Nevus comedonicus is a rare abnormality of the skin characterized by a unilateral and usually linear distribution of groups of comedones. A case is reported in which lesions extend onto the palmar skin. This is the second case reported in which lesions have involved this area. It is the first case to appear in the American literature and the first case in which there has been a microscopic examination of a lesion of the nonhairy skin.
The literature, particularly that dealing with variant forms of nevus comedonicus, is reviewed. The pathology of the lesions of the hairy and nonhairy skin is described and the histogenesis of nevus comedonicus is discussed.