Capillary Malformation of Port-Wine Stain

Abstract

BACKGROUND: Cutaneous arteriovenous malformations (AVMs) of stage I may mimic port-wine stains (PWSs) clinicopathologically; therefore, it may be misdiagnosed and mistreated as being PWS. OBJECTIVE: To suggest the clinicopathological differential clues between early AVMs and PWSs. METHODS: A set of 10 radiologically proven AVMs of stage I was selected in conjunction with a set of 10 age-/sex-matched PWSs as a control. Their clinical features, hematoxylin and eosin, CD31, and smooth muscle actin immunohistochemistry were then compared. RESULTS: Four pathological clues for differential diagnosis with statistical significance (P < 0.05) were found: the vessel density (CD31), presence of vascular luminal red blood cells, elongation and haphazard branching of vessels, and thickened vessel walls highlighted by smooth muscle actin. CONCLUSION: Therefore, 4 differential clues with respect to stage I AVM and PWS in their earlier developmental stages have been proposed.