Response to erlotinib in recurrent glioblastoma multiforme showing coexpression of EGFRvIII and PTEN.

Glioblastoma multiforme (GBM) is the most aggressive brain tumour in adults and remains incurable despite multimodal intensive treatment regimens. We present a patient with a recurrent glioblastoma who showed coexpression of the epidermal growth factor receptor mutant variant III (EGFRvIII) and the tumour-suppressor protein PTEN. She was treated with the tyrosine kinase inhibitor erlotinib for four months, achieving a partial response with improvement of neurologic symptoms. A review of the pertinent literature supporting the future use of therapies against epidermal growth factor receptor (EGFR) in highgrade gliomas is also provided.