This report describes the diagnosis and treatment of a 27-year-old patient with neurofibromatosis 1 (NF1) and late progression of a pre-existing optic pathway glioma (OPG) that caused significant reduction in vision. OPG is one of the diagnostic criteria for establishing the diagnosis of NF1. Most common findings of NF1 are café-au-lait spots, axillary and inguinal freckling of the skin, iris hamartoma (Lisch nodules), and tumors of the central nervous system and peripheral nerves. We successfully applied a modified International Society of Paediatric Oncology chemotherapy regimen for low-grade glioma in children with carboplatin dose adjustment according to the area under the plasma drug concentration-time curve calculation. During and after the chemotherapy, a clear improvement of the visual capacity was achieved. Age-adapted chemotherapy for symptomatic adult-onset OPG in patients with NF1 should be considered in individual cases.
