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PubMed2005

Nuclear beta-catenin expression distinguishes deep fibromatosis from other benign and malignant fibroblastic and myofibroblastic lesions.

Deep fibromatoses (desmoid tumors) are clonal myofibroblastic proliferations that are prone to aggressive local recurrences but that do not metastasize. They must be distinguished from a host of fibroblastic and myofibroblastic lesions as well as from smooth muscle neoplasms. Virtually all deep fibromatoses have somatic beta-catenin or adenomatous polyposis coli (APC) gene mutations leading to intranuclear accumulation of beta-catenin. Since low-grade sarcomas in general lack beta-catenin and since reactive proliferations would not be expected to have it, we predicted that nuclear beta-catenin expression would be detected in deep fibromatoses but absent in other entities in the differential diagnosis. We evaluated the role of beta-catenin to help differentiate distinguish deep fibromatoses from congeners. Formalin-fixed, paraffin-embedded sections from 21 lesions from 20 patients with deep fibromatoses were stained with monoclonal beta-catenin antibody (Transduction Laboratories) and compared with low-grade fibromyxoid sarcoma (n=12), leiomyosarcoma (n=10), various other fibrosarcoma variants (n=13, including 3 myofibrosarcomas, 3 sclerosing epithelioid fibrosarcomas, 5 low-grade fibrosarcomas, 1 classic fibrosarcoma arising in dermatofibrosarcoma protuberans, 1 inflammatory myxohyaline tumor/myxoinflammatory fibroblastic sarcoma), myofibroma/myofibromatosis (n=12), nodular fasciitis (n=11), and scars (n=9). Nuclear and cytoplasmic staining was assessed. All 21 examples of deep fibromatosis displayed nuclear beta-catenin (focal nuclear staining in one case to 90% staining). All other lesions tested (n=67) lacked nuclear labeling for beta-catenin, showing only cytoplasmic accumulation. beta-Catenin immunohistochemistry separates deep fibromatosis from entities in the differential diagnosis, a finding that can be exploited for diagnosis. Most fibromatoses have diffuse nuclear staining although occasional examples only focally label.

Adolescent↗

PubMed2004

HSP47 is a useful marker for skin fibroblasts in formalin-fixed, paraffin-embedded tissue specimens.

AIM: This study was undertaken to assess whether heat-shock protein (HSP)47 is a useful cell marker for skin fibroblasts in formalin-fixed, paraffin-embedded skin specimens. BACKGROUND: HSP47, a 47-kDa HSP, is a collagen-specific molecular chaperone localized in the endoplasmic reticulum. HSP47 plays an essential role in collagen biosynthesis in skin fibroblasts. METHODS: Immunohistochemistry was performed to detect HSP47 in skin fibroblast cultures and skin tissue sections. RESULTS: Immunostaining for HSP47 clearly detected skin fibroblasts in paraffin tissue sections as well as in fibroblast cultures and frozen tissue sections. HSP47 staining on paraffin sections from diseased skin specimens revealed that skin ulcer, keloid, nodular fascitis, spindle cell lipoma, and dermatofibroma had strong signals for HSP47 compared with the signals obtained from normal skin. Dermatofibrosarcoma protuberans had many HSP47 positive cells, but signals on individual cells were not as strong as those seen from the above benign proliferative disease samples. In neurofibroma, a small number of faintly positive cells were detected. Our double-immunostaining studies also demonstrated that HSP47 staining distinguished skin fibroblasts from CD68-positive histiocytes/macrophages, factor VIII-related antigen-positive endothelial cells, or factor XIIIa-positive dermal dendritic cells. CD34-positive interstitial cells coexpressed HSP47 in spindle cell lipoma. CONCLUSIONS: These findings indicate that HSP47 staining can detect skin fibroblasts in routine, paraffin-embedded specimens. A panel approach using HSP47 and other cell markers on paraffin sections may help the identification of the cell type involved with mesenchymal proliferative disorders.

Biomarkers↗

PubMed2005

Granular cell atypical fibroxanthoma.

We report on two patients with granular cell atypical fibroxanthoma. Both neoplasms were solitary, light-tan, dome-shaped papules on sun-exposed areas of the head in two elderly white men. Microscopically, these neoplasms showed a dermal proliferation of pleomorphic granular cells with irregular hyperchromatic nuclei, multinucleated cells, and scattered mitoses. Immunohistochemical stains were positive for CD68 and vimentin and negative for Melan-A or human melanoma black (HMB)-45, S-100 protein, pancytokeratin, and actin, consistent with atypical fibroxanthoma. The differential diagnosis of granular cells in neoplasms containing cytological pleomorphism is challenging in view of the many different neoplasms that may present with granular cytoplasm. These include the conventional granular cell tumor and its malignant form, leiomyoma, leiomyosarcoma, dermatofibroma, dermatofibrosarcoma protuberans, and angiosarcoma.

Aged↗

PubMed2005

The chemoresistance gene ABCG2 (MXR/BCRP1/ABCP1) is not expressed in melanomas but in single neuroendocrine carcinomas of the skin.

BACKGROUND: As the molecular mechanisms in melanoma chemoresistance remain unknown to date, we hypothesized these tumors to express the ATP-binding cassette (ABC) transporter G2 (ABCG2/MXR/BCRP1/ABCP1), a recently detected membrane transporter and putative stem-cell marker. Besides melanoma, we addressed the neuroendocrine carcinoma of the skin (Merkel cell carcinoma), another cutaneous cancer supposed to originate from neuroectoderm and usually chemoresistant. METHODS AND RESULTS: Upon semiquantitative reverse transcription polymerase chain reaction, ABCG2 mRNA expression was not upregulated in 18 melanoma resection specimens when compared with 19 acquired melanocytic nevi from which melanomas are known to often arise (Mantel-Haenszel test, p=0.3). At protein level, immunohistochemistry was negative in all 66 investigated melanoma resection specimens (50 primary melanomas and 16 cutaneous/subcutaneous metastases) and in 19 acquired melanocytic nevi. Among 29 neuroendocrine carcinomas of the skin, ABCG2 protein was detected in single clusters of cells in three tumors. As a positive control, three dermatofibrosarcomas were also stained and showed ABCG2 protein expression of the endothelial cells of the blood vessels. CONCLUSION: Altogether, chemoresistance of melanomas and neuroendocrine carcinomas of the skin cannot be explained by expression of the ABCG2-chemoresistance gene. Most of these tumors do not exhibit this potential stem-cell feature.

ATP Binding Cassette Transporter, Subfamily G, Mem↗

PubMed2006

CD44 and hyaluronate expression in follicular mucinosis.

BACKGROUND: CD44 is a membrane glycoprotein and the major cell-surface receptor of hyaluronate (HA). Lack of CD44 expression in mouse epidermis leads to an abnormal HA accumulation in the dermis, indicating an important role of CD44 in local HA metabolism. Decrease of epidermal CD44 expression in patients of lichen sclerosus et atrophicus is potentially responsible for dermal deposition of HA in this disease. Stromal HA accumulation is associated with decreased or lost expression of CD44 in perifollicular solitary cutaneous myxoma, myxoid dermatofibroma, and dermatofibrosarcoma protuberans. METHODS: We examined the expression of CD44 and HA in the skin biopsy specimens of 10 patients with follicular mucinosis by using CD44-specific antibodies and biotinylated HA-binding protein (HABP), respectively. RESULTS: No difference of CD44 expression was observed in the follicular keratinocytes when compared with those of unaffected interfollicular epidermis. The follicular zones of mucin deposition were strongly positive for HA. A weak interkeratinocyte staining for HA was also observed in the interfollicular epidermis. However, HABP staining revealed a stronger reactivity in the follicular keratinocytes surrounding the mucin-accumulated areas compared to the interfollicular keratinocytes. CONCLUSION: Our results suggest an active secretion of HA by follicular cells in follicular mucinosis.

Adult↗

PubMed1992

Comparative study of Ki-67 immunostaining and nuclear DNA content in histiofibrous tumors.

A comparative assessment was made of dermatofibroma, dermatofibrosarcoma protuberans, and malignant fibrous histiocytoma. The study was comprised of an immunohistochemical investigation using the Ki-67 monoclonal antibody and a quantitative analysis of cell nuclear DNA using flow cytometry. It was found that the index of Ki-67 monoclonal antibody labeling, the histogram pattern, and DNA index correlated with clinical malignancy, suggesting the usefulness of these indices for differential diagnosis and evaluation of prognosis.

Adult↗

PubMed1993

Nuclear DNA content and distribution of Ki-67 positive cells in nodular fasciitis.

Nodular fasciitis (NF) is regarded as a disease of reactive growth of fibroblasts, although it frequently shows clinically rapid growth and sometimes has to be histologically discriminated from fibrosarcoma. In order to confirm the position of NF as a benign tumor, we studied 5 cases of NF by a quantitative analysis of the nuclear DNA content using flow cytometry in paraffin-embedded specimens. In 3 of the 5 cases, an immunohistochemical study using Ki-67 monoclonal antibody was also conducted in frozen sections. In the analysis of nuclear DNA content, DNA histograms showed a diploid pattern in all cases, and G1, S and G2 + M periods were calculated as 96.7%, 2.5% and 0.8% (on the average), respectively. Although the labeling index of Ki-67 antibody (positive cells/tumor cells; %) was as scattered as 1.3-7.8 (5.6 on the average), the mean value was higher than that in already reported dermatofibroma and dermatofibrosarcoma protuberans and lower than that in malignant fibrous histiocytoma. These results endorse the hypothesis that NF is a reactive benign disease and reflect the biological behavior of this disease, which may frequently show rapid growth.

Adult↗

PubMed1996

A case of cutaneous malignant fibrous histiocytoma.

A 54-year-old Japanese man with cutaneous malignant fibrous histiocytoma on the back is reported. He not only had a past history of thyroid cancer 1 year prior to the onset of the skin tumor, but also had simultaneous bladder cancer. Despite the early, wide resection, the prognosis was rapid and progressive. Histologically, the primary lesion of the skin tumor was difficult to differentiate from dermatofibrosarcoma protuberans; however, the recurrent and the metastatic lesions changed in appearance.

Fatal Outcome↗

PubMed1999

A case of Werner's syndrome associated with osteosarcoma.

We described a case of Werner's syndrome associated with osteosarcoma. A 37-year-old Japanese man was diagnosed as having Werner's syndrome by the presence of juvenile cataracts, skin sclerosis and hyperpigmentation of the feet, high-pitched voice, characteristic bird-like appearance of the face with beak-shaped nose, thinning of the entire skin and hyperkeratoses on soles, hyperlipemia, hyperuricemia, diabetes melitus, and the mutated responsible gene (WRN). He had a 3-month history of a tumor on his left forearm. Histologically, the tumor included four histological patterns; a malignant fibrous histiocytoma-like, a desmoid-like, a dermatofibrosarcoma protuberans-like, and a chondrosarcoma-like pattern. Tumoral osteoid formation was also found in the tumor. Therefore, the tumor was diagnosed as osteosarcoma.

Adult↗

PubMed1989

Histiocytoma cutis: a tumour of dermal dendrocytes (dermal dendrocytoma).

The histogenesis of histiocytoma (dermatofibroma) was investigated using new antibodies that demonstrate factor XIIIa (FXIIIa) positive cells and the monocyte macrophage cell series (MAC 387), in formalin fixed tissue. The distribution of S100 protein, vimentin and Ulex europaeus agglutinin I (UEA-I) were also studied. The antibody against FXIIIa labelled the normal dermal population of fixed connective tissue cells (dermal dendrocytes) emphasizing their dendritic processes; cells that are widely distributed, but are most numerous in the papillary dermis. In contrast, the antibody, MAC 387 against monocyte derived macrophages, did not label this cell population. In 30 histiocytomas, intense labelling for FXIIIa was found peripherally, but labelling was rather weaker in cells situated centrally. Only a few cells labelled for S100 protein and with the monoclonal antibody MAC 387, but vimentin positivity was universal. UEA-I labelled only vessels in histiocytomas. However, FXIIIa labelling was negative in 16 dermatofibrosarcomas, three keloids and several other fibroproliferative lesions. These contrasting results with FXIIIa labelling have practical implications for diagnosis of benign and malignant spindle cell tumours of the skin. We conclude that histiocytomas (dermal dendrocytomas) take their origin from dermal fixed connective tissue cells, (dermal dendrocytes), but other spindle cell tumours may differ in histogenesis.

Dendritic Cells↗

PubMed1993

Dermatomyofibroma: additional observations on a distinctive cutaneous myofibroblastic tumour with emphasis on differential diagnosis.

Following the very recent description of a benign plaque-like myofibroblastic tumour of the skin, known as dermatomyofibroma, we present four further cases, emphasizing its clinical features and its histological differential diagnosis. Three patients were adult females and one was a boy. Two of the lesions arose on the anterior abdominal wall, one on the shoulder, and one on the neck. Clinically, there was often close resemblance to a keloid. Follow-up revealed no evidence of recurrence after simple excision. Histologically, these were non-encapsulated but well-circumscribed, plaque-like lesions located in the reticular dermis, and composed of fascicles of monomorphic myofibroblasts, orientated parallel to the skin surface. Immunohistochemically, most of the tumour cells expressed alpha-smooth-muscle actin. The principal differential diagnosis is plaque-stage dermatofibrosarcoma protuberans. Other differential diagnoses include diffuse neurofibroma, dermatofibroma and other myofibroblastic skin tumours.

Actins↗

PubMed2004

Immunohistochemical staining of cutaneous tumours with G-81, a monoclonal antibody to dermcidin.

BACKGROUND: Recently, the novel antimicrobial peptide named dermcidin (DCD) was reported in human eccrine sweat glands. OBJECTIVES: We investigated the expression of DCD in a variety of cutaneous tumours in order to assess the usefulness of the monoclonal antibody (G-81), which recognizes a fragment of DCD. PATIENTS/METHODS: We studied the immunoreactivity of the G-81 antibody on 197 cutaneous tumours. RESULTS: A total of 13 of 26 cutaneous mixed tumours showed substantial immunoreactivity. In contrast all the following cases were completely unreactive: (i) epithelial tumours (seborrhoeic keratosis, squamous cell carcinoma, Bowen's disease, actinic keratosis, genital Paget's disease); (ii) follicular tumours (basal cell carcinoma, trichilemmoma, trichoepithelioma, trichoblastoma, keratoacanthoma, proliferating trichilemmal tumour, pilomatricoma); (iii) melanocytic tumours (malignant melanoma, naevus cell naevus, Spitz naevus, blue naevus); (iv) neural tumours (schwannoma, neurofibroma, Merkel cell neoplasm); (v) mesenchymal tumours (soft fibroma, dermatofibroma, dermatofibrosarcoma protuberans, vascular leiomyoma, leiomyosarcoma, lipoma, juvenile xanthogranuloma, angiomyoma); and (vi) other sweat gland tumours (poroid neoplasms, syringoma, cylindroma, clear cell hidradenoma, spiradenoma, syringoid eccrine carcinoma, mucinous carcinoma, apocrine cystadenoma, syringocystadenoma papilliferum, apocrine adenocarcinoma). Twenty-six cutaneous mixed tumours were considered from histopathological findings to be the apocrine type, but 13 of 26 mixed tumours contained some DCD-immunopositive cells that possibly differentiate into eccrine secretory glands. CONCLUSIONS: We found the expression of DCD in tubular structures of 50% of cutaneous mixed tumours with apocrine differentiation. These results suggest that a number of cutaneous mixed tumours show both eccrine and apocrine differentiation in the same neoplasm.

Antibodies, Monoclonal↗

PubMed2005

Cytomorphological study of soft tissue neoplasms: role of fluorescent immunocytochemistry in diagnosis.

OBJECTIVES: Exact categorization of soft tissue tumours (STTs) on smears requires application of various ancillary techniques. This study was aimed at evaluating the role of fluorescent immunocytochemistry (FICC) in cyto-diagnosis of 30 STT cases. METHODS: Thirty cases of soft tissue tumours were included in the present study. All cases were subjected to routine Giemsa and Papanicolaou stain. Extra smears were made and kept for fluorescent immunostaining. A panel of cytoskeletal antibodies, tagged with FITC (Fluorescein isothyocynate), was employed in all these cases. Fluorescent immunostained smears were examined under Zeiss Confocal Laser scanning microscope, using double immunofluorescence (red-green). Finally, all cases were subjected to biopsy and again immunoperoxidase staining. RESULTS: Among the 30 cases in the present study, unaided cytological diagnoses ranged from 'spindle cell' tumour in four (13.3%) cases, benign and malignant spindle cell tumour in 17 (56.6%) cases, to malignant mesenchymal tumour in nine (30%) cases. FICC helped in further correct categorization of 25/30 (83.3%) cases viz. leiomyoma (three), benign neurogenic tumour (six), schwannoma (one), dermatofibrosarcoma protuberans (three), synovial sarcoma (two), rhabdomyosarcoma (two), malignant fibrous histiocytoma (five) and malignant peripheral nerve sheath tumour (three). Aggressive fibromatosis was found to be a missed diagnosis in two cases. Overall concordance between cyto-diagnosis with FICC, and histopathology results was 83.3% (P < 0.05). CONCLUSION: Fluorescent immunocytochemistry is a significant ancillary technique for making a rapid and specific diagnosis of STT, as required for their timely management. Incorporation of a wide panel of antibody markers with clinico-cytological correlation is recommended in forming an exact diagnosis in these cases.

Biopsy, Fine-Needle↗

PubMed1987

Atypical fibroxanthoma of the skin: a clinicopathological and immunohistochemical study and a discussion of its histogenesis.

The morphological and immunohistochemical characteristics of 37 atypical fibroxanthomas of the skin were examined. Twenty-four tumours were nodular ulcerative lesions on the head and face of patients with a median age of 75 years, whereas 13 tumours occurred on the trunk and limbs of patients with a median age of 48 years. Both pleomorphic polygonal and giant cells as well as the spindle cell component of the tumours stained for the histiocytic markers alpha 1-antichymotrypsin, alpha 1-antitrypsin, lysozyme and, less frequently, for ferritin. Leu M1 antigen and peanut agglutinin receptors were not demonstrable in tumour cells. This antigenic profile was contrasted with the findings in six cases of dermatofibroma which were largely not reactive with the antisera used. The immunohistochemical findings in atypical fibroxanthomas suggest that they represent a homogeneous group of tumours which are related to tissue histiocytes. These results are discussed in the context of the published findings in other so-called fibrohistiocytic tumours including dermatofibrosarcoma protuberans and malignant fibrous histiocytoma. The diagnoses in three cases coded as atypical fibroxanthomas were revised on the basis of their showing a different immunohistochemical profile.

Adult↗

PubMed1984

Enzyme histochemical observation of fibrohistiocytic tumors.

The reactivity of lysosomal enzymes in 17 fibrohistiocytic tumors were examined histochemically to evaluate the histiocytic nature of the tumors. The lysosomal enzymes examined were acid phosphatase (Ac-P), non-specific esterase (NS-E), beta-glucuronidase (beta-GL), and N-acetyl-beta-glucosaminidase (N-GA). The tumors examined were eight malignant fibrous histiocytomas (MFH) (i.e., five common types, two myxoid types, and one inflammatory type), one atypical fibroxanthoma of the skin (AFX), one dermatofibrosarcoma protuberans (DFSP), two giant cell tumors of the tendon sheath (GCT), and five dermatofibromas (DF). Seven of 8 MFH showed strong reactivity for all enzymes examined. Positive reactions were seen as evenly distributed granules in the cytoplasm of fibroblastic, histiocytic and giant cells in all types of the tumors. Almost all AFX, GCT, and DF showed moderate to strong reactivity. These findings suggest that these tumors were composed of cells with the enzymatic character of histiocytes. However, DFSP contained no cells giving a positive reaction, and thus its histiocytic nature could not demonstrated.

Acetylglucosaminidase↗

PubMed1989

Treatment of malignant fibrous histiocytoma and atypical fibrous xanthomas with micrographic surgery.

Fibrous tumors of the soft tissue are usually benign, but some fibrous neoplasms such as dermatofibrosarcoma protuberans (DFSP), atypical fibroxanthoma (AFX), and malignant fibrohistiocytoma (MFH) can be very destructive locally with a high recurrence rate after local excision. On occasion, they can metastasize. Previous reports have confirmed the high success rate of Mohs micrographic surgery for the treatment of DFSP, but data have been lacking on the potential benefit of this surgical approach for MFH and AFX tumors. Over the past 6 years, we have treated 17 patients with MFH (20 tumors) and 5 patients with AFX with Mohs micrographic surgery. A retrospective analysis of the surgical results is presented. To date (average 3-year follow-up), all patients contacted are tumor free with only one recurrence; no patient has developed metastatic disease. Our results to date are very encouraging; they lend support to Mohs micrographic surgery as a desired surgical approach for these difficult-to-cure neoplasms.

Adolescent↗

PubMed1997

Malignant melanomas simulating various types of soft tissue tumors.

BACKGROUND: Primary malignant melanomas, recurrences, and metastases thereof can present with a wide variety of clinicopathologic aspects. OBJECTIVE: The present series describes eight primary malignant melanomas and/or 10 local recurrences/metastases (from eight patients) misdiagnosed as various types of soft tissue tumors: two dermatofibrosarcoma protuberans, two atypical fibroxanthomas, two storiform-pleomorphic malignant fibrous histiocytomas, one myxofibrosarcoma ("myxoid malignant fibrous histiocytoma"), two malignant hemangiopericytomas, and nine malignant schwannomas. METHODS: In three cases correct diagnosis was established by clinicopathologic correlation during follow-up; all the others were only discovered during a retrospective work-up of all soft tissue tumors diagnosed at the Dermatohistopathological Laboratory of the Department of Dermatology, University of Innsbruck. RESULTS: Helpful clues derived from subtle intraepidermal, irregular spread of melanocytes, focal nested arrangement of tumor cells, sparse melanin deposition, neurotropism, and prominent peripheral lymphohistiocytic response, partially forming lymph follicles. Besides clinicopathologic correlation, histology of serial sections as well as immunohistochemistry (S100 protein more important than NK1/C3; HMB45 without benefit) and electron microscopy (melanosomes) proved helpful for definitive diagnosis. In contrast to the general assumption that spindle cell/desmoplastic malignant melanomas have an unequivocal bad prognosis, our series, as well as evidence from the literature, document a better prognosis than that of other types with comparable tumor thickness (70% vs 50% 5-year survival). Moreover, labeling with E9, an antimetallothionein marker, confirmed its usefulness for prognosis being strongly positive in primary lesions followed by rapid progression, but mostly negative in those without. CONCLUSION: These cases document that malignant melanoma may mimic various types of soft tissue tumors; correct interpretation is important as prognosis and therapeutic management differ considerably between these entities.

Aged↗

PubMed2004

Myofibrosarcoma treated with Mohs micrographic surgery.

BACKGROUND: Myofibrosarcoma is a rare malignant mesenchymal tumor composed predominantly of differentiated myofibroblasts. These tumors occur in both children and adults alike and are most commonly located on the head and neck. Recurrences rates range from 44% to 75%, and metastatic disease has been reported in up to 44% of cases. OBJECTIVE: The objective was to present a case of a myofibrosarcoma treated with Mohs micrographic surgery and discuss the use of ultrastructural evaluation in the diagnosis of this rare tumor. METHODS: A 31-year-old African American woman who presented to the Emory University Dermatologic Surgery Clinic with a 4-month history of a 2.5 x 2.5-cm indurated firm painful right upper lateral thigh nodule. A prior biopsy revealed a proliferation of somewhat bland spindled cells with large zones of necrosis with prominent mitotic figures, changes compatible with a cellular dermatofibroma. Because the lesion exhibited clinically suspicious characteristics such as rapid growth and deep infiltration, the patient was subsequently referred to Emory for further evaluation. There was no evidence of lymphadenopathy and a chest X-ray was unremarkable. RESULTS: A two-staged (five and four sections, respectively) uneventful Mohs micrographic surgery procedure was performed resulting in a defect measuring 3.5 x 3.5 x 1.0 cm. Primary closure was achieved with no complication, and the final scar measured 10 cm. Because of the suspicious clinical behavior of this tumor debulking specimen was sent for permanent section. Histopathologic interpretation of these sections was consistent with a fibrosarcoma with myofibroblastic differentiation. No clinical recurrence noted after 14-month follow-up. CONCLUSION: Mohs micrographic surgery is a technique that has been shown to provide superior cure rates in the treatment of many mesenchymal tumors. Here, we report the first case of myofibrosarcoma treated with Mohs micrographic surgery. Myofibrosarcoma is a rare but aggressive tumor that can be difficult to distinguish from other somewhat less aggressive malignancies such as dermatofibrosarcoma protuberans or malignant fibrous histiocytoma. Specific histopathologic criteria are reviewed. We recommend including Mohs micrographic surgery in the armamentarium for the treatment of this rare tumor.

Adult↗