FLAIR-Only Progression in Bevacizumab-Treated Relapsing Glioblastoma Does Not Predict Short Survival

Abstract

Objectives: In this study, we analyzed the prognostic value of different MRI progression patterns for survival in patients with recurrent malignant glioma treated with the vascular endothelial growth factor antibody bevacizumab. Patients and Methods: Twenty-six adult patients with recurrent malignant glioma treated with bevacizumab or bevacizumab/irinotecan were retrospectively analyzed for the development of contrast-enhanced (T1-weighted MRI) and T2/FLAIR lesions. According to the progression pattern, patients were divided into 3 subgroups: (1) patients with primarily progressive contrast-enhanced lesions in the first MRI after initiation of therapy (‘primary PD group'); (2) patients with stable or regressive enhanced lesions but progressive FLAIR lesions (‘FLAIR-only PD group'), and (3) patients with stable or regressive contrast-enhanced T1 and FLAIR lesions (‘no PD group'). Results: Overall survival (OS) in the 6 patients in the FLAIR-only PD group was not significantly different from the 11 patients in the no PD group (median 311 vs. 254 days, respectively). In contrast, survival in the FLAIR-only PD group was significantly better (p = 0.025) than in the primary PD group. Conclusion: FLAIR-only progression is not an independent prognostic factor negatively influencing OS in recurrent glioblastoma treated with bevacizumab and should not lead to discontinuation of bevacizumab therapy.

Retrospective Analysis of Radiological Recurrence Patterns in Glioblastoma, Their Prognostic Value And Association to Postoperative Infarct Volume

“…Whereas local tumor recurrence is associated with a better prognosis, the remaining recurrence patterns are associated with impaired overall survival 15 . Most studies focused on recurrence patterns in correlation to specific therapy regimes, especially bevacizumab that was thought to be associated with a more invasive recurrence pattern and often FLAIR-only recurrence 22 – 24 , 26 .…”

The role of early magnetic resonance imaging in predicting survival on bevacizumab for recurrent glioblastoma: Results from a prospective clinical trial (CABARET)

“…The sample size of this study limits our ability to determine an association between early T2/FLAIR progression (alone or mixed with other change) and poorer outcomes. Other retrospective studies have resulted in conflicting findings related to whether T2/FLAIR tumor progression is adversely associated with survival . Although several have not found an association, a retrospective analysis of data from patients who participated in the recurrent glioblastoma AVF3708g clinical trial found that a T2/FLAIR assessment was significantly associated with differences in PFS and response rates .…”

“…Other retrospective studies have resulted in conflicting findings related to whether T2/FLAIR tumor progression is adversely associated with survival. [17][18][19] Although several have not found an association, a retrospective analysis of data from patients who participated in the recurrent glioblastoma AVF3708g clinical trial found that a T2/FLAIR assessment was significantly associated with differences in PFS and response rates. 20 Our study has not incorporated advanced MRI techniques such as diffusion restriction, spectroscopy, and cerebral blood volume assessments; it is acknowledged that because of the conflicting studies on the prognostic significance of T2/ FLAIR signal changes, advanced MRI may enlighten investigators and clinicians in this context.…”

Comparison of 2D (RANO) and volumetric methods for assessment of recurrent glioblastoma treated with bevacizumab—a report from the BELOB trial

“…The volumetric methods were also not significantly different from each other. In the past, several studies on the added value of volumetry in recurrent glioblastoma in determining OS have been performed, 11,21,22 most notably by Boxerman et al, 13 in which a direct comparison is made between 2D and volumetric methods. We analyzed all patients together and the bevacizumab-treated patients separately.…”