Standard treatment and experimental targeted drug therapy for recurrent glioblastoma multiforme

Glioblastoma multiforme (GBM) tumors almost invariably recur despite initial treatments. Correct diagnosis using a variety of imaging techniques and the involvement of a multidisciplinary tumor board are critical for evaluating each stage of a patient's progression and determining optimal management. Standard therapies for recurrence generally include repeated resection, radiation therapy, chemotherapy, and supportive care; however, salvage therapy must be highly individualized, and not all patients are eligible for every type of standard therapy. Factors such as the size and location of the tumor, previous treatment, and general health of the patient must be taken into consideration. Although standard therapies can prolong a patient's duration of survival, the median survival time for patients with recurrent GBM is usually less than 1 year. Experimental targeted drug therapies have been developed to inhibit aberrant cell-signaling pathways involved in tumorigenesis, and enrolling patients in clinical trials using these therapies is another option for treatment of recurrent GBM. The use of these novel therapies is often confined to large research institutions, but the severe limitations of standard treatment options make it important to highlight the potential of experimental therapies. In this paper the authors outline standard therapies and review the emerging role of targeted drug therapy in the treatment of recurrent GBM.