Basal cell nevus syndrome: New mutation of the patched homologue 1 gene

Basal cell nevus syndrome, also known as Gorlin–Goltz syndrome, shows five main pathological features: nevoid basal cell carcinomas; keratocystic odontogenic tumours; congenital skeletal anomalies; calcification of the falx cerebri; and point skin depressions on the palms and/or soles. We encountered a 62-year-old man with basal cell nevus syndrome appearing as multiple cystic lesions in the mandible and maxilla, along with bifid ribs. The multiple cystic lesions were identified on panoramic radiography and computed tomography. Bifid rib was apparent at the left eighth rib on postero-anterior radiography and computed tomography. The multiple cystic lesions were removed by an oral surgery team. Histopathological examination diagnosed the specimens as keratocystic odontogenic tumours. Findings were ambiguous regarding the diagnosis of basal cell nevus syndrome, so the patched homologue 1 (PTCH1) gene was sequenced, identifying a novel mutation (1346T → A). These results strongly suggested that the phenotype had been caused by mutations in the PTCH1 gene. The patient was diagnosed with basal cell nevus syndrome based on genetic investigations. In addition, our findings suggest that a novel mutation (1346T → A) may cause osteoplasty of the mandible, maxilla and ribs.