The Role of Radiation Therapy in the Treatment of High Grade Gliomas - Abstract
High grade gliomas (HGG) account for the majority of primary central nervous system tumors and are infiltrative tumors with microscopic disease extending into the adjacent brain paranchyma, characterized by aggressive growth and poor prognosis. Patients are managed in a multidisciplinary team setting in order to ensure their care is guided by the most current evidenced based treatments. Currently accepted adjuvant management includes maximal surgical resection or biopsy followed by concomitant Temozolamide and radiation (a total dose of 60 Gy administered in 30 fractions) followed by 6 cycles of adjuvant Temozolamide. The outcome in patients with HGG is still poor, tumors recur in the majority of patients and the disease is most often fatal. Therefore there is a need to develop new treatment regimens and technological innovations to improve overall survival in patients with HGG. Since most the recurrences occurring within the previous irradiation field new regimes designed to deliver higher dose. Several studies used hyperfractionated or accelerated regimens as a means to escalate dose; however there is insufficient data regarding hyperfractionation/accelerated radiation versus conventionally fractionated radiation. Recently, the role of novel radiation techniques such as stereotactic radio surgery (SRS) or stereotactic radiotherapy (SRT) investigated in HGG patients both in newly diagnosed patients as well as the recurrent setting; however there is insufficient evidence in terms of the benefits/harms of using SRS/SRT. This review discusses the role of the RT in the treatment of HGG by the light of current standards, new concepts, and innovations in RT.