malignant hemangioendothelioma

angiosarcoma

An uncommon, aggressive mesenchymal malignancy, arising in the skin, liver, breast, soft tissues and viscera, primarily affecting the elderly; male:female, 2:1.Aetiology Most are idiopathic; some are linked to chronic lymphoedema (as occurs following axillary dissection for breast CA), others to radiation therapy; hepatic angiosarcoma is classically linked exposure to thorium dioxide (a long obsolete contrast medium), and is also associated with arsenic and vinyl chloride. 
Prognosis Poor, 10–20% 5-year survival.

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