An autosomal dominant disorder affecting about one in 50,000 individuals. Diagnostic criteria for this type include bilateral cranial nerve VIII tumors or a first-degree relative with type 2, and either a unilateral cranial nerve VIII tumor or two of the following: dermal or subcutaneous neurofibromas, plexiform neurofibroma, Schwannoma, glioma, meningioma, or juvenile subcapsular lenticular opacity.
The 43-year-old woman shown had scattered dermal and subcutaneous neurofibromas together with plexiform neurofibromas of both breasts and left foot. Her mother had bilateral cranial nerve VIII tumors.