Immunohistochemistry of capillary hemangioblastoma. Immunoperoxidase-labeled antibody staining resolves the differential diagnosis with metastatic renal cell carcinoma, but does not explain the histogenesis of the capillary hemangioblastoma.

We used a battery of antigens to determine whether immunohistochemistry can (a) contribute to resolving the histogenesis of the stromal component of the capillary hemangioblastoma, and (b) answer cases of difficult pathologic differential diagnosis with metastatic clear cell carcinoma. The stromal cells of the capillary hemangioblastoma are antigenically polymorphous and may express immunoreactive erythropoietin, renin, keratin, Leu M1, Leu 7, actin, neuron-specific enolase, S100 protein, and glial fibrillary acidic protein. However, the use of epithelial membrane antigen allows certain histopathologic distinction between capillary hemangioblastoma and metastatic clear cell carcinoma.

Autocrine tumour growth regulation by somatomedin C: an in-vitro model.

A human primary haemangiosarcoma was derived from a patient with severe hypoglycaemia. Cell line established from that tumour secreted somatomedin C in serum-free culture media. Immunoreactive somatomedin from the media eluted from Sephacryl S-200 in two peaks of 160 000 and 8000 molecular weights. Similar results were obtained when medium was acidified and chromatographed on Sephadex G-50. Binding of tracer concentrations of 125I-labelled somatomedin C to human haemangiosarcoma cells was much higher than that of 125I-labelled insulin. Half-maximal displacement of 125I-labelled somatomedin C binding occurred at an unlabelled somatomedin C concentration of 0.7 nmol/l. Insulin competed with 125I-labelled somatomedin for binding to this receptor, but 150-fold more insulin was required for half-maximal displacement. Somatomedin secreted by human haemangiosarcoma cells and purified from serum-free media strongly stimulated [methyl-3H]thymidine incorporation into the DNA of these cells. Inhibition of somatomedin C secretion by cortisol resulted in the inhibition of tumour cell proliferation but stimulation of somatomedin secretion by human GH stimulated the cell proliferation rate. It appears that production of somatomedin C in human haemangiosarcoma cells plays a part in the regulation of tumour growth by an autocrine mechanism.

Angiosarcoma of the thyroid: a light, electron microscopic and histoimmunological study.

A histologic, histoimmunological, and ultrastructural study of a primary angiosarcoma of the thyroid gland is reported. The occurrence of neoplastic cells positive for Factor VIII-related antigen and Ulex Europaeus Agglutinin-I and the presence in their cytoplasms of Weibel-Palade bodies are consistent with this diagnosis. These findings further support the view that primary angiosarcoma of the thyroid is a distinct pathological entity and should no longer be interpreted as a variant of a poorly differentiated carcinoma.

Cytokeratin expression in epithelioid vascular neoplasms.

Seven epithelioid and eight non-epithelioid vascular tumors were studied by the avidin-biotin-peroxidase method for the presence of endothelial- and epithelial-associated markers, using Ulex europaeus agglutinin-1 (UEA-1) lectin, and antibodies directed against factor VIII-related antigen, (FVIII-RA), vimentin, keratin, carcinoembryonic antigen, and epithelial membrane antigen. The cases included four epithelioid hemangiomas, two epithelioid hemangioendotheliomas (EHE), one epithelioid angiosarcoma (EAS), four common non-epithelioid capillary hemangiomas, and four non-epithelioid angiosarcomas. Staining for FVIII-RA, UEA-1, and vimentin were observed in all cases. The EAS showed staining for keratin in formalin-fixed, paraffin-embedded sections and in frozen sections. Staining for keratin was also observed in frozen sections of one EHE. Both keratin-positive vascular tumors were confirmed with electron microscopy. Carcinoembryonic antigen and epithelial membrane antigen stains were negative in all cases. Our results show that the epithelioid vascular tumors EHE and EAS, in addition to staining for the endothelial markers and vimentin, may also express the epithelial marker keratin. This is important since these tumors may closely resemble carcinomas by routine light microscopy. This study further underscores the importance of using a broad panel of immunohistochemical markers in the diagnostic workup of soft-tissue neoplasms.

Capillary hemangioblastoma. An immunohistochemical study.

Previous studies using immunohistochemical methods to determine the presence of glial fibrillary acidic protein (GFAP) and Factor VIII-related antigen (FVIIIR:Ag) in stromal cells of capillary hemangioblastomas have yielded conflicting results with respect to the possible astrocytic and endothelial origins of these cells. This study included Ulex europaeus I lectin (UEAI), a more sensitive marker of endothelial cells. Antibodies were also used as markers of pericytes and a variety of markers were employed to identify different populations of histiocytes. Results of this investigation indicate that FVIIIR:Ag and UEAI are limited only to endothelial cells, and that GFAP is present in entrapped astrocytes only. Positivity of stromal cells was found with some of the histiocytic markers, but the authors were unable to conclude that these cells have a histiocytic origin. It was concluded that currently there is no evidence that stromal cells are derived from endothelial, pericytic, or astrocytic cells-their origin remains uncertain.

Differentiation of metastatic breast carcinoma from Stewart-Treves angiosarcoma. Use of anti-keratin and anti-desmosome monoclonal antibodies and factor VIII-related antibodies.

A chronic brawny edema developed in the shoulder and arm ipsilateral to the site of a previous mastectomy in a 68-year-old woman. Bluish nodules and telangiectasia admixed with more superficial papules and plaques developed subsequently. Histologically, many of these lesions showed angiocentric clusters of large hyperchromatic tumor cells, often with lumina in the center. It was difficult to differentiate two possibilities, ie, postmastectomy angiosarcoma in lymphedema (Stewart-Treves syndrome) and nodulotelangiectatic metastasis of the original breast carcinoma. Monoclonal anti-keratin antibody and anti-desmosome antibody identified keratin and desmosomes in the tumor cells, whereas staining with factor VIII-related antigen yielded negative results. Electron microscopy revealed, in addition to keratin filaments and desmosomes, typical secretory cells and lumen formation. A combined use of specific monoclonal and polyclonal antibodies is helpful in the determination of tumor origins.

Microgravimetric analysis of human brain tissue: correlation with computerized tomography scanning.

Microgravimetric technique was used to measure the water content of tumors and adjacent brain. Multiple 1-cu mm samples were obtained from 17 patients with neurosurgical lesions. The site of each sample was located on the appropriate computerized tomography (CT) slice, and the water content correlated with the CT attenuation coefficient. The water content of peritumor white matter in 11 patients with glioblastomas was 5% to 8% H2O/gm tissue greater than the water content of white matter measured in three normal control individuals. These areas corresponded to low CT attenuation coefficients (8 to 15 EMI units). There was no statistically significant differences between the water content of tumors and adjacent white matter, even though the CT attenuation coefficient of the tumor was often at higher value. Low CT attenuation coefficient areas surrounding meningioma, metastasis, and lymphoma always correlated with elevated water content. The greatest water content (84.7% H2O/gm tissue) was found in the white matter surrounding an arteriovenous malformation. There was no correlation between the CT attenuation coefficient of this tissue and the water content in the arteriovenous malformation. This study shows that areas of low CT attenuation coefficient may correlate with measurements of the water content of tissue, but that increased water content may exist without demonstrable changes in the CT attenuation coefficient.

Angiosarcoma of the heart in an adolescent. A light and electron microscopic and immunohistochemical study.

A cardiac angiosarcoma occurred in the right atrium of a 15-year-old boy. Unusual features included the patient's young age and the antemortem pathologic diagnosis of the tumor.

Flow fluorescence cytometry of deoxyribonucleic acid in meningiomas: studies on surgically removed tumor specimens compared with their cells in primary tissue cultures.

Flow cytometric deoxyribonucleic acid analysis was carried out in 15 meningiomas obtained surgically: two were fibroblastic; one was transitional; four were syncytial with few or no mitoses; three were angioblastic; three were syncytial containing many mitoses and focal micronecroses; one was polymorphic; and one was the papillary type. The histograms of nuclei in the surgical specimens were compared with those obtained from primary tissue culture cells prepared from tumor samples. Five diploid meningiomas had abnormal values for their 4C peaks that were also manifested by their tissue culture cells showing either slightly decreased or increased values during a 7- to 14-day period. Strong variations of the histograms were seen in the original material and in the primary tissue culture of the polymorphic tumor and the aneuploid meningioma of the papilary type. It is suspicious that in vitro proliferating meningioma tissue may be an index for a high risk of recurrence. The results of these seven cases are in contrast to eight further meningiomas of this series with more or less "indifferent" diploid histograms, thus suggesting that there could also be a scale of proliferative potentials of the different meningiomas rapidly demonstrable by means of flow fluorescence cytometry.

[Glial fibrillary acidic protein and central nervous system tumors. Immunohistochemical study of a series of 207 cases. 2: Medulloblastomas. Hemangioblastomas. Other tumors. Discussion]. / Protéine gliofibrillaire acide (GFA) et tumeurs nerveuses centrales. Etude immunohistochimique d'une série de 207 cas. IIe Partie: Médulloblastomes. Hémangioblastomes. Autres tumeurs. Discussion.

The presence of glial fibrillary acidic protein (GFA) was tested in biopsy or autopsy specimens of 207 human central nervous system tumors. Samples were fixed, paraffin-embedded and GFA was detected using the peroxidase-antiperoxidase technique. The second part of this study dealt mainly with medulloblastomas and hemangioblastomas. Of the 17 cerebellar medulloblastomas, 15 contained less than 5% GFA positive cells. These were classified according to the Mannoji et al., 1981, criteria. Ten medulloblastomas contained type 1, 2 and 3 cells; 1 was composed of only type 1 cells, and 4 were composed of only type 3 cells. Of the 8 cerebellar or medullary hemangioblastomas, 3 contained only a few GFA positive cells which were, in two cases stroma cells and in another, astrocytes. GFA positive cells were found in 7 oligoastrocytomas, 3 gangliogliomas and 1 hamartoma of the hypothalamus. Similarly, a GFA positive astrocytic differentiation was found in a pineocytoma. In a case of tuberous sclerosis no GFA was found in the giant cells of cortical tubers. Nor was GFA observed in one intracerebral tumor of tuberous sclerosis. GFA was not found in 5 meningiomas, 4 oligodendrogliomas, 4 pituitary adenomas, 3 neurinomas of the VIII cranial nerve, 1 primary cerebellar malignant lymphoma, 1 familial lymphohistiocytosis with cerebellar involvement and 4 brain metastases. The authors also include diagnostic, histogenetic and nosological comments -about neuroglial tumors. The findings in the two parts of this study fail to establish a correlation between GFA positivity and histological grade of astrocytomas and glioblastomas.

[Kaposi's sarcoma: comparative immunohistochemical study and histogenic significance of endothelial markers]. / Sarcome de Kaposi: étude immunohistochimique comparative et intérêt histogénétique des marqueurs endothéliaux.

The origin of spindle-shaped cells in Kaposi's sarcoma (KS) remains controversial. Non-specific histochemical reactions, electron microscopic examinations and immunostainings using antibody against factor VIII-related antigen (F VIII-RAG) and Ulex europaeus agglutinin I (UEAI) lectin as endothelial markers have given contradictory results. Immunohistochemical techniques were applied to 7 frozen skin biopsy specimen of KS from 5 elderly Mediterranean people and 1 renal allograft recipient, and a group of 27 other frozen cutaneous tumours including haemangio and lymphangiosarcomas, benign vascular lesions and various epithelial, melanocytic, fibrohistiocytic, fibrosarcomatous and muscular tumours. Using UEAI and antibodies against F VIII-RAG, HLA-DR and vimentin, a large proportion of positive KS spindle cells was found in all cases whereas cells were negative for keratin. Among the various immunoreactivity patterns observed in this study, a unique immunohistochemical profile was demonstrated for KS, angiosarcoma and endothelial cell, which strongly supports the endothelial origin of spindle cells in KS. Whereas F VIII-RAG, HLA-DR, vimentin and UEAI were sensitive endothelial markers, only F VIII-RAG appeared specific for endothelial cells since UEAI stained 2 squamous cell carcinomas and HLA-DR and vimentin were present in various mesenchymal and melanocytic tumours.

[Immunohistochemical studies of hemangioblastoma with glial fibrillary acidic protein].

Sixteen cases of CNS hemangioblastoma were examined for glial fibrillary acidic protein (GFAP) using the immunoperoxidase method. In 13 cases GFAP-positive cells were found in the tumor. In all positive cases reactive gliosis in the form of trapped reactive astrocytes and their cytoplasmic processes penetrated the margin of the tumor. In 4 of the positive cases GFAP-positive cells were present deep in the tumor. Aggregates of GFAP-positive cells and fibrils were especially prominent in a recurrent case. Because hemangioblastomas grow without capsule into the cerebellar tissue, it is considered that reactive astrocytes and their fibrils are easily included and trapped within the tumor. In two cases GFAP-positive plump stromal cells, which were definitely different from the reactive astrocytes, were seen. They were neighbored with the dense gliotic foci or on and around the microcyst wall. This may be interpreted as that the stromal cells have a capacity to incorporate the extracellular GFAP derived from the intratumoral gliotic foci or cysts.

Evidence that renin substrate (angiotensinogen) may be a precursor of erythropoietin.

We suggested a role for renin substrate (RS, angiotensinogen) in the biogenesis of erythropoietin (EP) (Nature 308:649-652, 1984). Purified RS was prepared from pooled plasma of healthy adult subjects, or from plasma of pregnant, healthy females. Antisera against human RS were shown to cross-react with purified human urinary EP, using a haemagglutination technique. On the other hand, antisera generated against highly purified human urinary EP showed strong cross-reaction with purified human plasma RS, by agglutinating erythrocytes covered with glutaraldehyde-coupled human RS. Moreover, using antisera generated against RS or EP, we have demonstrated monocytoid cells staining positive for both EP and RS in cerebellar haemangioblastoma tumors from 8 patients. Taken together, these observations point to a close relation between RS and EP. One interesting explanation is that renin substrate may be a precursor of erythropoietin.

[Paratesticular angiosarcoma. Immunohistochemical confirmation. Review of the literature]. / Angiosarcoma paratesticular. Confirmación inmunohistoquímica. Revisión de la literatura.

We report a case of paratesticular angiosarcoma. To our knowledge, no well-documented case involving this site has been reported in the literature. The anatomopathological features of the present case are described, highlighting immunohistochemical analysis. The outstanding clinical features of this aggressive tumor type are discussed.

Endothelium and thrombomodulin: expression and distribution of thrombomodulin on altered endothelium and neoplastic syncytiotrophoblast.

We investigated the expression of thrombomodulin (TM) on endothelium in some pathologic states. We used the cultured endothelial cells treated with interleukin-1 (IL-1) and propagated cells by serial subculture for extended periods of time and assessed cell-surface TM molecules. We also studied the distribution of TM on surgical specimens of chorionic diseases, angiosarcoma and on several established cell lines of human choricarcinoma. Subculture of human umbilical vein endothelial cells (HUVE) up to 2 months (approximately 16 subcultures) decreased the number of cell-surface TM molecules by approximately 20% compared to the primary culture. The number of TM molecules also decreased on HUVE treated by IL-1. The treatment of the cells with IL-1 also induced change of shape. TM was found not only normal syncytiotrophoblast but also on neoplastic syncytiotrophoblast of choriocarcinoma and hydatidiform mole. However, TM was not expressed on the three established cell lines. TM was found on various types of vascular tumors, including angiosarcoma.

Erythropoietin levels in posterior fossa haemangioblastoma.

Using an in vitro bioassay, erythropoiesis stimulating activity has been measured in serum, cyst fluids and tumour homogenates from fourteen patients with cerebellar haemangioblastoma. Only two patients had elevated peripheral blood red cell counts and haemoglobin concentrations. Significantly elevated serum erythropoiesis stimulating activity was found in only one patient. High level, however, were detected in seven out of the fourteen cyst fluids and in the two homogenates tested. The dose response lines from these paralleled those of normal human erythropoietin. It was possible to neutralise the erythropoiesis stimulating activity in the cyst fluids with anti-human erythropoietin serum, indicating its similarity to erythropoietin, the normal erythropoietic regulating hormone. Significant release of the erythropoietic stimulating factor from the cyst fluids into the blood seemed to be an uncommon occurrence.

Steroid hormone and epidermal growth factor receptors in meningiomas.

A prospective study of steroid hormone and epidermal growth factor receptor expression in 57 meningiomas is presented. Scatchard analysis of radioligand binding identified 20% of meningiomas as expressing classical oestrogen receptors (ER) at levels below that normally accepted for positivity, the remainder being negative. ER could not be visualized in any meningioma using immunocytochemistry. Alternatively, 74% of meningiomas demonstrated the presence of progesterone receptors (PR) by Scatchard analysis, the specificity of which could not be attributed to glucocorticoid or androgen receptors. Confirmation of classical PR presence was determined by immunocytochemical staining. The presence of epidermal growth factor receptor (EGFR) was demonstrated in 100% of meningiomas using immunocytochemical staining. These data are reviewed in the context of previously reported results and are discussed in relation to the potential for medical therapy as an adjunct to surgery.