Quick Review for Patients
Note: click on underlined words for more detail or photos.
A varied group of proliferative and neoplastic vascular lesions, called
collectively hemangioendothelioma, seems to have a biological behavior
which falls somewhere between the benign hemangioma and malignant
10% of cases are associated with other developmental anomalies or syndromes,
including early onset varicose veins, lymphedema,
Klippel-Trenaunay-Weber syndrome, and Maffucci's
Most cases present as red/blue nodules which may be multiple and are usually quite
superficial. Diagnosis is typically made during the second
and third decades of life and there is no gender predilection.
Pathology and Differential Diagnosis
The hemangioendothelioma is a poorly circumscribed, usually biphasic proliferation of venous or capillary vessels. There are dilated and congested veins with inactive endothelial cell nuclei and with occasional thrombi or phleboliths. These vessels are intermixed with solid sheets of epithelioid (epithelioid hemangioendothelioma) or spindle-shaped (spindle cell hemangioendothelioma) mesenchymal cells with minimal dysplasia, few mitotic figures, and minimal differentiation toward a vascular lumen or channel.
Slit-like vascular channels, similar to those of Kaposi's sarcoma, are often seen, perhaps with mild extravasation of erythrocytes and hemosiderin deposition within or outside of macrophages. It should be mentioned that the Kaposiform hemangioendothelioma, with its histopathologic admixture of tissues similar to both capillary hemangioma and Kaposi's sarcoma, has not yet been reported from an oral or pharyngeal location.
The clustering or grouping of the endothelial cells of this tumor is more readily apparent with the use of reticulin staining, which shows fibers surrounding solid clusters with or without a small central vascular lumen ("microlumen"). Thick-walled vascular channels may be seen at the lesional periphery, and the tumor frequently demonstrates areas of necrosis or dense fibrosis.
The epithelioid cells have abundant eosinophilic cytoplasm, may contain vacuoles (primitive lumina), and may be admixed with smooth muscle bundles. These cells stain positively with Ulex europaeus and many will show cytoplasmic factor VIII-associated antigen reactivity with immunohistochemistry. Tumor cells also stain for endothelial markers such as CD31 and CD34 in approximately one-fifth of cases.289 Some epithelioid hemangioendotheliomas have a myxoid or hyaline stroma, and aldehyde fuchsin (pH 1.0) staining may reveal sulfated acid mucopolysaccharides in this stroma.
The lesional cells of the spindle cell hemangioendothelioma are rather bland, bipolar mesenchymal fibroblast-like cells which may contain vacuoles, presumed to be abortive or primitive vascular lumina. Epithelioid cells are usually seen in small numbers in scattered areas and the associated dilated venous channels are more prone to contain thrombi and phleboliths than are those of the epithelioid hemangioendothelioma. Factor VIII-associated antigen is often found within the endothelium of the venous channels, but the spindle cells are typically negative.
The pathologist must be careful to rule out metastatic carcinoma
or melanoma, which typically display much more dysplasia than
hemangioendothelioma. The various epithelioid sarcomas must also
be ruled out, especially the epithelioid angiosarcoma. These are
discussed elsewhere in the present section.
Treatment and Prognosis
Hemangioendothelioma is treated with wide surgical excision, with more than half of all cases recurring at the operative site or several centimeters distant. Those tumors with significant cellular atypia and mitotic activity are associated with more aggressive clinical behavior, but not all tumors which metastasize have these changes at initial biopsy.
Almost a third of epithelioid hemangioendotheliomas develop metastases in
regional lymph nodes (at least 50%+ of all metastatic cases) or in the lungs,
liver or bones. Patients who develop metastases have a 50%
five-year survival rate. The spindle cell hemangioendothelioma is rarely
associated with metastasis but has a higher rate of local recurrence than
does the epithelioid variant of this tumor, 60% vs. 13%,
References (Chronologic Order)
Note: General references can be found by clicking on that topic to the left.
Ellis GL, Kratochvil FJ. Epithelioid hemangioendothelioma of the head and neck: a clinicopathologic report of twelve cases. Oral Surg Oral Med Oral Pathol 1986; 61:61-68.
Weiss SW, Ishak KG, Dail DH, et al. Epithelioid hemangioendothelioma and related lesions. Semin Diagn Pathol 1986; 3:259-287.
Scott GA, Rosai J. Spindle cell hemangioendothelioma: report of seven additional cases of a recently described entity vascular neoplasm. Am J Dermatopathol 1988; 10:281-288.
Lai FM, Allen PW, Yuen PM, et al. Locally metastasizing vascular tumor: spindle cell, epithelioid, or unclassified hemangioendothelioma. Am J Clin Pathol 1991; 96:660-663.
Zukerberg LR, Nickoloff BJ, Weiss SW. Kaposiform hemangioendothelioma of infancy and childhood: an aggressive neoplasm associated with Kasabach-Merritt syndrome and lymphangiomatosis. Am J Surg Pathol 1993; 17:321-328.
Fukunaga M, Ushigome S, Ishikawa E. Kaposiform hemangioendothelioma associated with Kasabach-Merritt syndrome. Histopathol 1996; 28:281-284.
Polk P, Webb JM. Isolated cutaneous epithelioid
hemangioendothelioma. J Amer Acad Dermatol 1997; 36:1026-1028.
Note: To see enlarged photo, click on
the left-hand picture;
|Figure 5: [return to text]|
|Figure 6: [return to text]|
|Figure 7: [return to text]|
|Figure 8: [return to text]|