The success of NRG-GBM-RPA: biomarker-based classification, where to next?

Glioblastoma (GBM) is an aggressive primary brain tumor in which outcomes are poor (1). Treatment for GBM had been limited until 2005 with the seminal study by Stupp and colleagues in which the addition of concurrent and adjuvant temozolomide (TMZ) to adjuvant radiotherapy improved median overall survival (mOS) by approximately 2.5 months (2). Since then, radiation therapy with TMZ has been the backbone for management of GBM in the postoperative setting. Initially developed in 1993, the recursive partitioning analysis (RPA) was created to prognosticate patients with high-grade gliomas (including anaplastic astrocytoma and GBM) (3). This classification was further modified and verified in GBM patients treated with radiation and TMZ (1,4).