Verrucous hemangioma: a clinicopathological and immunohistochemical analysis of 74 cases.

BACKGROUND: Verrucous hemangioma is a rare form of vascular malformation. Previous studies have reported positive expression of Wilms tumor 1 (WT-1) and Glut-1 and negative expression of lymphatic markers such as D2-40 and Prox1 in verrucous hemangioma cases. However, the sample sizes of these studies were usually small.

METHODS: We analyzed 74 cases of verrucous hemangioma diagnosed in a single dermatology department and performed immunohistochemical analysis of vascular and lymphatic markers in all cases.

RESULTS: Verrucous hemangioma was usually located on the extremities. Most lesions presented as solitary or multiple hyperkeratotic plaques or nodules with various diameters. Histopathologically, the lesions showed proliferation of small- to medium-sized vessels from the papillary dermis to subcutaneous tissue. The density of the proliferated vessels varied between cases. The vessels were positive for CD31 in 74 cases, focally positive for Prox1 in 63 cases, focally positive for D2-40 in 10 cases, negative for lymphatic vessel endothelial hyaluronan receptor-1 in 74 cases, negative for WT-1 in 60 cases, and positive for Glut-1 in 49 cases.

CONCLUSION: Verrucous hemangioma is a vascular malformation with an incomplete lymphatic immunophenotype, as indicated by positive staining for Prox1 and negative staining for WT-1 in the majority of instances.