[Treatment of Lower-Grade Glioma:Emergence of IDH Inhibitors and Changes in Therapeutic Decision-Making]

Lower-grade gliomas comprise a biologically heterogeneous group of adult diffuse gliomas, primarily defined by their molecular alterations. In current practice, management should integrate maximal safe resection, individualized use of radiotherapy, and rational systemic therapy based on the tumor subtype, growth pattern, and anticipated long-term functional outcomes. Surgery remains the cornerstone of treatment because the extent of resection influences tumor control, seizure burden, functional outcomes, and timing of adjuvant therapy. Although radiotherapy is effective, its timing, dose, and field design should be optimized to preserve neurocognitive function and quality of life in patients with prolonged life expectancy. Combined chemoradiotherapy remains essential for select high-risk tumors, whereas temozolomide alone cannot be considered a universal substitute for radiotherapy-based strategies. The emergence of IDH inhibitors, particularly vorasidenib, has expanded therapeutic options for select patients with residual or recurrent non-enhancing grade 2 IDH-mutant gliomas following surgery by prolonging progression-free survival and delaying the need for subsequent intervention, without apparent deterioration in health-related quality of life or neurocognition. This review summarizes current evidence and proposes a practical framework for integrating surgery, radiotherapy, conventional chemotherapy, and IDH inhibition into routine clinical decision-making.