Outlining the Molecular Profile of Glioblastoma: Exploring the Influence of Subventricular Zone Proximity.

Aim: To investigate the correlation between specific glioblastoma multiforme (GBM) molecular markers and their proximity to the subventricular zone (SVZ) to uncover potential prognostic indicators and therapeutic strategies.

Material and methods: The study retrospectively analyzed 171 patients who underwent surgery for supratentorial GBM from 2016 to 2022. GBMs were categorized into SVZ contact (SVZ + GBM) and SVZ noncontact (SVZ-GBM) groups. We analyzed molecular markers, such as IDH1, P53, ATRX, Ki67, GFAP, and Olig2.

Results: SVZ + GBM tumors were larger (12.2 cm3) than SVZ-GBM tumors (4.8 cm3; p < 0.001). Additionally, IDH1 mutation was negative in 100% of SVZ-GBM tumors; ATRX loss was more prevalent in SVZ + GBM tumors (34.3%) than in SVZ-GBM tumors (4.5%; p < 0.001). There was no correlation between SVZ contact and the p53 value (p=0.134). Furthermore, no difference was observed in the association of the Ki67 proliferation index and Olig2 positivity with SVZ contact (p=0.306, p=0.071, respectively). However, there was a correlation between IDH1 mutation and SVZ contact, with all IDH1-positive tumors showing SVZ contact (p=0.009).

Conclusion: This study revealed a correlation between SVZ contact in GBM and specific molecular markers, specifically IDH1 mutation, ATRX loss, and tumor size. SVZ contact could serve as criterion for categorizing GBMs, thus contributing to an improved understanding of the disease and potential therapeutic interventions.