A vascular lesion in the papillary dermis resulting from ectasia of pre-existing vessels. It is associated with secondary proliferative changes in the overlying epidermis (hyperkeratosis). It can present with widespread lesions (angiokeratoma corporis diffusum, often associated with inborn errors of metabolism) or as a localized lesion (angiokeratoma of Fordyce, angiokeratoma circumscriptum, and angiokeratoma of Mibelli).