Nodal and extranodal soft tissue polymorphous hemangioendothelioma: a case report and review of the literature.

BACKGROUND Polymorphous hemangioendothelioma is a rare vascular tumor of borderline malignant potential and only 10 cases have been described in the literature so far. METHODS AND RESULTS We report a case of nodal and extranodal polymorphous hemangioendothelioma and review the literature. A 66-year-old man with an unremarkable past medical history was admitted for a left submandibular mass. The main nodule was composed of angiosarcoma-like areas mixed with angiomatous features; some vascular spaces with hobnail endothelium were seen. The tumor involved two adjacent lymph nodes. Immunohistochemically, the neoplastic cells were strongly positive for CD31 and vimentin. After a few months the tumor recurred and the patient was treated with radiation therapy. CONCLUSIONS Polymorphous hemangioendothelioma is a distinct entity in the hemangioendothelioma group with its own clinical and histological features.