Tumor Location and Survival Outcomes in Adult Patients with Supratentorial Glioblastoma by Levels of Toll-Like Receptor 9 Expression.

Abstract

Toll-like receptor 9 (TLR9) is a key immunotherapy target for glioblastoma (GBM). This study explored the correlation of TLR9 expression with tumor location and survival outcomes in patients with supratentorial GBM. We retrospectively identified 46 patients with supratentorial GBMs and divided them into those with high TLR9 (TRL9^High) and low TLR9 (TRL9^Low) levels. The 2 groups were compared by patients' ages, sex, preoperative Karnofsky Performance Scale (KPS) score, resection extent, tumor location, progression-free survival (PFS), and overall survival (OS). The TLR9 expression percentages for the GBM specimens were TRL9^High: 72% (33/46) and TRL9^Low: 28% (13/46). The 2 groups showed no differences in patient age (P = 0.147) and sex (χ² = 0.002, P = 0.966), preoperative KPS score (χ² = 0.033, P = 0.855), or resection extent (χ² = 2.405, P = 0.121). Location differed significantly, with 85% (11/13) of TRL9^Low tumors in the left hemisphere and 45% (15/33) of TRL9^High tumors on the same side (χ² = 5.82, P = 0.016). The TRL9^Low group had a median PFS of 612 days (range, 77-926 days), significantly longer than the TRL9^High group (355 days; range, 105-861 days; P = 0.042). Median OS of the TRL9^Low group (733 days; range, 163-969 days) was also significantly longer than in the TRL9^High group (396 days; range, 135-1024 days; P = 0.020). Patients with TRL9^Low supratentorial GBM tend to have longer survival than those with higher TLR9 expression. Such tumors show a location preference for the left hemisphere.