giant cells were similar to those of the mononuclear cells. This tumor should be distinguished from a variety of cutaneous neoplasms that contain multinucleated giant cells.     

Cutaneous metastases of a giant cell tumor of bone: case report

A 47-year-old patient with the previous history of a giant cell tumor of the left femur presented with 3 cutaneous nodules located on the face. Histologic examination revealed skin metastases of a giant cell tumor of bone, with dermal and subcutaneous nodules characterized by multinucleate giant cells and mononuclear cells. The patient died 10 months later from widespread metastases to the lung and brain. A panel of enzymo- and immunohistochemical markers reactive and osteoclastic, fibroblastic and histiocytic determinants was tested on the cutaneous lesions. The results indicated osteoclastic lineage of the multinucleate giant cells whereas the mononuclear cells showed features of fibroblastic differentiation. Cutaneous metastasis from a giant cell tumor of bone is an extraordinary event and so far has only been reported once.     

Giant dermatofibroma with granular cell changes: side‐effect of bee‐venom acupuncture?

Dermatofibroma (DF) is a common benign fibrohistiocytic tumour with a predilection for the legs in middle-aged women. Giant DF, a rare clinical variant of DF, is characterized by its unusually large size. Granular cell change is typical of granular cell tumour, but can be observed in diverse cell lineages. Traumatic factors may be involved in the pathogenesis of giant DF and cellular granularity. We describe a 49-year-old Korean man with a giant DF showing granular cell differentiation, which may have been caused in part by multiple treatments with bee-venom acupuncture.     

Ulcerated dermatofibroma with osteoclast-like giant cells

Background: Ulceration and osteoclast-like giant cells are two pathological features uncommonly seen in dermatofibromas. To our knowledge, the presence of these features has not been previously described within the same lesion.
Methods: We report the clinical, histopathological and immunohistochemical findings of a 38-year-old man with an ulcerated dermatofibroma (DF) on the sole containing OLGC.
Comments: DF, or cutaneous fibrous histiocytoma, is a frequent dermatological lesion with many clinicopathological variants. Therefore, a correct diagnosis is not always straightforward, especially when two rare features co-exist in the same lesion. Differential diagnosis was performed with cutaneous and even non-cutaneous lesions. An explanation for the clinicopathological findings is also described.     

Decreased CD44 expression and stromal hyaluronate accumulation in myxoid dermatofibroma

BACKGROUND: Dermatofibroma (DF) is a common benign histiocytic tumor, which has several clinicopathological variants. Myxoid DF is one of these variants, which is characterized by a stromal mucin deposition. CD44 is a polymorphic transmembrane glycoprotein and the principal cell surface receptor of hyaluronate (HA), the major component of the extracellular matrix. In a recent study, we have observed an abnormal accumulation of HA in the superficial dermis of transgenic mice with a keratinocyte-specific CD44 expression defect. We have also shown that HA was accumulated in large amounts in the superficial dermis of lichen sclerosus et atrophicus (LSA) lesions and that the epidermal CD44 expression of LSA skin was significantly decreased or lost. In an another study, we have suggested that a decrease in CD44 expression in follicular epithelial proliferations might be correlated with an abnormal HA accumulation in perifollicular solitary cutaneous myxoma. Recently we have also demonstrated that classical DF lesions displayed a strong CD44 expression in tumor cells and a weak HA positivity in tumor stroma whereas CD44 expression was significantly reduced or absent in dermatofibrosarcoma lesions and the tumor stroma showed strong HA staining. OBJECTIVE AND METHODS: Here we present 3 cases of myxoid DF, in which we explored the nature of the mucinous material in myxoid stroma by colloidal iron and hyaluronic acid binding protein stainings, as well as the expression of CD44 in the tumor cells by immunohistochemistry. RESULTS: We show that HA is accumulated in the stroma of all myxoid DF lesions with a significant decrease in CD44 expression in the tumor cells. CONCLUSION: Our results suggest that a decrease in CD44 expression in the tumor cells may result in stromal myxoid changes characterized by an abnormal HA accumulation in myxoid DF.     

Giant cutaneous angiomyxoma

A case of giant cutaneous angiomyxoma, an unusual cutaneous tumor, is reported. To the best of our knowledge, it is the largest of its kind that has been recorded. The purpose of this report is to acquaint the reader with this rare cutaneous neoplasm and its management.     

Cutaneous sarcomatoid carcinoma with features of giant cell tumor of soft parts--a case report

We report here a previously undescribed tumor in a 72-year-old patient who had a nasal cutaneous sarcomatoid carcinoma. The epithelial component resembles a skin adnexal tumor, and the sarcomatous component resembles a giant cell tumor of soft parts.     

Cutaneous and subcutaneous fibrohistiocytic tumors of intermediate malignancy: an update

The fibrohistiocytic tumors of intermediate malignancy are uncommon mesenchymal tumors, which typically occur in the skin and subcutis and which may pose significant problems for the dermatopathologist. This article reviews the clinical, histopathologic, and genetic features of dermatofibrosarcoma protuberans, giant cell fibroblastoma, angiomatoid (malignant) fibrous histiocytoma, plexiform fibrous histiocytoma, and soft tissue giant cell tumor (of low malignant potential). The differential diagnosis of these tumors with a variety of benign and fully malignant cutaneous soft tissue neoplasms is discussed.     

Differential expression of factor XIIIa and CD34 in cutaneous mesenchymal tumors

The histogenetic relationship amongst various dendritic cells of the dermis which may express markers including factor XIIIa (FXIIIa) or CD34 remains unclear. In this study we utilized a sensitive indirect immunoperoxidase staining technique to identify CD34 and FXIIIa, as well the monocyte/macrophage markers KP-1 and MAC 387 expression in a variety of cutaneous dermal tumors of mesenchymal origin to see if differentia] expression of CD34 vs FXIIIa exists. Tumors studied included dermatofibroma (DF) (N = 10), keloid (N=9), atypical fibroxanthoma (AFX) (N = 3), and dermatofibrosarcoma protuberans (DFSP) (N = 7). DF were all composed of FXIIIa + spindle-shaped and stellate tumor cells (mean score = 4.9 or ≥ 75% FXIIIa +) as previously reported, but these cells rarely (< 10%) expressed CD34. Six of 7 DFSP were found to be > 75% CD34+ and FXIIIa negative, while one DFSP was negative for both CD34 and FXIIIa. In all DFSP, there were trapped FXIIIa+ cells which were distinct from the spindle-shaped tumor cells. AFX showed sparse populations of FXIIIa + cells in the stroma (mean score = 1.33 or 10–25% positive), which were distinct from the atypical giant cells characteristic of these tumors. Keloid similarly contained trapped FXIIIa+ cells (mean score = 0.44 or < 5% positive) that were distinct from the spindle-shaped fibroblasts of the tumor mass. Dendritic and spindle-shaped cells within these tumors were consistently both KP-1 and Mac-387 negative, while all lesions studied were characterized by scattered round, histiocytic cells which were KP-1 + and/or Mac-387 + irrespective of tumor cell type. We suggest that these tumors can be delineated by their relative degrees of FXIIIa and CD34 expression and that these neoplasms may be a useful link with which to study the relationship between CD34+ cells and dermal dendrocytes.     

Hemosiderotic dermatofibroma: report of one case

Dermatofibroma (DF) is a common benign fibrohistiocytic lesion which presents with a wide variety of clinicopathological features. Generally, the clinical diagnosis is easy, but differentiating it from other cutaneous tumors could be difficult in atypical cases and rare variants. We may find at least four different histopathological variants of DF; more than one of which may be present in a single tumor. Hemosiderotic DF is a variant composed of numerous small vessels, extravasated erythrocytes, and intra- and extracellular hemosiderotic deposits. The differential diagnosis may comprise melanoma as well as other melanocytic and nonmelanocytic tumors. We report the case of a 38-year-old man who presented with a hemosiderotic DF on the abdomen.     

Primary giant cell tumor of soft tissue

BACKGROUND: Primary giant cell tumor of soft tissue, also known as soft tissue giant cell tumor of low malignant potential, is a rare soft tissue tumor located in both superficial and deep soft tissue. Histologically, these lesions bear a close resemblance to their bony counterparts, giant cell tumor of bone, with round to spindle-shaped cells intimately admixed with uniformly scattered osteoclast-like multinucleated giant cells. In 1989 in the dermatology literature, two malignant giant cell tumors of soft parts were described that filled the dermis and extended into the subcutaneous tissue. METHODS: The authors report the rare occurrence of a giant cell tumor of soft tissue occurring primarily in the dermis that lacks overtly malignant features and clinically was thought to be an epidermal inclusion cyst. RESULTS: Light microscopy revealed a non-encapsulated cellular dermal tumor containing numerous osteoclast-like giant cells. Cytologic atypia was minimal and the mitotic count averaged 2-3/10 HPF. The histologic differential diagnosis is also discussed. CONCLUSION: Giant cell tumor of soft tissue is a rare neoplasm of the skin, however, recognition of this tumor is important due to its behavior as a low-grade malignancy.     

Primary giant cell tumor of soft tissue in the finger

Primary giant cell tumor of soft tissue (GCTST) arising in a finger is a rare event. We report a case of a 54-year-old man with a primary finger giant cell tumor that appeared histologically identical to giant cell tumor of bone. The patient presented with a cystic mass of the finger. The magnetic resonance imaging showed no relation between the nodule and bone, tendons or synovial tissues. The distinction of this entity from other more common primary finger tumors with giant cell morphology is emphasized.     

Clonal analysis of cutaneous fibrous histiocytoma (dermatofibroma)

BACKGROUND: Dermatofibroma (DF) or cutaneous fibrous histiocytoma is a common benign fibrohistiocytic lesion involving the dermis and subcutis. Histologically, it is subclassified into fibroblastic and histiocytoid forms. Its histogenesis is controversial. While often referred to as a neoplastic process, definite evidence of neoplasia in DF has been lacking. Alternatively, some authorities have suggested that DF is a fibrosing inflammatory process. Diagnostically, the most important question faced is the distinction from dermatofibrosarcoma protuberans (DFSP). Misdiagnosis can occur, as the early phase of DFSP can simulate DF, particularly the deep and cellular forms of DF. METHODS: To address this issue, and to investigate whether DF is in fact a neoplasm, we evaluated 31 examples of DF of various histological types in female patients and assessed clonality by analyzing X-chromosome inactivation as indicated by the methylation status of the androgen receptor gene (HUMARA). Representative cases of DFSP were analyzed for comparison. RESULTS: Among the selected 31 cases of DF, 24 cases provided intact DNA and informative polymorphism at the AR alleles, including one case of recurrent deep fibrous histiocytoma. Among these 24 cases, randomly inactivated AR alleles were observed in 17 cases including a deep, recurrent fibroblastic DF. A non-random inactivation at AR alleles was observed in seven cases, of which six cases showed either typical histiocytoid form of DF (four cases) or mixed cell types with predominant histiocytoid cell type (two cases). One fibroblastic DF also showed a monoclonal pattern. HUMARA analysis of DFSP revealed non-random inactivation of polymorphic AR alleles. CONCLUSIONS: These findings suggest that DF is a heterogeneous process. Monoclonal genotype was found in DFs with histiocytoid or mixed type with predominant histiocytoid features, suggesting that histiocytoid cells probably represent the neoplastic component. The fibroblastic form of DF may represent a reactive fibroblastic proliferation. Alternatively, it may represent a true neoplasm whose neoplastic cell type has been obscured by prominent reactive fibroblastic component.     

An unknown mass: the differential diagnosis of digit tumors

There is little discussion of tumors arising in the digits in the dermatology literature. The patient with an undifferentiated mass of the finger is frequently encountered in the clinic, and variances in presentation of common and uncommon entities pose a challenge that may prompt further investigation for proper diagnosis and treatment. In this review, the authors illustrate the approach and work‐up of an unknown digit mass of a 45‐year‐old female patient. They go on to discuss the presentation and treatment of common tumor lesions of the finger likely to be encountered in the dermatologist's clinic including: ganglion cyst/mucous cyst, giant‐cell tumor, verruca vulgaris, epidermal inclusion cyst, poroma, porocarcinoma, squamous cell carcinoma, basal cell carcinoma, melanoma, infantile digital fibromatosis, acquired digital fibrokeratoma, Koenen's tumor, schwannoma, cutaneous neurofibroma, pyogenic granuloma, hemangioma, glomus tumor, epithelioid sarcoma, and metastatic disease.     

Malignant giant cell tumor of soft parts presenting as a skin tumor

Malignant giant cell tumor of soft parts is a rare neoplasm that histologically resembles a giant cell tumor of bone. It has a distinctive multinodular growth pattern and is composed of numerous osteoclast-like giant cells, histiocytes, and fibroblasts. Although this tumor is usually found in deep soft tissues, a superficial form has been described in the subcutaneous tissue and fascia. The authors report two patients, aged 75 and 78, with malignant giant cell tumors presenting as ulcerating skin nodules of the arm and foot. The tumors were relatively small, measuring less than 3.5 cm in greatest dimension, and involved the entire dermis and subcutaneous tissue. The clinical differential diagnoses included Kaposi's sarcoma, melanoma, and hematoma. Dermatopathologists and dermatologists should be aware of this entity to avoid confusion with other benign and malignant neoplasms that may contain multinucleated giant cells. The distinguishing histologic and immunohistochemical features of this tumor are discussed.     

Giant cutaneous squamous cell carcinoma of the nose with subsequent brain extension

INTRODUCTION: Cutaneous squamous cell carcinoma is an invasive and destructive tumor, and may cause death by local extension or because of metastasis. We report the case of a patient with a giant squamous cell carcinoma of the nose and extension to the brain and discuss the main risk factors from this extension. OBSERVATION: Resection of a giant squamous cell carcinoma was performed of the nose in a 45 year-old man after debulking radiotherapy. Histological examination disclosed a well-differentiated tumor and perineural involvement, with at least a 6 mm margin. A first relapse occurred on the orbital edge of the initial resection, the lesion was removed revealing an involvement of the infra-orbital nerve. Whilst the patient was receiving chemotherapy, a second relapse occurred responsible for ophthalmoplegia and loss of vision, with involvement of the left orbital apex, cavernous sinus and temporal lobe. The patient died from grand mal seizures. DISCUSSION: Brain extension of cutaneous squamous cell carcinoma of the head is rare. It develops along the anatomic pathways, especially perineural spread. Main risk factors for such a poor course are discussed, including the size of tumor, the anatomic site, the depth and perineural invasion.     

播散性低分化腺癌并发印戒细胞癌皮肤转移

报告1例播散性低分化腺癌并发印戒细胞癌皮肤转移.患者男,23岁.躯干、头面部、四肢出现黄豆至鸽卵大结节2个半月,无自觉症状.皮损组织病理检查:真皮胶原纤维间及皮下组织内肿瘤细胞弥漫性浸润,真皮胶原纤维被破坏,肿瘤细胞体积较大,胞质略空,并见瘤巨细胞.免疫组化染色示LCA、CK7、CD138均(-),CK20( ).诊断:低分化腺癌并发印戒细胞癌皮肤转移.患者于皮肤转移癌出现后8个月死亡.