Multimodal treatment with thiotepa, bevacizumab, teniposide, and tunlametinib in a patient with neurofibromatosis type 1-associated oligodendroglioma: a rare case report

Neurofibromatosis type 1 (NF1) is a common autosomal dominant disorder associated with central nervous system gliomas, most frequently optic pathway gliomas; however, oligodendrogliomas in the setting of NF1 are exceedingly rare, with no prior documented cases and no established treatment strategies to date. A 53-year-old female with NF1-associated oligodendroglioma experienced multiple recurrences following surgery, radiotherapy, chemotherapy, and targeted therapy. Upon further disease progression, she was treated with a novel combination of thiotepa, bevacizumab, teniposide, and the mitogen-activated protein kinase kinase 1/2 (MEK1/2) inhibitor tunlametinib. After one treatment cycle, the patient achieved a marked reduction in tumor volume, consistent with a complete response (CR). She subsequently completed eight additional cycles of the regimen and has maintained CR. The treatment was well-tolerated, with manageable grade 3 myelosuppression controlled by supportive care. As of June 2025, the patient has achieved a CR with a progression-free survival of 9 months before experiencing disease recurrence. This rare case of NF1-associated oligodendroglioma was managed with thiotepa, bevacizumab, teniposide, and tunlametinib, highlighting the potential of MEK inhibition in NF1-related gliomas.