Risk stratification of pediatric high-grade glioma: a newly proposed prognostic score

High-grade glioma (HGG) is a clinical challenge. Radiation Therapy Oncology Group Recursive Partitioning Analysis (RTOG-RPA) for HGG remains the standard for assessing the prognosis of adult HGG. This study assesses the validity of the RTOG-RPA to be applied to pediatric HGG.

A retrospective study was conducted on 59 pediatric HGG treated in the Children's Cancer Hospital, Egypt (CCHE) between 2007 and 2016. Several factors were studied as predictors for the disease survival, including age, gender, increased intracranial hypertension, tumor characteristics and pathology, CSF seeding, performance status, post-surgical residual, and radiation dose. The statistically significant results were integrated into a Cox-regression model to develop a prognostic risk score.

Kaplan-Meier statistics identified 13 factors that impacted the overall survival. However, Cox model showed that the histological grade IV [HR 14.2, 95%CI; (3.5-57), P < 0.0001], thalamic infiltration [HR 8.7; 95%CI; (2.9-25.9), P < 0.0001], PS ≥ 60 [HR 0.317; 95%CI; (0.13-0.776); P = 0.012], and maximum tumor dimension > 3.3 cm [HR 10.2; 95%CI; (1.58-65.89); P = 0.015] were the independent variables that predicted the overall survival. A risk score was proposed based on the presence of one or more of these factors. The median OS for the low risk (score 0-1), the intermediate-low risk (score 2), the intermediate-high risk (score 3), and the high risk (score 4) were 40, 18.5, 9.5, and 2.5 months, respectively, (P < 0.0001).

The proposed model and risk score could stratify pediatric patients as the RTOG-RPA do for the adults.