Angiosarcomas express mixed endothelial phenotypes of blood and lymphatic capillaries: podoplanin as a specific marker for lymphatic endothelium. (1/508)

Angiosarcomas apparently derive from blood vessel endothelial cells; however, occasionally their histological features suggest mixed origin from blood and lymphatic endothelia. In the absence of specific positive markers for lymphatic endothelia the precise distinction between these components has not been possible. Here we provide evidence by light and electron microscopic immunohistochemistry that podoplanin, a approximately 38-kd membrane glycoprotein of podocytes, is specifically expressed in the endothelium of lymphatic capillaries, but not in the blood vasculature. In normal skin and kidney, podoplanin colocalized with vascular endothelial growth factor receptor-3, the only other lymphatic marker presently available. Complementary immunostaining of blood vessels was obtained with established endothelial markers (CD31, CD34, factor VIII-related antigen, and Ulex europaeus I lectin) as well as podocalyxin, another podocytic protein that is also localized in endothelia of blood vessels. Podoplanin specifically immunolabeled endothelia of benign tumorous lesions of undisputed lymphatic origin (lymphangiomas, hygromas) and was detected there as a 38-kd protein by immunoblotting. As paradigms of malignant vascular tumors, poorly differentiated (G3) common angiosarcomas (n = 8), epitheloid angiosarcomas (n = 3), and intestinal Kaposi's sarcomas (n = 5) were examined for their podoplanin content in relation to conventional endothelial markers. The relative number of tumor cells expressing podoplanin was estimated and, although the number of cases in this preliminary study was limited to 16, an apparent spectrum of podoplanin expression emerged that can be divided into a low-expression group in which 0-10% of tumor cells contained podoplanin, a moderate-expression group with 30-60% and a high-expression group with 70-100%. Ten of eleven angiosarcomas and all Kaposi's sarcomas showed mixed expression of both lymphatic and blood vascular endothelial phenotypes. By double labeling, most podoplanin-positive tumor cells coexpressed endothelial markers of blood vessels, whereas few tumor cells were positive for individual markers only. From these results we conclude that (1) podoplanin is a selective marker of lymphatic endothelium; (2) G3 angiosarcomas display a quantitative spectrum of podoplanin-expressing tumor cells; (3) in most angiosarcomas, a varying subset of tumor cells coexpresses podoplanin and endothelial markers of blood vessels; and (4) all endothelial cells of Kaposi's sarcomas expressed the lymphatic marker podoplanin.  (+info)

Vaginal epithelioid angiosarcoma. (2/508)

A case of epithelioid angiosarcoma of the vagina is described. Only five cases of angiosarcoma at this site have been reported, three of which followed radiotherapy for other gynaecological malignancies. None is described as an epithelioid angiosarcoma, an unusual and recently described variant which is readily confused with carcinoma. This is thought to be the first reported epithelioid angiosarcoma at this site and highlights the difficulties in diagnosis.  (+info)

Primary right atrial angiosarcoma mimicking acute pericarditis, pulmonary embolism, and tricuspid stenosis. (3/508)

A 29 year old white man presented to the emergency room with new onset pleuritic chest pain and shortness of breath. He was initially diagnosed as having viral pericarditis and was treated with non-steroidal anti-inflammatory drugs. A few weeks later he developed recurrent chest pain with cough and haemoptysis. Chest radiography, cardiac examination, transthoracic and transoesophageal echocardiography pointed to a mass that arose from the posterior wall of the right atrium, not attached to the interatrial septum, which protruded into the lumen of the right atrium causing intermittent obstruction of inflow across the tricuspid valve. Contrast computed tomography of the chest showed a right atrial mass extending to the anterior chest wall. The lung fields were studded with numerous pulmonary nodules suggestive of metastases. A fine needle aspiration of the pulmonary nodule revealed histopathology consistent with spindle cell sarcoma thought to originate in the right atrium. Immunohistochemical stains confirmed that this was an angiosarcoma. There was no evidence of extracardiac origin of the tumour. The patient was treated with chemotherapy and radiation. This case highlights the clinical presentation, rapid and aggressive course of cardiac angiosarcomas, and the diagnostic modalities available for accurate diagnosis.  (+info)

Primary cardiac Kaposi's sarcoma. (4/508)

We report the clinical, laboratory, and necropsy findings in a 14-year-old boy with a primary Kaposi's sarcoma of the heart. Primary cardiac Kaposi's sarcoma and angiosarcoma are compared, and the pathogenesis of Kaposi's sarcoma is discussed. Relevant literature is briefly reviewed.  (+info)

Biological effects of vinyl chloride: an experimental study. (5/508)

Plasma activities of alkaline phosphatase, (AP), transaminases and total lactate dehydrogenase (LDH) with isoenzymes were determined in mice inhaling 50 and 550 ppm vinyl chloride (VC). The animals were also autopsied and the tissue pathology was studies. The total LDH activity was elevanted in both dose groups along with a shift to cathodic enzymes. AP was increased in animals exposed to 500 ppm and transaminases were not at all changed. Enzyme changes occurred after the appearance of tumors. Alveologenic adenomas occurred in all animals at the higher dosage and in about half of the animals inhaling the lower dose. Subperitoneal and subcutaneous hemangiosarcomas were frequent in both dose groups; but especially among 50 ppm animals. Only one animal had a hemangiosarcoma of the liver. No liver fibrosis was seen. All primary subperitoneal and subcutaneous tumors were located in fat tissue. Telangiectasis was observed in two animals in the 500 ppm series. The importance of blood vessel changes in the toxicology of vinyl chloride is discussed.  (+info)

Case report: spontaneous hemangiosarcoma in the pancreas of a Fischer rat. (6/508)

Spontaneous hemangioma or hemangiosarcoma is sometimes found in the viscera and soft tissue of rats and mice. However, there is no report of the tumor occurring in the pancreas of rats. We report a pancreatic hemangiosarcoma in a 109-wk-old, male Fischer 344 rat, which was used in the control group of a carcinogenicity study. The tumor destroyed and compressed the normal pancreatic tissue and displayed a high density in terms of the numerous capillaries and strands of endothelial tumor cells. A reticulin stain revealed a dense network formation. The frequency of proliferating cell nuclear antigen-positive staining showed active proliferation of the tumor cells. Immunohistochemically, some of the tumor cells stained positive with factor VIII-related antigen, and ultrastructurally, Weibel-Palade bodies were rarely observed in the cytoplasm of the tumor cell. From these findings, the tumor was diagnosed as a hemangiosarcoma that occurred naturally in the pancreas.  (+info)

The risk of angiosarcoma following primary breast cancer. (7/508)

Lymphangiosarcoma of the upper extremity is a rare and aggressive tumour reported to occur following post-mastectomy lymphoedema (Stewart-Treves syndrome). Haemangiosarcoma, a related rare tumour, has occasionally been reported to occur in the breast following irradiation. We conducted a case-control study using the University of Southern California-Cancer Surveillance Program, the population-based cancer registry for Los Angeles County, to evaluate the relationship between invasive female breast cancer and subsequent upper extremity or chest lymphangiosarcoma and haemangiosarcoma together referred to as angiosarcoma. Cases were females diagnosed between 1972 and 1995 with angiosarcoma of the upper extremity (n = 20) or chest (n = 48) who were 25 years of age or older and residing in Los Angeles County when diagnosed. Other sarcomas at the same anatomic sites were also studied. Controls were females diagnosed with cancers other than sarcoma during the same time period (n = 266,444). Cases and controls were then compared with respect to history of a prior invasive epithelial breast cancer. A history of breast cancer increased the risk of upper extremity angiosarcoma by more than 59-fold (odds ratio [OR] = 59.3, 95% confidence interval [95% CI] = 21.9-152.8). A strong increase in risk after breast cancer was also observed for angiosarcoma of the chest and breast (OR = 11.6, 95% CI = 4.3-26.1) and for other sarcomas of the chest and breast (OR = 3.3, 95% CI = 1.1-1.7).  (+info)

Primary cardiac angiosarcoma associated with cardiac tamponade: case report. (8/508)

A 57-year-old male with primary cardiac angiosarcoma was initially admitted for cardiac tamponade. Pericardiocentesis was performed twice preoperatively, but the bloody pericardial fluid was cytologically negative for malignant cells. The tumor in the right atrium was resected during cardiopulmonary bypass. The resected tumor was 5.5x4.5x3.0cm in size and the diagnosis of cardiac angiosarcoma was made histologically. There were no tumor cells in the surgical margin. Unfortunately the patient died 3.5 months after surgery due to multiple recurrence in the pericardium. A suitable therapy for cardiac angiosarcoma is still controversial, but early antemortem diagnosis and more aggressive combined treatment should be considered.  (+info)