FLAIR-only progression in bevacizumab-treated relapsing glioblastoma does not predict short survival

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.

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').

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.

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.