“…Thirty-two studies were identified between 1990 and 2012 examining EOR and high-grade glioma patient outcomes (Shibamoto et al, 1990; Vecht et al, 1990; Hollerhage et al, 1991; Phillips et al, 1991; Sandberg-Wollheim et al, 1991; Curran et al, 1992; Duncan et al, 1992; Prados et al, 1992; Dinapoli et al, 1993; Huber et al, 1993; Simpson et al, 1993; Jeremic et al, 1994; Warnke et al, 1994; Nitta and Sato, 1995; Barker et al, 1996; Kowalczuk et al, 1997; Keles et al, 1999, 2006; Buckner et al, 2001; Lacroix et al, 2001; Levin et al, 2002; Puduvalli et al, 2003; Tortosa et al, 2003; Lamborn et al, 2004; Brown et al, 2005; Pope et al, 2005; Stark et al, 2005; Ushio et al, 2005; Nomiya et al, 2007). Most, but not all, studies used standard WHO grading criteria; other grading systems were utilized in a minority of reports (Dinapoli et al, 1993; Levin et al, 2002; Stark et al, 2005).…”