Background: For several types of cancer, biological differences and outcome disparities have been documented in adolescents/young adults (AYAs, 15-39 years old) versus children. This study compared clinicopathological features and survival between younger AYAs and children with low-grade glioma (LGG), a common brain tumor among AYAs.
Methods: This was a secondary analysis of Children's Oncology Group legacy study CCG-9891/POG-9130, which enrolled participants 0-21 years of age with newly-diagnosed LGG treated with surgery alone. For analysis, participants were categorized as children (0-14 years old) or early AYAs (eAYAs, 15-21 years old) and compared on demographics, clinical presentation, tumor characteristics, surgical outcomes, progression-free survival (PFS) and overall survival (OS).
Results: Among 468 children and 50 eAYAs, more eAYAs presented with seizures (34.0% vs. 19.2%; p = 0.015), without other significant differences in clinicopathological features. 5-year PFS rates for children and eAYA were 80.2% (95% confidence interval [95% CI], 76.1-83.7) and 83.0% (95% CI 68.8-91.1), respectively; 5-year OS rates were 97.3% (95% CI 95.2-98.5) and 95.4% (95% CI 82.7-98.8), respectively. Multivariable analysis including all participants showed presence of residual tumor to be an independent predictor of PFS (< 1.5 cm3, hazard ratio [HR] 5.93 [95% CI 3.45-10.18]) and (≥ 1.5 cm3, HR 8.38 [95% CI 4.75-14.79]) (p < 0.001), while midline-chiasmatic location (HR 9.69 [95% CI 3.05-30.75], p < 0.001) and non-pilocytic astrocytoma histology (HR 6.77 [95% CI 2.35-19.49], p < 0.001) were independent predictors of OS.
Conclusion: Unlike several other cancers, LGG has similar presenting features and survival for both eAYAs and children. This support continuing a unified treatment approach and enrollment of eAYAs in pediatric clinical trials for LGGs.
Keywords: Adolescent; Children; Glioma; Pathology; Signs and symptoms; Young adult.