Segmentally arranged basaloid follicular hamartomas with osseous, dental and cerebral anomalies: a distinct syndrome.

A 39-year-old man presented with multiple basaloid follicular hamartomas involving the right side of his body in a systematized pattern following Blaschko's lines. His right leg was 22.5 cm shorter than the left, and rudimentary pre-axial polydactyly was noted on the left hand and the right foot. The teeth of the right maxilla were hypoplastic. DNA analysis of blood lymphocytes and fibroblasts from lesional skin did not reveal any mutation in the Patched gene. On account of this case and of 8 similar cases found in th e literature, the spectrum of a distinct syndrome is delineated. Ipsilateral extracutaneous defects include cervical ribs, polydactyly, malformed thumb and disproportionate overgrowth or deficient growth of limb bones; dental anomalies in the form of anodontia, hypodontia or ameloblastoma; and cerebral defects such as mental retardation, unsteady gait, meningioma and optic glioma. The cutaneous lesions of this syndrome should not be called "basal cell naevus" as this will lead to continuing confusion with Gorlin syndrome. The molecular basis of the disorder remains to be elucidated.