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Case Reports

Abstract

Verrucous venous malformation (VVM), previously termed verrucous hemangioma, is an uncommon congenital vascular anomaly with a somatic missense mutation in MAP3K3. Clinically, it can present as a violaceous, wart-like plaque. Histologically, VVM demonstrates crusted papillomatosis overlying numerous dilated and congested capillaries and venules in the papillary dermis, mimicking angiokeratoma. In excisional/deep sampling, careful inspection reveals numerous congested capillaries involving the reticular dermis and subcutaneous tissue. This deeper component is usually diagnostic; however, it can also resemble an infantile hemangioma (IH). 

We report two patients diagnosed with VVM: a 21-year-old female who presented to the dermatology clinic with a sizable and complex violaceous plaque on her lower back since birth; and a 15-year-old male who presented to the orthopedic department for the removal of a “ganglion cyst”. Both lesions showed nearly identical histopathology of numerous dilated and congested capillaries and venules in the papillary and reticular dermis, as well as in the subcutaneous adipose tissue. Recognizing these features was diagnostic for VVM; however, GLUT1 immunohistochemistry (IHC) was performed to exclude IH. Only focal GLUT1 endothelial expression was detected in both lesions, confirming the diagnosis. IHC for CD31 and ERG helped better define the extent of the lesions. Podoplanin (D2-40, lymphatic marker) was negative, and WT-1 incompletely highlighted the endothelial cell membrane.

We aim to highlight the histopathology and IHC work-up to clench the diagnosis of VVM; and reemphasize the need for a deep punch/excisional biopsy in a suspected VVM case to avoid the diagnostic pitfall of angiokeratoma.