An Updated Comparison Between World Health Organization Grade II Gemistocytic and Diffuse Astrocytoma Survival and

Adrian Rodrigues1, Michael Zhang1, Angus Toland2

  • 1Department of Neurosurgery, Stanford School of Medicine, Stanford, California, USA.

World Neurosurgery
|November 29, 2021
PubMed
Abstract

Insights

Gemistocytic astrocytoma (GemA) and diffuse astrocytoma (DA) grade II tumors show similar survival rates in recent data. This finding contrasts with older data and may help clinicians counsel patients more accurately.

Area of Science:

  • Neuro-oncology
  • Pathology
  • Epidemiology

Background:

  • The World Health Organization reclassified gemistocytic astrocytoma (GemA) as a diffuse astrocytoma (DA) variant in 2016.
  • Historically, grade II GemA was associated with a poorer prognosis than DA.
  • Diagnostic consistency of GemA over time remains unclear.

Purpose of the Study:

  • To compare survival outcomes between grade II GemA and DA using recent data.
  • To investigate the influence of diagnostic era on the prognostic significance of GemA versus DA.

Main Methods:

  • Analysis of grade II DA and GemA cases from the Surveillance, Epidemiology, and End Results database (1973-2016).
  • Kaplan-Meier survival analysis, focusing on patients diagnosed between 2000-2016.
  • Propensity score matching to balance baseline characteristics between GemA and DA cohorts.

Main Results:

  • Between 2000-2016, GemA constituted 5.35% of grade II astrocytomas.
  • No significant survival difference was observed between GemA and DA patients at baseline (P=0.349) or after matching (P=0.497).
  • Extent of resection benefited DA survival; age >65 was linked to inferior survival for both subtypes.

Conclusions:

  • The prognostic impact of GemA versus DA appears to be influenced by the diagnostic era rather than patient demographics.
  • Recent data indicate no significant survival difference between grade II GemA and DA.
  • Findings can aid clinicians in patient counseling regarding grade II GemA.