Final report of Radiation Therapy Oncology Group (RTOG) protocol 9802: Radiation therapy (RT) versus RT + procarbazine, CCNU, and vincristine (PCV) chemotherapy for adult low-grade glioma (LGG)

2006 Background: RTOG protocol 9402 demonstrated improvement in progression-free survival (PFS), but not overall survival (OS) for adult anaplastic oligodendroglioma (O) and oligo-astrocytoma (A) patients (pts) receiving PCV+RT versus (vs) RT alone (Cairncross, JCO 24:2707, 2006). In 1998, a similar study in adult LGG was initiated by RTOG, NCCTG, SWOG, and ECOG. Methods: Eligible criteria: age 40 with any extent of resection, supratentorial WHO grade II A, O, or OA. Pts were stratified by age, histology, KPS, and presence/absence of preop contrast enhancement and randomized to RT alone (54Gy/30 fractions) or RT followed by 6 cycles of standard dose PCV. Reported results include OS rate, median OS time (MOST), PFS rate, median PFS time (MPFST) and hazard ratio (HR). Per study design, survival data are compared using the modified Wilcoxon test (sensitive to early separation of survival curves). The log-rank test (sensitive to late separation of curves) was sub...