[Persistent hemoptysis secondary to extensive epithelioid angiosarcoma].
Pulmonary angiosarcoma is an unusual cause of diffuse pulmonary hemorrhage. Angiosarcomas are rare malignant vascular tumors accounting for 1% to 2% of all sarcomas. Angiosarcomas have been detected in nearly all organs, but lung involvement is unusual, accounting for less than 7%. The literature describes approximately 10 isolated cases of primary pulmonary angiosarcoma as opposed to the more common metastatic type. Given that primary and metastatic types are clinicopathologically similar, the presence of a distant primary sarcoma must be ruled out before a diagnosis of primary pulmonary angiosarcoma can be made. A pathological diagnosis requires a finding of polygonal or oval cells with atypical irregular nuclei and vascular spaces lined with such cells surrounded by hemorrhagic phenomena. Immunohistochemical analysis is positive for specific endothelial cell markers such as CD31 and factor VIII, and coexpression of keratin is a frequent finding.