Factors associated with a higher rate of distant failure after primary treatment for glioblastoma

Abstract

Our purpose was to analyze the pattern of failure in glioblastoma (GBM) patients at first recurrence after radiotherapy and temozolomide and its relationship with different factors. From 77 consecutive GBM patients treated at our institution with fluorescence guided surgery and standard radiochemotherapy, 58 first recurrences were identified and included in a retrospective review. Clinical data including age, Karnofsky performance score, preoperative tumor volume and location, extend of resection, MGMT promoter methylation status, time to progression (PFS), overall survival (OS) and adjuvant therapies were reviewed for every patient. Recurrent tumor location respect the original lesion was the end point of the study. The recurrence pattern was local only in 65.5% of patients and non-local in 34.5%. The univariate and multivariate analysis showed that greater preoperative tumor volume in T1 gadolinium enhanced sequences, was the only variable with statistical signification (p < 0.001) for increased rate of non-local recurrences, although patients with MGMT methylation and complete resection of enhancing tumor presented non-local recurrences more frequently. PFS was longer in patients with non-local recurrences (13.8 vs. 6.4 months; p = 0.019, log-rank). However, OS was not significantly different in both groups (24.0 non-local vs. 19.3 local; p = 0.9). Rate of non-local recurrences in our series of patients treated with fluorescence guided surgery and standard radiochemotherapy was higher than previously published in GBM, especially in patients with longer PFS. Greater preoperative enhancing tumor volume was associated with increased rate of non-local recurrences.

Fig. 1

63 years-old female with GBM. MRI at diagnosis (upper row) and first recurrence (lower row). At diagnosis a left parieto-occipital mass was found, hyperintense in T2 FLAIR (arrow in a) and with irregular peripheral enhancement with central necrosis in T1Gd (arrow in b), with normal left temporal lobe (c and d). 13 months after surgery there was no evidence of recurrence at the surgical cavity borders with only treatment-related changes, with gliosis in T2 FLAIR (arrow in e) and a small stable area on enhancement in T1 Gad (arrow in f). Yet a new remote nodule appeared in the left temporal lobe, outside the radiation field (arrows in g and h), confirmed to be a GBM recurrence after surgery

Fig. 2

Kaplan–Meier curves for progression free survival (PFS) and overall survival (OS)