Neuroendocrine late effects after tailored photon radiotherapy for children with low grade gliomas: Long term correlation with tumour and treatment parameters

Purpose To evaluate neuroendocrine late effects in paediatric patients with low grade glioma (LGG) who underwent radiotherapy. Methods and material We performed a retrospective evaluation of 40 children with LGG treated from July 2002 to January 2015 with external radiotherapy. Tumour locations were cerebral hemisphere (n = 2); posterior fossa (n = 15); hypothalamic–pituitary axis (HPA, n = 15); spine (n = 5). Three patients presented a diffuse disease. We looked for a correlation between endocrine toxicity and tumour and treatment parameters. The impact of some clinical and demographic factors on endocrinal and neuro toxicity was evaluated using the log-rank test. Results The median follow-up was 52 months (range: 2–151). Median age at irradiation was 6. The dose to the HPA was significantly associated with endocrine toxicity (P value = 0.0190). Patients who received chemotherapy before radiotherapy and younger patients, showed worse performance status and lower IQ. The 5-year overall survival (OS) and progression free survival (PFS) rates were 94% and 73.7%, respectively. Conclusion Radiotherapy showed excellent OS and PFS rates and acceptable late neuroendocrine toxicity profile in this population of LGG patients treated over a period of 13 years. In our experience, the dose to the HPA was predictive of the risk of late endocrine toxicity.