Benign lymphangioendothelioma presenting as a giant flank mass

Abstract

Benign lymphangioendothelioma is a rare lesion of controversial etiology and a histopathologic mimic of Kaposi sarcoma and so-called 'well-differentiated' angiosarcoma. Its most typical clinical presentation is as a slowly expanding, erythematous patch or plaque; it rarely presents as a large mass. We report the second case of a giant benign lymphangioendothelioma, which arose as a serpiginous mass involving most of the flank of an elderly male with no prior radiation exposure and with a remote history of herpes zoster infection. A biopsy revealed numerous anastomosing vascular channels extending from the superficial dermis to the subcutis that were dilated to progressively slit-like in architecture. The endothelial cells lacked cytologic atypia, hobnailing, or significant mitotic activity, and human herpesvirus-8 expression was absent. Positivity for podoplanin (D2-40) was observed in the endothelial cells, supporting a lymphatic phenotype. Furthermore, the lesional cells lacked immunohistochemical expression of Wilms tumor 1, providing further support of a malformative - rather than neoplastic - pathogenesis.

Giant benign lymphangioendothelioma with positive expression of Wilms tumor 1: A case report

“…Several studies described expression for podoplanin in the endothelial cells, supporting a lymphatic differentiation. 1,2,6 In our case, podoplanin and CD31 were expressed, corroborating the lymphatic nature of the lesion.…”

“…Based on several studies suggesting that WT1 expression is seen in lesions with proliferative capacity and is not expressed in fixed lesions of malformative origin, 6 studies were unable to confirm this result. 2,3 Since the number of cases where WT1 staining was performed is still scarce, we believe that our result, even if not in accordance with the latest evidence, cannot be dismissed.…”

“…On the other hand, Kaposi sarcoma demonstrates a prominent lymphoplasmacytic infiltrate and a spindle cell component and is ultimately defined by its nuclear expression of human herpesvirus-8 (HHV-8). 2 In our case, HHV-8 staining was not performed, but the clinical and histopathologic features rule out Kaposi sarcoma.…”

“…6 All evidence points toward its running a benign course. [1][2][3][4][5][6][7] Since growth can be expected, complete surgical excision is the treatment of choice, with recurrence being reported only in the context of an incomplete excision. 4 Recently, some authors suggested that sirolimus, by acting on the phosphatidylinositol-3-kinase/protein kinase B/mechanistic target of rapamycin pathway, which is essential for cell growth and regulation of vascular maturation, may be beneficial for treating BL.…”

“…1 Typically, it affects young adolescents but may arise in adulthood, with no sex predilection. 2 It presents as an asymptomatic macule or plaque of red or bruise-like coloration, with possible superimposed papules. Histopathologically, it is characterized by thin-walled endothelial-lined spaces that are interspersed between strands of collagen.…”