Osimertinib in Combination with Bevacizumab for EGFR Mutated Recurrent Glioblastoma (GBM): A Case Report

Abstract

Glioblastoma is the most common primary, malignant adult brain tumor with a median overall survival of 12-15 months after diagnosis. The standard of care includes maximal safe resection, chemoradiation, adjuvant chemotherapy with the DNA alkylator, temozolomide and tumor-treating fields. Given the recent advances in targeted molecular therapeutics and tissue sequencing, there is a growing opportunity for precision medicine in GBM treatment. In this case report, we present two patients who were found to have EGFR amplifications on molecular analysis and were treated with the EGFR inhibitor, osimertinib (Tagrisso), in combination with bevacizumab (Avastin) after tumor progression. One patient received osimertinib at first GBM progression, while the other patient received osimertinib after two other treatment regimens had failed. Both patients displayed radiographic stability several months after the expected median overall survival rate of 15 months post-diagnosis for GBM. This case report offers clinical vignettes in support of the use of EGFR inhibitors and bevacizumab in recurrent GBM with EGFR mutations.