Comprehensive treatment of severe neurofibromatosis type 1 manifestations in the patient with NF1 mutation: c.240_241del(p.Y80fs)

Background. Neurofibromatosis type 1 (NF1) is an autosomal dominant tumor syndrome characterized by marked polymorphism of clinical manifestations. There is evidence of genotypic correlations in NF1 with more pronounced manifestations of the disease with certain mutations in the NF1 gene. therefore, it is important to describe patients with a specific mutation and a severe NF1 phenotype.

Purpose of the study: to describe the genetic and clinical features of NF1 and its treatment tactics in the patient with severe manifestations of the disease and a unique mutation in the NF1 gene.

Material and Methods. A ten-year-old girl with a sporadic case of NF1 was examined, X-ray examination was performed, a blood sample was taken with DNA extraction and sanger sequencing of the NF1 gene.

Results. The patient was identified to have a unique pathogenic variant c.240_241del(p.Y80fs) in the NF1 gene, and the following clinical manifestations of NF1: retrocerebellar brain cyst, femur plexiform neurofibroma, grade 3 scoliosis, and femur fibrous dysplasia. successful surgical correction of the scoliosis was performed. targeted therapy with selumetinib was prescribed for femur plexiform neurofibroma treatment.

Conclusion. the identified NF1 variant: c.240_241del(p.Y80fs) has not previously been described in the scientific literature and is not included in the ClinVar database. the clinical manifestations of NF1, characterized by severe combined lesions, have been described. treatment of such cases of NF1 requires a combination of targeted therapy and high-tech surgery.

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