Long-term survival in a patient with Li-Fraumeni syndrome-associated giant cell glioblastoma treated with nivolumab: illustrative case.

backgroundLi-Fraumeni syndrome (LFS) is characterized by p53 germline mutations and a high predisposition to cancers including glioblastoma (GBM), the most common and aggressive primary malignant brain tumor in adults. Despite current therapies, the 5-year survival rate is 5%-10%. The authors report a case with a durable long-term response to immunotherapy with checkpoint inhibition in a patient with LFS-associated GBM. OBSERVATIONS: An 18-year-old female presented after a syncopal episode and left leg weakness and was found to have a right frontal tumor. She underwent gross-total resection of the tumor (grade IV giant cell GBM IDH-wildtype, MGMT unmethylated, associated with a p53 germline mutation), radiation, and chemotherapy. On later imaging, increased enhancement was demonstrated, which raised concerns for tumor recurrence, and she underwent stereotactic radiosurgery followed by lomustine and procarbazine. These agents were later replaced with bevacizumab after a second resection, negative for recurrent glioma. Subsequently, nivolumab was added, given concerns for tumor progression, and the patient showed improvement within 5 months. The patient has continued nivolumab monotherapy and has had progression-free survival for more than 7 years. LESSONS: Despite advances in treatment, the median survival of patients with GBM is only 15 months. This case highlights the potential of immunotherapy with PD-L1 checkpoint inhibition in improving outcomes for LFS-associated GBM patients. https://thejns.org/doi/10.3171/CASE24539.