Epithelioid hemangioendothelioma of the head and neck: role of podoplanin in the differential diagnosis.

Epithelioid hemangioendothelioma is an uncommon vascular tumor of soft tissue and bone that may rarely occur in the liver, lung and the head and neck. We present five new cases of epithelioid hemangioendothelioma of the head and neck region diagnosed and managed in one institution in order to define the phenotypic characteristics, podoplanin immunohistochemical staining and the biological outcome. Podoplanin is a transmembrane mucoprotein selectively expressed in lymphatic endothelium and recently in some vascular neoplasms. The patients were comprised of two male and three female patients ranging in age from 4 to 71 years. The lesions were found in the gingiva, submandibular region soft tissue, nasal cavity and tongue, and ranged in size from 0.7 to 2.5 cm. All tumors manifested infiltrative cords and nests of epithelioid cells with occasional spindle morphology in a myxoid stroma. Immunohistochemical analysis of vascular and epithelial markers showed strong and uniform cytoplasmic reactivity for podoplanin and variable intensity and staining of CD31 and lack of cytokeratin staining in tumor cells. Surgical treatment included simple and wide local excisions. Of the three patients with follow-up, one developed lymph node metastasis and one had no evidence of disease 10 months after surgery. The patient with multiple recurrences and LN metastases was additionally treated with chemotherapy and is under consideration for radiation therapy. Hemangioendothelioma of the head and neck is: (1) a low-grade malignancy with a tendency for local recurrence and regional lymph node metastasis, (2) complete excision with negative margins is the treatment of choice for localized disease and (3) podoplanin may be useful in differentiating epithelioid hemangioendothelioma from non-vascular tumors.