Characteristics of gliobastomas (GBM) not resected (only biopsied) homogeneosuly treated with Stupp regimen. Results from the GLIOCAT study

Background

Prognosis of GBM is especially poor for unresected patients even when treated with the standard EORTC regimen.

Methods

We analyzed clinical characteristics, median progression free survival (PFS) and median overall survival (OS) of unresected patients from the database of the GLIOCAT study (432 patients uniformly treated with the EORTC regimen).

Results

Sixty-five patients began concurrent therapy. OS for all patients who started treatment was 7.2 months (95% CI:4.3-10.2). Fourteen patients could not even complete the concomitant phase (TMZ + RxT) (21.5%). Fifty-one patients (78.5%) completed concomitant treatment and are described here. Median age: 61 years old (29 males and 22 females). Multifocal tumor in 12 patients. Median lapsed time to start RT: 4 weeks. PFS was 6 months (95% CI: 3.9-8.03) and OS was 9 months (95% CI:6.4-11.5). MGMT status was available for 31 patients. OS and PFS were 12 months (95% CI: 5.1-18.7) and 8 months (95% CI: 6.5-9.4) for mMGMT vs 7 months (95% CI: 1.1-12.8) and 5 months (95% CI: 3.2-6.7) for mMGMT (NS). Only age (older than ≥50) emerged as a poor prognostic factor: OS 8 (95% CI: 5.7-10.2) vs. 19 (95% CI: 9.4-28.5); P = 0.05. Treatment at recurrence was administered to 20 patients (30.7%). OS and PFS for those patients was 18 months (95% CI: 15.3-20.6) and 7 months (95% CI: 5.9-8.0), respectively, compared with 6 months (95% CI: 5.0-6.9) and 4 months (95% CI: 1.6-6.3) for patients without a second line treatment.

Conclusions

Median OS for unresected patients treated with the standard treatment is similar to that reported in the pivotal trial. However, 21.5% could not even complete concurrent therapy, and only 30.7% could receive a second line therapy.

Clinical trial identification

Legal entity responsible for the study

GLIOCAT

Funding

GLIOCAT

Disclosure

All authors have declared no conflicts of interest.