“Late effects in adulthood are evident even for children with the least malignant types of brain tumors who were treated with the least toxic therapies available at the time,” said M. Douglas Ris, PhD, professor of pediatrics and psychology at Baylor College of Medicine in Houston, in a press release. “As pediatric brain tumors become more survivable with continued advances in treatments, we need to improve surveillance of these populations so that survivors continue to receive the best interventions during their transition to adulthood and well beyond.”
Clinicians generally have assumed that children with low-grade CNS tumors who receive less toxic treatment will have fewer long-term effects than survivors of more malignant tumors who undergo neurotoxic therapies. Yet research has indicated that the former patients can have lasting neurobehavioral or functional morbidity.
Dr. Ris and colleagues invited survivors of pediatric low-grade gliomas participating in the Childhood Cancer Survivor Study (CCSS) and a sibling comparison group to undergo a direct, comprehensive neurocognitive assessment. Of 495 eligible survivors, 257 participated. Seventy-six patients did not travel to a study site, but completed a questionnaire, and the researchers did not include data for this group in their analysis. Dr. Ris and colleagues obtained information about surgery and radiotherapy from participants’ medical records. Patients underwent standardized, age-normed neuropsychologic tests. The primary neuropsychologic outcomes were the Composite Neuropsychological Index (CNI) and estimated IQ. To evaluate socioeconomic outcomes, Dr. Ris and colleagues measured participants’ educational attainment, income, and occupational prestige.
After the researchers adjusted the data for age and sex, they found that siblings had higher mean scores than survivors treated with surgery plus radiotherapy or surgery alone on all neuropsychologic outcomes, including the CNI (siblings, 106.8; surgery only, 95.6; surgery plus radiotherapy, 88.3) and estimated IQ. Survivors who had been diagnosed at younger ages had low scores for all outcomes except for attention/processing speed.
Furthermore, surgery plus radiotherapy was associated with a 7.7-fold higher risk of having an occupation in the lowest sibling quartile, compared with siblings. Survivors who underwent surgery alone had a 2.8-fold higher risk than siblings of having an occupation in the lowest quartile. Surgery plus radiotherapy was associated with a 2.6-fold increased risk of a low occupation score, compared with survivors who underwent surgery alone.
Compared with siblings, surgery plus radiotherapy was associated with a 4.5-fold risk of an annual income of less than $20,000, while the risk for survivors who underwent surgery alone did not differ significantly from that for siblings. Surgery plus radiotherapy was associated with a 2.6-fold higher risk than surgery alone. Surgery plus radiotherapy was also associated with a significantly increased risk for an education level lower than a bachelor’s degree, compared with siblings, but surgery alone was not.
The National Cancer Institute supported the study. The authors had no disclosures.
SOURCE: Ris MD et al. Cancer. 2019 Jun 24. doi: 10.1002/cncr.32186.