Neurofibromatosis 1: a novel NF1 mutation in an 11-year-old girl with a giant cell granuloma.

We report an 11-year-old girl who presented with a painless unilateral enlargement of the nasal bridge. Because of multiple café-au-lait spots and a positive family history, neurofibromatosis 1was diagnosed. On a computed tomographic scan, a unilocular radiolucency measuring 1.2 x 2 cm was seen in the anterior wall of the maxillary sinus, which was surgically removed. Histology revealed a central giant cell granuloma. Hyperparathyroidism, which can present with an osseous tumor and similar histology, was excluded. Molecular analysis uncovered a novel splice mutation (A4268G) in this neurofibromatosis 1 family, affecting our patient as well as her mother and brother. This article focuses on the variability of the neurofibromatosis 1 phenotype in this family and the possible relationship between central giant cell granuloma and neurofibromatosis 1.