Biopsy Versus Subtotal Versus Gross Total Resection in Patients with Low-Grade Glioma: A Systematic Review and Meta-Analysis

BACKGROUND: The role of the extent of surgical resection (EOR) in clinical outcomes for patients with low-grade glioma requires further examination. The goal of the present study was to evaluate the association between variable degrees of EOR and clinical outcomes for patients with low-grade glioma. METHODS: We conducted a systematic review and meta-analysis and searched databases for reports of low-grade glioma EOR. Eligible studies compared patient outcomes, including >= 2 categories of EOR (biopsy, resection of any extent, subtotal resection [STR], or gross total resection [GTR]). Treatment effects were evaluated using pooled estimates, mean differences, or risk ratios (RRs) with corresponding 95% confidence intervals (CIs) using random effects modeling. RESULTS: Our literature search yielded 60 studies with 13,289 patients. Pooled estimates of overall survival (OS) showed an increase from 3.79 years in the biopsy group to 6.68 years in STR to 10.65 years in GTR. OS was favorable with resection of any extent compared with (mean difference, 3.24; 95% CI, 0.64-5.84; P = 0.015). Pooled estimates of seizure control showed an improvement from 47.8% with biopsy to 54.2% with STR and 81.0% with GTR. Compared with STR, GTR delayed malignant transformation (RR, 0.43; 95% CI, 0.20-0.93; P = 0.032), without increasing postoperative mortality (RR, 0.38; 95% CI, 0.07-1.97; P = 0.250) or morbidity (RR, 1.22; 95% CI, 0.65-2.28; P = 0.540). CONCLUSION: Among patients with low-grade gliomas, greater degrees of safe EOR were associated with longer OS and progression-free survival, better seizure control, and delayed malignant transformation, without increasing mortality or morbidity.