2011 Volume 9 Issue 3 Pages 241-251
Capillary hemangioma, pyogenic granuloma and cavernous hemangioma, benign vascular lesions affect in the oral regions. There have been some studies of them, but their pathological status is still controversial. The aim of the present study was to reveal the characteristic histopathological and immunohistochemical features such as cell proliferation activity, vascular proliferation factors and mesenchymal marker of these lesions in order to understand the pathological status of them. In histopathological findings of the present study, capillary hemangioma consisted of proliferating capillaries having endothelial cells and ovoid or spindle cells and associated with mast cells and lobular structures circumscribed with PAS-positive matrices. Pyogenic granuloma exhibited proliferation of the capillaries having endothelial cells and a few perivascular mesenchymal ovoid or spindle cells beneath erosive and ulcerative lesions and inflammatory changes. Cavernous hemangioma was composed of remarkably dilated and hyperplasic blood vessels. Immunohistochemically, Ki-67 labeling index of capillary hemangioma and pyogenic granuloma was higher than that of cavernous hemangioma. Positive immunoreactivity for CD34, CD105 and Tie2 was observed in some perivascular ovoid cells supported to be endothelial precursor cells. Capillary hemangioma exhibited that positive immunoreactivity for VEGF was found in the perivascular cells, mast cells and/or macrophage, whereas pyogenic granuloma showed that the positive reactivity was also seen mainly in the endothelial cells. Positive immunoreactivity for α-smooth muscle actin was identical to perivascular spindle cells, and was supposed to be pericytes. Conclusively, the present study indicated that capillary hemangioma and pyogenic granuloma showed different histopathology and immune-profiles of vascular proliferation factors, suggesting they would have different pathological status.
