Is more better? The impact of extended adjuvant temozolomide in newly diagnosed glioblastoma: a secondary analysis of EORTC and NRG Oncology/RTOG.

Abstract

Background Radiation with concurrent and adjuvant (6 cycles) temozolomide (TMZ) is the established standard of postsurgical care for newly diagnosed glioblastoma (GBM). This regimen has been adopted with variations, including extending TMZ beyond 6 cycles. The optimal duration of maintenance therapy remains controversial. Methods We performed pooled analysis of individual patient data from 4 randomized trials for newly diagnosed GBM. All patients who were progression free 28 days after cycle 6 were included. The decision to continue TMZ was per local practice and standards, and at the discretion of the treating physician. Patients were grouped into those treated with 6 cycles and those who continued beyond 6 cycles. Progression-free and overall survival were compared, adjusted by age, performance status, resection extent, and MGMT methylation. Results A total of 2214 GBM patients were included in the 4 trials. Of these, 624 qualified for analysis 291 continued maintenance TMZ until progression or up to 12 cycles, while 333 discontinued TMZ after 6 cycles. Adjusted for prognostic factors, treatment with more than 6 cycles of TMZ was associated with a somewhat improved progression-free survival (hazard ratio [HR] 0.80 [0.65-0.98], P = .03), in particular for patients with methylated MGMT (n = 342, HR 0.65 [0.50-0.85], P < .01). However, overall survival was not affected by the number of TMZ cycles (HR = 0.92 [0.71-1.19], P = .52), including the MGMT methylated subgroup (HR = 0.89 [0.63-1.26], P = .51). Conclusions Continuing TMZ beyond 6 cycles was not shown to increase overall survival for newly diagnosed GBM.

DOI: 10.1093/neuonc/nox025

Cite this paper

@article{Blumenthal2017IsMB, title={Is more better? The impact of extended adjuvant temozolomide in newly diagnosed glioblastoma: a secondary analysis of EORTC and NRG Oncology/RTOG.}, author={D T Blumenthal and Thierry Gorlia and Mark Gilbert and Michelle Kim and L Burt Nabors and Warren P. Mason and Monika Hegi and Peixin Zhang and Vassilis Golfinopoulos and J. Randolph Perry and Do Hyun Nam and Sara C Erridge and Benjamin Corn and Ren{\'e} Olivier Mirimanoff and P D Brown and Brigitta G. Baumert and Minesh P. Mehta and Martin J. van den Bent and David A. Reardon and Michael Weller and Roger Stupp}, journal={Neuro-oncology}, year={2017}, volume={19 8}, pages={1119-1126} }