Hypofractionated radiotherapy versus conventional fractionated radiotherapy in elderly patients with glioblastoma multiforme

Abstract

2042 Background: To evaluate efficacy of short- course radiotherapy(RT) in elderly (>60 years) patients with glioblastoma multiforme (GBM), and compare this biological similar short -course radiotherapy with a standard radiotherapy. Methods: Forty-four elderly patients with GBM were randomly assigned after surgery to receive either a short-course of radiotherapy (45 Gy in 15 fractions over 3 weeks) or standard radiotherapy (60 Gy in 30 fractions over 6 weeks) to a target volume described as tumor visible on CT scan and a 2 cm margin. The primary end point was overall survival. Results: The overall response rate and median duration of response were 60% and 8.5 months in short-course RT versus 65% and 8 months in standard RT. Improvement in pretreatment performance status and increase in post-treatment corticosteroid dosage were observed in 50% and 25% in short-course RT versus 40% and 50% in standard RT (P=0.09, P=0.031) respectively. Median survival time was 5.9 months in short-course RT versus 5.6 months in standard RT. Six months, 1-year survival and progression-free survival rates were 40%, 15% and 30% ,10% in short-course RT versus 45%, 10% and 35%, 5% in standard RT, respectively. In both treatment groups, females did significantly better than males, patients with KPS 60–70 did significantly better than those with KPS 50, patients having tumors 4–5 cm did significantly better than those with tumors 6–8 cm as well as did those with more radical surgery when compared to those with biopsy only. On multivariate analysis, only tumor size and extent of surgery were found to independently influence survival. Acute toxicity was generally assessed as mild in the two treatment groups. While RT-induced brain necrosis appeared only in one patient received short- course RT, but this patient died from tumor recurrence. Conclusions: Hypofractionated RT is feasible and safe treatment for elderly patients with GBM. No significant financial relationships to disclose.