Factors in Endocrine Deficiency in Pediatric and Young Adult Patients Receiving Radiotherapy for Brain Tumors


Key Points

  • Endocrinopathy rates were highest in patients treated between 6 and 10 years of age.
  • Endocrinopathy rates were lowest in patients receiving a median radiotherapy dose < 20 Gy to the hypothalamus and pituitary.

In a study reported in the Journal of Clinical Oncology, Vatner et al identified factors associated with an increased risk of endocrine deficiency in pediatric and young adult patients receiving radiation therapy for brain tumors, including hypothalamus and pituitary radiation dose.

Study Details

The study involved dosimetric and clinical data from 189 evaluable children and young adults aged < 26 with brain tumors treated with proton radiotherapy in 3 U.S. prospective studies between 2003 and 2016. Overall, 130 patients (68.8%) with medulloblastoma were treated with craniospinal irradiation and boost, with most of the remaining patients (n = 56) receiving involved-field radiotherapy for ependymoma (13.8%, n = 26) and low-grade glioma (7.4%, n = 14).

Median follow-up was 4.4 years, with a range of 0.1 to 13.3 years. The 4-year actuarial rates of any hormone deficiency and growth hormone, thyroid hormone, adrenocorticotropic hormone, and gonadotropin deficiencies were 48.8%, 37.4%, 20.5%, 6.9%, and 4.1%. Rates of any hormone deficiency increased from 31.3% at 3 years after treatment to 55.5% at 5 years.

Risk Factors

Patients treated between 6 and 10 years of age had a higher rate of endocrinopathy vs patients treated at < 6 years of age, with the lowest incidence of any hormone deficiency observed in those aged > 10 years at the time of treatment (P = .011). Patients aged 6 to 10 years had a higher rate of growth hormone deficiency vs both younger and older patients (P < .0001 for trend), with no significant differences among age groups for other hormones. The risk of any hormone deficiency was lowest among patients who received a median radiotherapy dose to the hypothalamus and pituitary of < 20 Gy (P < .0001 for trend), with the risk of growth hormone (P < .0001), thyroid hormone (P = .00016), adrenocorticotropic hormone (P = .0037), and gonadotropin deficiency (P = .0026) each being lowest with a median dose < 20 Gy.

The investigators concluded, “Median hypothalamic and pituitary radiation dose, younger age, and longer follow-up time were associated with increased rates of endocrinopathy in children and young adults treated with radiotherapy for brain tumors.”

Torunn I. Yock, MD, of the Department of Radiation Oncology at Massachusetts General Hospital, is the corresponding author for the Journal of Clinical Oncology article.

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.