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Neuroradiology Case of the Week

Case 339

August 2008

Harshabad Singh,MBBS and Per-Lennart Westesson, MD, PhD, DDS

Clinical Presentation: Patient is a 43-year-old woman with history of metastatic epithelioid hemangioendotheliomas treated with radiation treatment in the past, with extensive axial and appendicular skeletal involvement, now with slurred speech and deviation of the tongue, presented for further evaluation.

Imaging Findings: Magnetic resonance imaging (MRI) is nowadays the most useful examination to establish the diagnosis of calvarial metastasis, but plain films, CT scans with bone windows and isotope bone scans remain helpful to demonstrate bone erosions. Normal imaging studies do not exclude the diagnosis.

Diagnosis: Metastatic epithelioid hemangioendothelioma

Discussion: Hemangioendothelioma is an uncommon vascular tumor with biologic behavior intermediate between hemangiomas and angiosarcomas.The epithelioid variant has the most aggressive course [1]. The principal locations are liver, lung and bones, where they tend to be multifocal [2]. Epithelioid hemangioendotheliomas have been reported to occur in infants as well as in the aged; the male-to-female ratio varies with the tumor location. It is a borderline or low grade malignant tumor. Recurrences are common and metastasis occurs in up to 31% of cases [3]. Both primary and metastatic intracerebral epithelioid hemangioendotheliomas are extremely rare.
     The histology is characterized by epithelioid endothelial cells that grow in  cords and nests in a myxoid stroma. There are intracytoplasmic vacuoles which may contain erythrocytes but well defined vessels are absent. Immunohistochemical evidence of endothelial differentiation in the form of positivity for factor VIII-related antigen, CD 31,34 is an important criteria for the diagnosis. This tumor is positive for mesenchymal marker vementin and negative for epithelial markers. About one forth of these tumors may show atypia but the histologic grading system is not useful for predicting prognosis [2,4].
     In our patient brain imaging for her new onset focal neurological symptoms showed multiple calvarial lesions. Calvarial metastasis can be caused by nearly all types of tumors but breast cancer is associated with highest rate of metastatic skull lesions. Lung and prostate are other common malignancies which metastasize to the skull. Most metastatic skull lesions are asymptomatic, although they can cause symptoms due compression of dural sinuses and cranial nerves. In case of solitary lesion, the metastasis need to be differentiated from primary skull tumors like osteoma, chondroma, chondrosarcoma, chordomadermoid, epidermoid, etc. and tumor-like lesions like fibrous dysplasia, hyperostosis, eosinophilic granuloma, etc. Patients with skull metastases are characterized by higher age and shorter duration of symptoms as compared from those with primary bone lesions [5].
     The treatment for calvarial metastasis depends on the nature of the underlying tumor. Radiotherapy is generally the standard treatment, while some patients with chemosensitive or hormonosensitive lesions benefit from chemotherapy or hormonotherapy and selected patients from surgical removal [6].

References:

1. Gokhan GA, Akyuz M, Gurer IE, Tuncer R. Epithelioid hemangioendothelioma derived from the spine region: case report and review of the literature. Wien Klin Wochenschr. 2006 Jun;118(11-12):358-61. [Medline]
   
2. Pigadas N, Mohamid W, McDermott P. Epithelioid hemangioendothelioma of the parotid salivary gland. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2000 Jun;89(6):730-8. [Medline]
   
3. Weiss SW, Ishak KG, Dail DH, Sweet DE, Enzinger FM. Epithelioid hemangioendothelioma and related lesions. Semin Diagn Pathol. 1986 Nov;3(4):259-87. [Medline]
   
4. Evans HL, Raymond AK, Ayala AG. Vascular tumors of bone: A study of 17 cases other than ordinary hemangioma, with an evaluation of the relationship of hemangioendothelioma of bone to epithelioid hemangioma, epithelioid hemangioendothelioma, and high-grade angiosarcoma. Hum Pathol. 2003 Jul;34(7):680-9. [Medline]
5. Stark AM, Eichmann T, Mehdorn HM. Skull metastases: clinical features, differential diagnosis, and review of the literature. Surg Neurol. 2003 Sep;60(3):219-25. [Medline]
6. Laigle-Donadey F, Taillibert S, Martin-Duverneuil N, Hildebrand J, Delattre JY. Skull-base metastases. J Neurooncol. 2005 Oct;75(1):63-9. [Medline]