Graft-like plantar lesion secondary to possible dorsal-to-ventral cutaneous transposition

We describe a 3-year-old male patient with an unusual congenital lesion on the plantar surface of the left foot that had been asymptomatic until shortly before presentation. Histologic examination of the plaque revealed a thinner keratin layer, increased pigmentation, and a pilosebaceous unit with a visible vellus hair. We tentatively hypothesize from this single case that a disruption in the normal sequence of events of morphogenesis, and particularly in dorsal-to-ventral orientation, may have occurred in this patient.