Prospective, longitudinal comparison of neurocognitive change in pediatric brain tumor patients treated with proton radiotherapy versus surgery only

Abstract

Background. Proton radiotherapy (PRT) reduces the volume of normal tissue receiving radiation dose, which may lead to better neurocognitive outcomes. We examined change in neurocognitive scores over time in pediatric brain tumor patients treated with proton craniospinal irradiation (CSI), proton focal RT, or surgery only. Methods. Patients received annual neurocognitive evaluations for up to 6 years. We examined Full Scale IQ (FSIQ), Verbal Comprehension Index (VCI), Perceptual Reasoning Index (PRI), Working Memory Index (WMI), and Processing Speed Index (PSI) scores. General linear mixed models examined change in scores over time by treatment group, adjusting for significant covariates. Results. Scores from 93 patients treated between 2012 and 2017 (22 proton CSI, 31 proton focal, and 40 surgery only) were examined. Treatment groups were similar on gender (51.6% male), age at treatment (median = 9.7 y), and length of follow-up (median = 2.9 y). The surgery only group had proportionately more gliomas (P < 0.001), and the proton CSI group had more infratentorial tumors (P = 0.001) and higher total RT dose (P = 0.004). The proton focal and surgery only groups exhibited stable neurocognitive scores over time across all indexes (all P > 0.05). In the proton CSI group, WMI, PSI, and FSIQ scores declined significantly (P = 0.036, 0.004, and 0.017, respectively), while VCI and PRI scores were stable (all P > 0.05). Conclusions. Focal PRT was associated with stable neurocognitive functioning into survivorship. Outcomes were similar whether patients received focal PRT or no radiotherapy, even in neurocognitive domains known to be particularly radiosensitive. Proton CSI emerged as a neurocognitive risk factor, consistent with photon outcomes research.

Long‐term cognitive and academic outcomes among pediatric brain tumor survivors treated with proton versus photon radiotherapy

“…This study provides further evidence of good outcomes following focal PRT, consistent with extant research. 14,15,24 15). Results depict least square means adjusting for covariates (focal group covariates: shunt, interval between RT and evaluation, and total radiation dose; CSI group covariates: posterior fossa boost, Lansky/Karnofsky score, interval between RT and evaluation, and CSI dose).…”

Early radiotherapy preserves vision in sporadic optic pathway glioma

“…This should not be surprising, as it known that patients with pilocytic astrocytoma histology (as seen in many cases of OP/HG) have greater than fivefold odds of developing pseudoprogression compared with other LGGs undergoing photon RT (29%) and this may be further increased by the use of PBT 16,32 . Clinical data supporting the neurocognitive outcomes of PBT versus photon beam therapy are emerging; children treated with focal PBT may have few differences in this domain compared with those who do not receive RT 33‐35 . Although we have focused on visual outcomes in this study, long‐term quality of life and cognitive outcomes are a critical next step of study in the OP/HG population treated early or late with PBT.…”

World Cancer Day 2021 - Perspectives in Pediatric and Adult Neuro-Oncology

“…Proton Beam Therapy (PBT), where available, has become the standard of care for some pediatric brain tumors, especially with the demonstration of improved outcomes with respect to hearing loss, neuroendocrinology and especially neurocognition (57)(58)(59)(60)(61). Craniospinal irradiation delivered via PBT has the advantages of relative sparing of the esophagus, bladder and bowel.…”