Background
Benign lymphangioendothelioma (BLAE) (also known as acquired progressive lymphangioma) is an uncommon vascular tumor that is of importance primarily because it can be confused histologically with Kaposi sarcoma (KS) or angiosarcoma. [1, 2] Jones et al first described the tumor as acquired progressive lymphangioma and later as benign lymphangioendothelioma. [3]
Pathophysiology
Benign lymphangioendothelioma is a proliferation of lymphatic endothelial cells that stain positively for CD31, CD34, podoplanin (D2-40, a lymphatic marker), LYVE-1, and PORX-1. [4, 5] Benign lymphangioendothelioma is not associated with preexisting vascular malformations or lymphedema. Although the lesion rarely is identified during infancy, some suggest it is a hamartoma that first becomes apparent during adolescence or young adult life; the development of benign lymphangioendothelioma is possibly triggered by hormonal changes.
Etiology
In most instances, the cause is unknown. Trauma has often been blamed, [6] but a reliable connection has never been established. A reactive process versus tumoral etiology is suggested in some literature. [7] In one patient, femoral arteriography was proposed to be a trigger. [8] One case has been reported in association with HIV/AIDS. [9]
Epidemiology
US frequency
Benign lymphangioendothelioma is rare; fewer than 30 cases have been reported.
Race
No racial predisposition is reported.
Sex
Males and females are affected equally.
Age
Benign lymphangioendothelioma can affect patients ranging from age 17-90 years (median age 54 y). [1]
Prognosis
The prognosis is excellent.
Patient Education
Inform patients they have a rare (though benign) vascular tumor that is poorly understood, and annual screening is recommended.
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Erythematous nodule with macular component at the periphery.
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Overview of a histologic section from a tumor depicting dilated vascular spaces interspersed between collagen fibers and a more central accumulation of many complex vascular spaces.
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High-power view showing dilated vascular channel with innocent endothelial cells.
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High-power view showing lymphatic endothelial cells in a hematoxylin and eosin–stained section.
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High-power view showing lymphatic endothelial cells stained positively with podoplanin.