ESPE Abstracts

Introduction: Hypothalamus is a key regulator of hunger and energy expenditure. Children with CNS tumours are at risk of hypothalamic and pituitary dysfunction which could be related to the direct effects of the tumour or treatment.

Aim: To assess the prevalence and severity of obesity in children diagnosed and treated for CNS tumours at a tertiary paediatric centre.

Methods: We retrospectively reviewed case records of all children and young people (CYP) who attended the endo-oncology clinic at our centre over a 12-month period. Anthropometric data were collected at initial presentation, 2, 5, 10years post diagnosis and at the most recent review.

Results: 69 CYP (35M) with an average age of 13.5 (±4.6) years were followed up for a mean duration of 6.7 (±4.4) years. 9.4, 17.0 and 15.1 % of CYP had overweight (BMI>91^st centile), obesity (BMI>98^th centile), and severe obesity (BMI>99.6^th centile) respectively at initial presentation. This increased to 23.2, 20.2 and 18.8% respectively after an average follow up of 6.7 (±4.4) years. The mean BMI-SDS at diagnosis was 1.04 (±1.4) and this progressively increased to 1.26 (±1.3), 1.37 (±1.4) and 1.58 (±1.6) SDS at 2, 5 and 10-years post treatment respectively. There was no significant difference in BMI change between CYP who underwent surgery (ΔBMI-SDS 0.4[±1.2]) and who did not (ΔBMI-SDS 0.2[±0.5]). Similarly, radiation did not change the outcome in terms of weight gain. 9 CYP showed marked increase in BMI-SDS, and poor height velocity and GH deficiency was observed in 77.8% of them. 27 CYP with obesity had shown significant increase in weight SDS (P = 0.001) and BMI-SDS (P = 0.041) between 2 and 5 years after treatment. Children with peri-hypothalamic tumours (n = 33) showed increase in BMI-SDS from 0.9±1.1 at baseline to 1.1±1.3 at 2 years (P >0.05), to 1.4±1.1 at 5 years (P = 0.039) post treatment. This pattern was not observed in other tumours.

Conclusion: Children with CNS tumours tended to develop obesity irrespective of treatment modality (surgery/radiation) in our cohort. Although the typical pattern of acquired hypothalamic obesity (early rapid weight gain) was not frequently observed, the gradual but significant weight gain between 2 and 5 years of treatment could be attributable to milder hypothalamic injury considering the increased prevalence of this pattern in children with peri hypothalamic tumours. This highlights the importance of close monitoring and early intervention in the initial 2 years post diagnosis, to prevent development of obesity and its related complications.