Nevus comedonicus of the palm and wrist. Case report with review of five previously reported cases.

Nevus comedonicus (NC) is an uncommon condition consisting of grouped comedo-like papules. Rarely, NC is associated with other structural abnormalities and diseases. Lesions of the palms or soles are distinctly unusual. Histopathologic findings support the concept of a developmental abnormality of the dermal components of the pilosebaceous apparatus with subsequent imperfect differentiation of the epidermal components. Therapy is often unrewarding, although topical tretinoin may be of value.