3 Predicting Neuropsychological Late Effects in Pediatric Brain Tumor Survivors Using the Neurological Predictor Scale and the Pediatric Neuro-Oncology Rating of Treatment Intensity

Abstract

Objective:

Pediatric brain tumor survivors (PBTS) represent a growing group of childhood cancer survivors vulnerable to adverse neuropsychological outcomes following treatment. Although the identification of risk factors has motivated the efforts to reduce the incidence of neuropsychological late effects in PBTS, most of the prior research on late effects has examined these risk factors on an individually selective basis. Given that tumordirected treatments generally involve a multimodal approach, consisting of a combination of surgical resection, chemotherapy, and/or radiation, and that each patient may have varying degrees of neurological complications, research is needed that focuses on neurocognitive risk factors holistically. The Neurological Predictor Scale (NPS) measures neurological complications associated with neurocognitive risks (e.g., hydrocephalus) and the use of various tumordirected treatment modalities (e.g., craniospinal radiation). The Pediatric Neuro-Oncology Rating of Treatment Intensity (PNORTI) measures the intensity of pediatric brain tumor treatments, but its association with neuropsychological late effects has not been well-established. The present study aims to 1) evaluate treatment intensity as a risk factor for the development of neuropsychological late effects; and 2) expand upon the validity and clinical utility of the NPS and PNORTI as predictive measures for the development of neuropsychological late effects in PBTS.

Participants and Methods:

A retrospective chart review was completed of PBTS (n = 167, M_age = 13.47, SD = 2.80) who were at least 2 years from the end of tumor-directed treatment (surgery, chemotherapy, and/or radiation therapy) and without a multi-system genetic disorder or severe developmental delay prior to brain tumor diagnosis. Neuropsychological outcomes of interest (IQ, processing speed, working memory, verbal comprehension, and perceptual reasoning) were analyzed in relation to the NPS and PNORTI.

Results:

NPS scores ranged from 1 to 11 (M = 5.58, SD = 2.28) and PNORTI scores ranged from 1 (n = 101; 62.7%) to 3 (n = 18; 11.2%). Survivors were on average approximately 6 years post-treatment (M = 6.13, SD = 3.39). Pearson bivariate correlations revealed that NPS scores were significantly correlated with IQ (r = -.20, p = .015) and processing speed (r = -.27, p = .015). Models examining the predictive utility of the NPS on neuropsychological outcomes showed that, when controlling for age at diagnosis and sex, NPS scores significantly predicted IQ [F(3, 147) = 10.83, p < .001, R² = .18, R²adjusted = .16] and processing speed [F(3,88) = 5.62, p = .001, R² = .16, R²adjusted = .13]. A one-way ANOVA showed no significant differences on neuropsychological outcomes based on PNORTI scores.

Conclusions:

The findings suggest that the NPS has value in predicting IQ and processing speed above and beyond demographic variables. However, treatment intensity (PNORTI) was not associated with neuropsychological domains in our sample. Future longitudinal research should examine which specific neurological risk factors within the NPS account for the most variance in neuropsychological outcomes.