Cholesterotic fibrous histiocytoma. Its association with hyperlipoproteinemia.

A 63-year-old woman with fibrous histiocytomas showed cholesterol deposition in the setting of type IIB hyperlipidemia. The two lesions involved the left leg and right thigh. One had typical features of a fibrous histiocytoma including changes of the overlying epidermis. The other was essentially replaced by cholesterol deposits and could not be differentiated from a tuberous xanthoma. This case illustrates the histiocytic response of fibrous histiocytomas to a hyperlipoproteinemic microenvironment.

Origin and relationship between different cell types in malignant fibrous histiocytoma.

The derivation of histiocyte-like cells in malignant fibrous histiocytoma (MFH) has been a matter of debate. To shed light on this problem two cell lines from two subsequent recurrencies of MFH were established. The existence of two different cell populations, mainly fibroblast-like in the first cell line and mainly histiocyte-like in the second, was shown by light and electron microscopy, DNA measurements, and karyotype analysis. By detailed banding analysis and identification of several identical chromosomal marker types in the two cell lines, it was proven that they originally derived from the same single cell or single clone. Because the first cell line, with mainly fibroblast-like cells, was in the hypotriploid region and the second, with mainly histiocyte-like cells, was in the penta-hexaploid region, the data explained the appearance of histiocyte-like cells in MFH as a consequence of chromosomal progression.

Pulmonary sclerosing hemangioma of the lung. A type II pneumocytoma by immunohistochemical and immunoelectron microscopic studies.

Three cases of pulmonary sclerosing hemangioma were studied by immunohistochemical and immunoelectron microscopic methods using a panel of antibodies. Six cases of adenocarcinoma of the lung, three cases of normal mesothelium, and three cases of mesothelioma were used as controls. The cytoplasm of some of the sclerosing hemangioma tumor cells was positive for the anti-lung surfactant apoprotein monoclonal antibody (PE-10). These cells were the pale cells of the solid areas, the cells covering the papillary projections, and the cells lining the cleft-like spaces. These cells also were positive for conventional epithelial cell markers. Some cells also were positive for vimentin. Electron microscopic study showed that the predominant cell was a poorly differentiated pneumocyte. Immunoelectron microscopic study also demonstrated that PE-10 existed in the rough endoplasmic reticulum of some of the cells in the solid areas, in the same way as normal type II pneumocytes. We concluded that the sclerosing hemangioma is an epithelial tumor with differentiation towards type II pneumocytes.

Immunoreactivity for laminin and type IV collagen in malignant and benign fibrous histiocytoma.

Sixteen malignant fibrous histiocytomas (MFH) and ten benign fibrous histiocytomas of the skin were studied immunohistochemically for the distribution of two basement membrane (BM) proteins, laminin and type IV collagen, in order to evaluate their cellular nature. Linear staining for both proteins was present in the vascular BMs. Intracytoplasmic laminin was observed in the neoplastic fibroblast-like and pleomorphic giant cells in 11 MFHs. Two MFHs also showed similar staining for type IV collagen. In the giant cell subtype of MFH, the reactive giant cells were totally negative whereas the neoplastic cells were strongly positive for laminin. Extracellular fibres staining positively for both BM proteins were seen in two MFHs. Except for the capillary network, the benign fibrous histiocytomas were negative for laminin and type IV collagen. On the basis of the present results, we favour the concept that MFHs are primitive mesenchymal tumours, some of which may show histogenetic relationships with tumours of BM forming mesenchymal cells.

Angiomatoid malignant fibrous histiocytoma: flow cytometric DNA analysis of six cases.

Using flow cytometry, we examined the DNA content of six angiomatoid "malignant" fibrous histiocytomas (AMFH), seven nonangiomatoid MFH, and seven myxoid variants of MFH. All six AMFHs were diploid. All nonangiomatoid MFHs and six of seven of the myxoid variant were aneuploid. The clinical course, histological appearance, and ploidy pattern of AMFH are distinctly different from other MFH variants. These differences strongly suggest that AMFH is at the benign end of the clinicobiologic spectrum manifested by "malignant" fibrous histiocytomas.

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.

[Protein S-100 in spontaneous soft tissue and peripheral nerve neoplasms in rats]. / Belok S-100 v spontannykh opukholiakh miagkikh tkanei i perifericheskikh nervov krys.

16 spontaneous tumors of the peripheral nerves and 18 spontaneous tumors of mesenchymal origin in BDVI rats were studied by peroxidase-antiperoxidase method using anti-serum (DAKOPATT) against protein S-100. The majority of spontaneous peripheral nerve tumors were of cystic histological structure identical to that of cystic neurinomas induced in rats by ethylnitrosourea and almost all of these tumors were S-100 protein positive. The incidence of spontaneous neurinomas in BDVI rats was in some experiments as high as 5%. All tumors of mesenchymal origin (except one lipoma) were S-100 protein negative: 2 fibromas, 6 fibrosarcomas, 3 malignant fibrous histiocytomas, one rhabdomyosarcoma and one hemangioendothelioma. S-100 protein is found, as in human pathology, useful for distinguishing tumors of schwann cell and mesenchymal origin in rats.

Malignant peripheral nerve sheath tumors and spindle cell sarcomas: an immunohistochemical analysis of multiple markers.

An immunocytochemical study using a panel of commercially available antisera, has been performed to distinguish on the basis of their immunoreactivity a series of spindle cell sarcomas diagnosed solely on the histologic features: 11 malignant schwannomas (MS), 8 leiomyosarcomas (LMS) and 3 malignant fibrous histiocytomas (MFH). The results have been compared with those obtained in 12 benign and 8 malignant peripheral nerve sheath tumors (MPNST) in which the microscopic diagnosis was supported by their origin in a nerve trunk and/or in von Recklinghausen's (vR) disease. The following antisera were used: anti-S-100 protein, anti-Leu-7, anti-neuron specific enolase (NSE), anti-myelin basic protein (MBP), anti-glial fibrillary acidic protein (GFAP) and anti-actin. S-100 protein was present in 100% of benign and malignant peripheral nerve tumors and in 7/11 (63%) of MS diagnosed on histological basis only and in 3/8 (37%) LMS. MFH were negative. Leu-7 positivity was observed in 8/12 (66%) and 6/8 (75%), respectively, in benign and malignant PNS neoplasms, in 5/11 (45%) MS, 4/8 (50%) LMS and 2/3 (66%) MFH. NSE was present in 7/12 (58%) and 6/8 (75%), respectively, in benign and malignant PNS tumors, in 6/11 (54%) MS and in 1/8 (12%) LMS. MFH were negative. MBP resulted negative in peripheral nerve neoplasms and spindle cell sarcomas. GFAP positivity was observed in 2/12 (16%) and 1/8 (12%), respectively, in benign and malignant PNS neoplasms. All spindle cell sarcomas were negative. All cases of MPNST and spindle cell sarcomas showed actin immunoreactivity. These results indicate that: (1) MBP, Leu-7 and NSE do not represent markers of schwannian differentiation; (2) GFAP, although rarely expressed, may indicate schwannian differentiation, and (3) malignant peripheral nerve neoplasms and LMS share immunoreactivity for S-100, Leu-7, NSE and actin, therefore they cannot be differentiated on immunocytochemical basis using commercially available antisera.

Tc-99m diphosphonate uptake in malignant fibrous histiocytoma: a possible iron-related effect.

A man with malignant fibrous histiocytoma of the thigh had avid uptake of Tc-99m MDP in the lesion. Review of tissue sections showed considerable accumulation of iron in the tumor. Iron is known to be a potential nidus for deposition of the Tc-99m diphosphonates. A review was made of tissue sections from two other reported cases of malignant fibrous histiocytoma which also had significant accumulation of Tc-99m diphosphonates. Both revealed iron within the tumor. The origin of the iron is unknown (perhaps from necrosis and hemorrhage, from trauma, or from innate phagocytic activity of the histiocytes). However, this observation may serve as a stimulus to studies attempting to discern the underlying mechanisms of extraosseous deposition of the Tc-99m diphosphonates.

Malignant fibrous histiocytoma with epithelial differentiation?

A case of recurrent soft part sarcoma with focal areas showing epithelial differentiation in the right thigh in a 78-year-old woman is reported. The primary tumor consisted of myxoid areas and solid areas, in which relatively uniform epithelioid tumor cells were arranged in sheets, whereas pleomorphism and a storiform pattern appeared in the recurrent tumors. Thus this tumor was suspected to be a malignant fibrous histiocytoma. However, further studies showed unexpected ultrastructural and immunohistochemical features. Cytokeratin immunoreactivity and tonofilamentlike structures probably indicated epithelial differentiation of some tumor cells. From the clinical and histological findings, this tumor should be identified as a malignant fibrous histiocytoma with phenotypic expressions of epithelial cell.

Intracytoplasmic crystalloid structures in a malignant fibrous histiocytoma: ultrastructural and cytochemical study.

Crystalloid structures were frequently observed in the cytoplasm of the tumor cells of a malignant fibrous histiocytoma arising in the left leg of a 71-year-old female. These structures were located in the cytoplasm of the fibroblastlike and histiocyte-like tumor cells. The structures consisted of an aggregate of dense granules without unit membrane. Neither glycoproteins nor polysaccharides were detected in these structures on sections stained with chromic acid-phosphotungstic acid or periodic acid-thiocarbohydrazide-silver proteinate. On sections from acrylate-embedded specimens, the structures were easily digested by trypsin and protease but were not sensitive to RNase. Although the significance and origin of these structures remain obscure, the results indicate that the crystalloid structures in the present study are mainly composed of proteinaceous substance.

Postirradiation malignant fibrous histiocytoma expressing cytokeratin. Implications for the immunodiagnosis of sarcomas.

A malignant fibrous histiocytoma of the sacrum complicating the course of radiation therapy for endometrial carcinoma is presented. Although the tumor fulfilled the clinical, radiologic, and histologic criteria for a postirradiation malignant fibrous histiocytoma of bone, it also expressed cytokeratin. That this immunoreactivity reflected keratin synthesis by the tumor and not an unusual pattern of cross-reactivity with another intermediate filament such as vimentin is strongly suggested by the reproducibility of the immunoreactivity utilizing both polyclonal and monoclonal antibodies and extinction of the immunoreactivity following absorption of the primary antiserum with keratin proteins. This is the first reported instance of keratin expression by a malignant fibrous histiocytoma; it indicates that sarcomas apart from synovial sarcoma and epithelioid sarcoma may sometimes express this protein.

Flow cytometric DNA analysis of malignant fibrous histiocytoma and related fibrohistiocytic tumors.

Fibrohistiocytic neoplasms with similar histologic characteristics may have vastly different biologic behaviors. We studied 23 fibrohistiocytic tumors to determine if cellular DNA content was correlated with clinical outcome. Archival paraffin blocks of 9 malignant fibrous histiocytomas (MFH), 3 dermatofibrosarcoma protuberans, 9 dermatofibromas, 1 juvenile xanthogranuloma, and 1 nodular fasciitis were processed, stained with propidium iodide, and analyzed by flow cytometry. Five of 9 (56%) MFH and 1 of 3 (33%) dermatofibrosarcoma protuberans were aneuploid. All 11 benign fibrohistiocytic tumors were diploid. Local recurrence occurred in 3 of 5 (60%) cases of aneuploid MFH, but in none with a diploid MFH tumor. No cases of dermatofibrosarcoma protuberans or benign tumors recurred. Aneuploidy was associated with decreased survival, as 2 of 5 patients with aneuploid MFH died within 1 year of diagnosis whereas all 4 patients with diploid MFH tumors are alive after an average follow-up of 4 years (range, 1 to 11). The diploid and aneuploid groups did not differ in clinical stage at the time of diagnosis. Our results indicate that retrospective DNA analysis can detect aneuploidy in both MFH as well as other fibrohistiocytic tumors, and that aneuploidy in MFH may place the patient at increased risk for local recurrence and mortality.

[Immunohistochemical detection of lysozyme and alpha-1-antichymotrypsin in fibrohistiocytic tumors]. / Immunhistochemischer Nachweis von Lysozym und Alpha-1-Antichymotrypsin in fibrohistiozyhtären Tumoren.

Lysozyme and alpha-1-antichymotrypsin depositions were recorded by means of the PAP technique from benign and malignant fibrohistiocytic tumours. These depositions were seen in relation to lesions with histiocytic reactions. The findings indicate that the detection of these markers support the solution of problems of differential diagnosis. An important role is particularly played by demonstration in fibroblastic elements within the neoplasm proper. The results also suggest the possible existence of an undifferentiated precursor cell.

Diagnosis, staging, and treatment of juvenile nasopharyngeal angiofibroma (JNA).

Nineteen patients with juvenile nasopharyngeal angiofibroma (JNA) were surgically treated with different techniques from January 1968 through December 1985. Two patients had undergone a previous operation at another hospital; all patients were males (mean age 15.4), and the most common symptom was nasal obstruction (84.2%). Lateral extension into the pterygomaxillary fossa occurred in 14 patients (73.6%), and 2 also had intracranial invasion (10.5%). In five cases, the tumor's cytosol was analyzed for hormonal receptors. Negative values for estrogen and progesterone receptors were obtained, although the content of dehydrotestosterone receptors was highly positive. These results tend to support the hypothesis of JNA's androgen-dependence. The authors emphasize the need of a preoperative staging classification based on clinicoradiological data in selecting the most adequate surgical approach. Tumors with lateral extension into the pterygomaxillary fossa can be easily removed through a midface degloving; large involvement of the infratemporal fossa requires, also, a transzygomatic dissection. In JNAs with intracranial extension a combined intracranial-extracranial approach is advisable.