An authentic malignant epithelioid hemangioendothelioma of the thyroid: a case report and review of the literature.

Hemangioendotheliomas of the thyroid are neoplasms that are rarely encountered in the Alpine region in Europe. The endemic goiter in this iodine-deficient region can be considered as a predisposing factor. We report the second case of an epithelioid hemangioendothelioma (EHE) of the thyroid gland and the first clinical case with malignant behavior. A 73-year-old woman with a long history of multinodular goiter presented with a rapidly growing thyroid mass, free of distant metastases. A total thyroidectomy was performed. Histologically the lesion had characteristic epithelioid and spindle cell proliferation in a background of chondromyxoid stroma. Cytoplasmic vacuolization in the epithelioid and spindle cells were present. Tumor cells were positive for factor VIII-related antigen, MNF116, PAN-ceratin, CD 34, and CD 31 and negative for cytokeratin allowing the diagnosis of EHE. Nine months after the primary resection the tumor locally recurred. A palliative resection was performed in a second operation followed by interferon-alpha therapy. The patient rapidly developed a second local relapse and died 13 months after the diagnosis of an EHE had been made. An improvement of the very poor prognosis of this rare tumor may depend on early tumor diagnosis and surgery combined with a multimodal treatment.