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Primary polymorphous hemangioendothelioma of the maxillary soft tissue: clinical and immunopathological aspects of a rare vascular neoplasm.

Polymorphous hemangioendothelioma (PH) is an uncommon vascular neoplasm of borderline malignant potential characterized by a considerable variability in patterns of cellular growth. Morphologically, PH may be confused with other lesions, from benign vasoformative neoplasms and reactive inflammatory conditions to malignancies such as angiosarcoma or squamous cell carcinoma. Most occur in the lymph nodes, and to the best of our knowledge, lesions involving the maxillary soft tissue have not been described in the literature to date. A potential for local recurrence, as well as the ability to metastasize, has been for this type of neoplasm. Here we reported on a rare case of polymorphous hemangioendothelioma which presented as an asymptomatic subcutaneous mass in the right zygomatic region of a 22-year-old white female. We discuss the histopathological aspects of this tumor, with emphasis on the role of immunohistochemical analysis in differential diagnosis.