A pigmented papule acting like a playful ghost: dermoscopy of three targetoid hemosiderotic hemangiomas

Targetoid hemosiderotic hemangioma represents an uncommon, distinctive, benign lympho-vascular lesion, with a variable clinical appearance, typically occurs in the lower limbs and trunk. Most patients are in their 20's or 30's. We describe three dermoscopic cases followed by the review of the literature. Dermoscopic images have been collected and have been evaluated for the presence of dermoscopic features. Concerning the review, we researched on pubmed and records were reviewed noting patient age of onset, sex, location, overall size, dermoscopic appearance. The harmonic mean age of patients was 31 years; the female-to-male ratio was 1:1, and the most common locations were lower extremities (47%) and the trunk (29%). In the most recent years several pediatric cases were described, lowering the mean age of the patients in the literature. Most targetoid hemosiderotic hemangioma appear clinically as a small, solitary, reddish-violaceous vascular lesion with a targetoid appearance. The most typical dermoscopic findings are a homogeneous central area, red lacunae, dark lacunae, peripheric red-violaceous ring, whitish structures, peripheric vascular structures, yellowish intermediate areas, and a peripheral pigment network. Histologically, more superficially, in the papillary dermis there are dilated thin blood vessels lined by hobnail-appearing endothelial cells. In the deeper dermis there are typically slit-like capillaries that ramify in the dermis and dissect through collagen bundles. We wanted to evaluate the features of a large series of targetoid hemosiderotic hemangiomas for a better awareness of the entity, to improve its clinical and dermoscopic diagnostic accuracy, to focus attention on nontargetoid patterns, which often mimic other lesions, including melanoma.