- Radiotherapy (RT) is associated with decreased levels of free thyroxine (FT4) in pediatric/adolescent patients with brain tumors, which might affect weight gain and intelligence scores.
Why this matters
- Study clarifies trends and clinical significance of FT4 concentration in children and adolescents with low-grade glioma or ependymoma.
- FT4 levels decreased over time after RT (−0.00097 ng/dL per month; P<.001>
- Female sex (P<.001 and younger age were associated with greater reductions in ft4 levels multivariate analysis.>
- FT4 decline rate was associated with a greater rate of weight gain (P<.001>
- Lower baseline FT4 was associated with increased risk for glucose disorder (OR, 19.73; P=.002) and dyslipidemia (OR, 19.40; P=.003), but decline in FT4 after RT was not.
- Although intelligence scores improved over time, the rate of improvement was lower in patients with higher rates of FT4 decline (P=.014).
- 267 patients aged ≤25 years with low-grade glioma or ependymoma who were treated with RT were analyzed for FT4 levels.
- Funding: Royal Netherlands Academy of Arts and Sciences and Stichting Kinderen Kankervrij; American Lebanese Associated Charities.
- Observational study design.