Gamma knife radiotherapy in a neurofibromatosis type 1 Chinese pedigrees with NF1 gene frameshift mutation: A case report

RATIONALE: Neurofibromatosis type 1 (NF1) is a common autosomal dominant genetic disorder. NF1 is a multisystemic disease and its pathogenesis involves mutations in the NF1 gene on chromosome 17q11.2 causing RAS overactivation to stimulate abnormal cell proliferation. In this article, a Chinese family with neurofibromatosis type 1 was reported and the relationship between the phenotype and gene mutation was analyzed. PATIENT CONCERNS: The patient was a 9-year-old-male child diagnosed with right eye exophthalmos combined with right eye glioma, optic edema, and peripheral visual field defect. There were multiple cafe-au-lait spots in the whole body of the child. His mother had multiple cafe-au-lait spots, and the eye examination showed no abnormalities. DIAGNOSIS: The proband was diagnosed with NF1 and a heterozygous frameshift mutation (c. 6641delG p. Arg2214Asnfs*30) in the NF1 gene was identified, and his mother also carried the same pathogenic mutation. INTERVENTIONS: To protect the vision of the right eye, he was treated with gamma knife radiotherapy. OUTCOMES: After therapy, his fundus optic disc edema was decreased and the best corrected visual acuity of the right eye was increased. LESSONS: Gene detection is helpful to diagnose the disease and guide the treatment. Gamma knife radiotherapy can preserve better neurological function.