Purpose: WHO grade II gliomas are uncommon in patients over the age of 60, and there is a lack in consensus regarding their management. We present molecular tumor characteristics as well as clinical outcomes in patients over the age of 60 undergoing surgical resection of a WHO grade II glioma.
Methods: After receiving IRB approval, patients were identified through the UCSF Brain Tumor Center. Pathologic diagnosis was completed using WHO 2016 grading criteria.
Results: Twenty-six patients with a mean age of 66 years met inclusion criteria with a median follow-up of 5.2 years. Diagnoses included diffuse astrocytoma IDH-mutant (19.2%), diffuse astrocytoma IDH-wildtype (26.9%), Oligodendroglioma IDH-mutant and 1p/19q-codeleted (50%), and a rare case of mixed oligoastrocytoma (3.9%). 66% of astrocytoma IDH-wildtype tumors possessed TERT mutation. Median extent of resection was 75.4%. Progression-free (PFS) and overall survival (OS) were 23.5 and 62.6 months, respectively. Shorter PFS was associated with the astrocytoma IDH-wildtype subtype despite similar extent of resection and adjuvant treatment rates compared to the other subtypes. OS did not differ between subtypes. Malignant transformation and death were associated with larger preoperative and residual tumor volume.
Conclusions: Older patients with diffuse gliomas may safely undergo aggressive treatment with surgical resection and adjuvant therapy. Elderly patients with low grade gliomas have worse clinical outcomes compared to their younger counterparts. This may be due to an increased frequency of diffuse astrocytoma IDH-wildtype tumors in this age group.
Keywords: Elderly; Low-grade glioma; Old age; Surgical resection.