Extracutaneous angiosarcomas metastatic to the lungs: clinical and pathologic features of twenty-one cases

Angiosarcomas are rare malignant vascular tumors with a high rate of metastasis involving lungs (most commonly), liver, regional lymph nodes, bone, and other sites. In this study, we have reviewed the clinical presentation and histopathology of 21 cases of extracutaneous angiosarcoma metastatic to the lungs. Tumors with exclusively pleural involvement were excluded. Patients presented with dyspnea, chest pain, and/or hemoptysis lasting a few weeks to months. Radiologically, the most common finding comprised multiple peripheral lung nodules (57%), often accompanied by infiltrates. For 11 cases (52%), the primary tumor was not identified at the time of presentation. Vasoformative areas were identified in 15 cases (71%). Nine cases comprised spindle cells (43%), two contained epithelioid cells (9.5%), and 10 consisted of both spindle and epithelioid cells (48%). Nuclear pleomorphism was at least moderate in all cases. However, five tumors contained regions of minimal nuclear atypia. Hemorrhage, siderophages, and fibrosis were commonly present. Immunohistochemical staining (IHS) was performed on 14 cases. Thirteen tumors showed reactivity for vascular markers. Tumor cells reacted for Von Willebrand factor in 13 of 14 cases, and CD31 and CD34 were each positive in 2/2 cases. Two cases (of nine examined) also expressed cytokeratins. Because the tumor often first presented in the lungs before the primary sarcoma was identified, the clinical impression included both benign and malignant entities. For patients with primary cardiac tumors, symptoms referable to the primary tumor complicated the clinical presentation, and radiologic evaluation supported a clinical diagnostic impression of non-neoplastic pericarditis. Thus, angiosarcoma in the lung may elude diagnosis until histopathologic evaluation of the lung biopsy.