Long term responses with cetuximab therapy in glioblastoma multiforme

Glioblastoma multiforme (GBM) is responsible for most of the deaths associated with primary brain tumors. Standard treatment includes maximal surgical resection followed by chemotherapy and concomitant radiotherapy. Most patients, however, recur shortly after treatment. Second line treatment has little efficacy and the majority of patients die soon from the disease. Recent advances in molecular biology have implicated the epidermal growth factor receptor (EGFR) signaling pathways in the progression and resistance to standard therapies for GBM. This has prompted the evaluation of EGFR tyrosine-kinase inhibitors with encouraging results. Cetuximab is a monoclonal antibody targeted against the extracellular domain of the EGFR with activity against different tumor types, either alone or in combination with chemotherapy and/or radiation therapy. Here we describe three patients with recurrent, heavily pretreated, EGFR expressing GBM who responded to treatment with single agent cetuximab.