Radiation therapy for older adults with glioblastoma: radical treatment, palliative treatment, or no treatment at all?

Abstract

The incidence of glioblastoma in older adults has increased over the last few decades. Current treatment includes surgery, radiotherapy, and chemotherapy, but optimal disease management remains a matter of debate. Both standard (60 Gy in 30 daily fractions) and hypofractionated radiotherapy (30-40 Gy in 10-15 daily fractions) have been employed with a similar survival benefit. Recent randomized studies indicate that chemotherapy with the alkylating agent temozolomide is a safe and effective therapeutic option for patients aged 60 years or older with newly diagnosed glioblastoma, suggesting that it should be a sufficient treatment for patients presenting with a methylated O6-methylguanine-DNA methyltransferase (MGMT) promoter gene. The addition of concomitant temozolomide chemotherapy, adjuvant temozolomide chemotherapy, or both to postoperative radiotherapy, which is the standard treatment for adults with glioblastoma, has been associated with a survival benefit for older patients with a good performance status; however, aggressive treatment in this population may be associated with a high risk of neurological toxicity and deterioration of quality of life. Survival stratification according to age, MGMT promoter methylation status, and neurological status may be useful for clinical decision making and designing randomized trials for adequately evaluating the optimal combination of radiotherapy and chemotherapy for older patients with glioblastoma.