Bone health in childhood low-grade glioma: an understudied problem.

Objective: Children with a supratentorial midline low-grade glioma (LGG) may be at risk for impaired bone health due to hypothalamic-pituitary dysfunction, obesity, exposure to multiple treatment modalities, and/or decreased mobility. The presence of impaired bone health and/or its severity in this population has been understudied. We aimed to identify the prevalence and risk factors for bone problems in children with supratentorial midline LGG.

Materials and methods: A retrospective study was performed in children with supratentorial midline (suprasellar or thalamic) LGG between 1 January 2003 and 1 January 2022, visiting the Princess Máxima Center for Pediatric Oncology. Impaired bone health was defined as the presence of vertebral fractures and/or very low bone mineral density (BMD).

Results: In total, 161 children were included, with a median age at tumor diagnosis of 4.7 years (range: 0.1-17.9) and a median follow-up of 6.1 years (range: 0.1-19.9). Five patients (3.1%) had vertebral fractures. In 99 patients, BMD was assessed either by Dual Energy X-ray Absorptiometry (n = 12) or Bone Health Index (n = 95); 34 patients (34.3%) had a low BMD (≤ -2.0). Impaired visual capacity was associated with bone problems in multivariable analysis (OR: 6.63, 95% CI: 1.83-24.00, P = 0.004).

Conclusion: In this retrospective evaluation, decreased BMD was prevalent in 34.3% of children with supratentorial midline LGG. For the risk of developing bone problems, visual capacity seems highly relevant. Surveillance of bone health must be an aspect of awareness in the care and follow-up of children with a supratentorial midline LGG.

Significance statement: Patients with supratentorial midline LGG may encounter various risk factors for impaired bone health. Bone problems in survivors of childhood supratentorial midline LGG are, however, understudied. This is the first paper to address the prevalence of bone problems in this specific patient population, revealing visual problems as an important risk factor. Diencephalic syndrome historyand/or weight problems associated with hypothalamic dysfunction were related to bone problems in univariate analyses. The results of this study can be used in the development of guidelines to adequately screen and treat these patients to subsequently minimizing bone problems as one of the endocrine complications.