Hypofractionated Stereotactic Radiation Therapy in Recurrent High-Grade Glioma: A New Challenge

The aim of this study was to evaluate outcomes of hypofractionated stereotactic radiation therapy (HSRT) in patients re-treated for recurrent high-grade glioma.

From January 2006 to September 2013, 25 patients were treated. Six patients underwent radiation therapy alone, while 19 underwent combined treatment with surgery and/or chemotherapy. Only patients with Karnofsky Performance Status (KPS) > 70 and time from previous radiotherapy greater than 6 months were re-irradiated. The mean recurrent tumor volume was 35 cm(3) (range, 2.46 to 116.7 cm(3)), and most of the patients (84%) were treated with a total dose of 25 Gy in five fractions (range, 20 to 50 Gy in 5-10 fractions).

The median follow-up was 18 months (range, 4 to 36 months). The progression-free survival (PFS) at 1 and 2 years was 72% and 34% and the overall survival (OS) 76% and 50%, respectively. No severe toxicity was recorded. In univariate and multivariate analysis extent of resection at diagnosis significantly influenced PFS and OS (p < 0.01). Patients with smaller recurren tumor volume treated had better local control and survival. Indeed, the 2-year PFS was 40% (≤ 50 cm(3)) versus 11% (p=0.1) and the 2-year OS 56% versus 33% (> 50 cm(3)), respectively (p=0.26).

In our experience, HSRT could be a safe and feasible therapeutic option for recurrent high grade glioma even in patients with larger tumors. We believe that a multidisciplinary evaluation is mandatory to assure the best treatment for selected patients. Local treatment should also be considered as part of an integrated approach.