An unusual case of schwannomatosis with bilateral maxillary sinus schwannomas and a novel SMARCB1 gene mutation.

Schwannomas are benign tumors that arise from Schwann cells in the peripheral nervous system. Patients with multiple schwannomas without signs and symptoms of neurofibromatosis Type 1 or 2 have the rare disease schwannomatosis. Tumors in these patients occur along peripheral nerves throughout the body. Mutations of the SMARCB1 gene have been described as one of the predisposing genetic factors in the development of this disease. This report describes a patient who was observed for 6 years after having undergone removal of 7 schwannomas, including bilateral maxillary sinus schwannomas, a tumor that has not been previously reported. Genetic analysis revealed a novel mutation of c.93G>A in exon 1 of the SMARCB1 gene.