Early and rapid progression of GBM is an independent factor with poor prognosis

Gerben R et al.
of the School of Medicine and Health of the University of Manchester in the United Kingdom reviewed the REP-related literature of GBM and conducted a meta-analysis, and concluded that REP is an independent factor with
poor prognosis of GBM.

Article published online
in the June 2022 issue of Neurooncol Adv.

—Excerpted from the article chapter

【Ref: Waqar M, et al.
Neurooncol Adv.
2022 Jun 4; 4(1):vdac075.
doi: 10.
1093/noajnl/vdac075.
】

Research background

The recurrence of glioblastoma (GBM) during surgery and postoperative chemoradiation is called rapid early progression (REP).


The study found that even with total tumor resection (GTR), REP was common and associated with
a decrease in overall survival.

Gerben R et al.
of the School of Medicine and Health of the University of Manchester in the United Kingdom reviewed the REP-related literature of GBM and conducted a meta-analysis, and concluded that REP is an independent factor with
poor prognosis of GBM.

Article published online
in the June 2022 issue of Neurooncol Adv.

Research methods

The investigators searched the research literature related to REP and GBM collected in databases such as MEDLINE, Embase, Web of Science and other databases between the establishment of the database and 21 October 2021 in accordance with the guidelines of the Priority Report Entry (PRISMA) of systematic review and meta-analysis; The inclusion criteria were original articles published in English comparing the
first postoperative MRI scan with pre-radiotherapy MRI scan in GBM patients.

Patient demographics, days between MRI scans, GBM resection range, MRI imaging sequences, and data related to
MGMT promoter methylation, IDH mutation status, and REP were extracted.

The primary endpoint of the study was the incidence of
REP.

Secondary endpoints were the effect of demographic factors and MRI imaging interval on REP, on MRI imaging sequences for the evaluation of REP, on the effect of REP on overall survival (OS), on disease progression and progression-free survival (PFS), on the extent of tumor resection on REP, on MGMT promoter methylation, and on IDH mutation status
.

QUADAS-2 was used to assess literature quality
.

Research results

A total of 9 studies that met the criteria were included, including 7 retrospective and 2 prospective studies, involving 716 patients from 7 countries and regions.
The median age of patients was 56.
9 years (IQR: 54.
0 to 58.
8 years), and the male-to-female ratio was 1.
4 (IQR: 1.
1 to 1.
5).


The median interval between postoperative MRI and preoperative MRI was 34 days (IQR: 18-45 days).


The overall mean incidence of REP was 45.
9% (19.
3% to 72.
0%)
.

82.
5% (85/103) of REP lesions were located in or adjacent areas, and 17.
5% (18/103) were neoplastic lesions far from the surgical site
.

There were no statistically significant differences
between REP and non-REP patients in age (P=0.
62), sex (P=0.
33), and time between MRI imaging (P=0.
27).

In studies that defined REP using only MRI structural sequences, the overall mean incidence of REP was significantly higher than that of studies that defined REP using structural and functional sequences (55.
6%vs.
40.
2%; P＜0.
001）
。
Subtotal resection/biopsy was a significant contributor to the development of REP (OR=6.
96; 95% CI, 4.
51-10.
73; P<0.
001).
<b112>
REP was an independent risk factor for poor prognosis (HR = 2.
10; 95% CI, 1.
83 to 2.
41; P<0.
001).
<b114>
REP was also significantly associated with progression-free survival (PFS) (HR = 1.
78; 95% CI, 1.
30-2.
43; P<0.
001).
<b116>
MGMT promoter methylation was not associated with the incidence of REP (OR=1.
29; 95% CI, 0.
72-2.
28; P=0.
39).


Examination of funnel plots showed clear literature bias on the extent of GBM resection, but not for
other outcomes.

Conclusion of the study

Finally, the authors note that almost half of GBM patients develop REP and that REP is an independent factor
in poor prognosis in GBM patients.