Objective/Introduction: Although a critical chemotherapeutic, temozolomide's optimal
regimen for 2016 World Health Organization (WHO) Grade II gliomas remains elusive,
hence there is utility in not only cataloging survival outcomes of Grade II glioma
subtypes against the background of temozolomide regimens, but also quantifying differences
in progression-free survival (PFS) and overall survival (OS). Materials and Methods: A systematic review of MEDLINE, Embase, and Cochrane Central Register of Controlled
Trails was conducted by using the Preferred Reporting Items for Systematic Reviews
and Meta-Analysis and the Cochrane Handbook of Systemic Reviews of Interventions.
Results: Each molecular subtype of WHO Grade II glioma had a different temozolomide regimen
identified as optimal in prolonging PFS and OS. For PFS, with temozolomide, the 25th, 50th, and 75th percentiles, were as follows (in months), respectively–A-wt II: 6.90, 12.95, and
19.95; A-mt II: 34.45, 36.01, and 39.60; OD II: 37.90, 46.00, and 55.03 (P = 0.016).
For OS, the first quartile (25%), median (50%), third quartile (75%), were respectively
identified (in months–A-wt II: 21.6 (median; n = 1); A-mt II: 60.6, 85.2, and 109.8;
OD II: 86.1, 96.2, and 106.3 (P = 0.37). Conclusion: For each tumor molecular subtype, a different temozolomide regimen was identified
as optimal for prolonging PFS and OS. Furthermore, regardless of temozolomide regimen,
A-wt II had a significantly shorter PFS than A-mt II and OD-II. Overall, the data
can provide useful prognostic insight to patients when making critical treatment decisions.
Moreover, by cataloging and assessing survival outcomes per temozolomide regimen,
such may facilitate future clinical trial design.
Key-words:
Astrocytoma - glioma - low-grade glioma - oligodendroglioma - overall survival - progression-free
survival - temozolomide
