Predictors of cognitive function in pediatric brain tumor patients: Pre-surgery through 24-month follow-up

Abstract

The aim of this study was to examine the feasibility of cognitive assessment from pre-surgery through 2-year follow-up in a sample of pediatric brain tumor (BT) patients. We sought to investigate cognitive function over the course of diagnosis and treatment, and as a function of presenting problems, tumor location, treatment type, and tumor severity. Using a prospective, longitudinal design, standardized IQ measures were administered to pediatric BT patients (ages 6–16) prior to surgery (n = 25), 6 months post-diagnosis (n = 24), and 24 months post-diagnosis (n = 23). Group differences emerged based on tumor severity and treatment type at multiple time points, including prior to surgical intervention; children with high grade tumors performed more poorly than children with low grade tumors, and children receiving surgery plus adjuvant therapy performed more poorly than children who received surgery only. When considered together, an analysis of covariance demonstrated that tumor grade significantly accounted for variability in cognitive functioning, while treatment type did not. Although there is overlap clinically between tumor severity and treatment received, results suggest that tumor severity is an important factor contributing to variability in cognitive functioning and should also be considered when monitoring risk for cognitive deficits in children diagnosed with BT.

Keywords:

• Cancer
• longitudinal assessment
• medical predictors
• oncology
• risk factors

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Notes

1 Of note, FSIQ, including working memory and processing speed subtests, was significantly lower than the calculated GAI, which does not include working memory and processing speed subtests, at T2, t = 4.50, p < .001, and at T3, t = 3.60, p = .002, each by approximately four IQ points. Therefore, all analyses were conducted with both GAI and FSIQ calculated from the standard 10 subtests administered from the WISC-IV at T2 and T3 in order to ensure that cognitive function across time points was comparable, and also account for potential effects altered by the inclusion of working memory and processing speed subtests which were only assessed at T2 and T3. Of note, all results but one remained significant when using FSIQ vs. GAI and is noted.

2 All analyses with run both with and without the two participants who had died over the course of the study. One participant had completed only a T1 assessment and the other had only completed a T2 assessment, as noted in Supplementary Table 1. No results changes as a result of their exclusion, therefore all results include these data where applicable.

3 This is the one result that became non-significant when using FSIQ, F(1,23) = 2.55, p = .10, instead of GAI.

Additional information

Funding

This research was supported by a gift from an anonymous donor and in part by a grant from the National Cancer Institute [R21 CA175840].