Skeletal anomalies and keratocysts in the basal cell nevus syndrome.

Five cases with multiple jaw cysts from two families, and two other unrelated patients are presented. Multiple keratocysts of the jaws were found in all patinets whose cysts had been examined histologically. There were also several follicular cysts without keratinization. In some cysts there was even a pronounced proliferation of the basal cells, which resembled basal cell carcinoma. Basal cell carcinomas were seen in only three patients, apparently because the series had been selected for the presence of multiple jaw cysts. However, two patients with only pigmented nevi showed a marked proliferation of the basal cells. An elevation of serum alkaline phosphatase was noted in four out of five patients. The sella turcica was bridged in all but one patient and fusion of the vertebrae was seen in all but two patients. In addition, a high frequency of rib anomalies, frontal and parietal bossing, mild mandibular prognathism and dural calcification was seen. Therefore, what is called the basal cell nevus syndrome may be regarded as a skeletal dystrophy syndrome. Based on the family pedigrees, an autosomal dominant inheritance with poor penetration seems probable.