Verrucous hemangioma revisited.

We analyzed the clinical and histopathologic characteristics of verrucous hemangioma, compared these findings to hyperkeratotic mimickers such as capillary-lymphatic malformation or capillary-venous malformation and angiokeratoma circumscriptum, and reconsidered whether the term verrucous hemangioma is appropriate in the current nosology of vascular anomalies. Fourteen similar-appearing localized hyperkeratotic vascular lesions were identified by one surgeon as either angiokeratoma, angiokeratoma circumscriptum, capillary-venous malformation, capillary-lymphatic malformation, or verrucous hemangioma. All lesions were located on an extremity, except for one lesion on the trunk, and were single or grouped and 2.6 to 8 cm in diameter. All were raised, red-to-purple, variably keratotic with irregular borders, and several manifested intermittent bleeding and oozing. Excision was performed at 4 months to 16 years of age. After histologic review, three lesions were designated as combined vascular malformations composed of capillaries, lymphatics, and veins, and none was designated as angiokeratoma. Eleven of 14 specimens met the histologic criteria for verrucous hemangioma: a hyperkeratotic epidermis with small, thick-walled, blood-filled vessels with multilamellated basement membrane involving the entire dermis as well as the subcutis. Immunostaining showed focal GLUT1 endothelial positivity (7/11) and low-level MIB-1 reactivity (8/11). Verrucous hemangioma has the accepted clinical features of vascular malformation, specifically presence at birth and proportionate growth. Microscopic features, such as thick vascular walls, multilamellated basement membrane, relatively uniform channel size, and GLUT1 immunopositivity are reminiscent of infantile hemangioma, particularly in its involutive phase. No firm conclusion seems possible as to whether verrucous hemangioma is a malformation or an indolent tumor, but clinical evidence favors the former category.