Current Standards of Care in Glioblastoma Therapy

ABSTRACT Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. Regardless of ideal multidisciplinary treatment, including maximal surgical resection, followed by radiotherapy plus concomitant and maintenance temozolomide (TMZ), almost all patients experience tumor progression with nearly universal mortality and a median survival of less than 15 months. The addition of bevacizumab to standard treatment with TMZ revealed no increase in overall survival (OS) but improved progression-free survival (PFS). In newly diagnosed GBM, methylation of the O6-methylguanine-DNA methyltransferase (MGMT) promoter has been shown to predict response to alkylating agents, as well as prognosis. Therefore, MGMT promoter status may have a crucial role in the choice of single modality treatment in fragile elderly population. No standard of care is established in recurrent or progressive GBM. Treatment alternatives may include supportive care, surgery, re-irradiation, systemic therapies, and combined modality therapy. Despite numerous clinical trials, the identification of effective therapies is complex because of the lack of appropriate control arms, selection bias, small sample sizes, and disease heterogeneity. Tumor-treating fields plus TMZ represent a major advance in the field of GBM therapy, and should be considered for patients with newly diagnosed GBM with no contraindications. As a disease with such a poor prognosis, treatment of GBM should go beyond improving survival and aim at preserving and even improving the quality of life of both the patient and the caregiver.