SFEIES24 Poster Presentations Endocrine Cancer & Late Effects (9 abstracts)
1Department of Endocrinology, Beaumont Hospital, Dublin, Dublin, Ireland; 2Department of Medicine, Royal College of Surgeons in Ireland, Dublin, Dublin, Ireland; 3St Lukes Radiation Oncology Network at Beaumont Hospital, Dublin, Ireland
Background: Intensity-modulated radiotherapy (IMRT) precisely delivers radiation to brain tumours while partially sparing surrounding structures like the hypothalamic-pituitary axis. The risk of hypopituitarism in survivors of adult-onset, primary, non-pituitary brain tumours following IMRT is poorly understood.
Methods: We conducted a retrospective cohort study of brain tumour survivors undergoing endocrine surveillance in Beaumont Hospital. Patients with an adult-onset, non-pituitary, brain tumour who received IMRT were included. Endocrine surveillance typically consisted of annual pituitary profiles and either a synacthen or dynamic growth hormone (GH) and cortisol assessment depending on whether patients were GH replacement candidates.
Results: Sixty-nine patients (26 women) were identified with a median age of 38.0 (IQR 30.0-46.2) years at radiotherapy completion. Gliomas were the most common neoplasm (n = 38), followed by meningiomas (n = 17), pinealomas (n = 6), medulloblastomas (n = 5) and other brain tumours (n = 3). Median radiotherapy treatment dose was 54 (IQR 54-60) Gray. Hypopituitarism was diagnosed in 38% (26/69) of patients after a median of 50 (IQR 29-76) months follow up. Among the 30 patients who underwent dynamic GH testing, 63.3% (n = 19) had GH deficiency. The prevalence of ACTH, gonadotropin, and TSH deficiency was 24.6%, 14.5% and 8.7%, respectively. Panhypopituitarism developed in 7.2% (n = 5) of patients. Linear regression analysis revealed a significant association between time following radiotherapy and the likelihood of developing hypopituitarism (OR 1.29 95% CI 1.06-157, P = 0.01), gonadotropin (OR 1.41 CI 1.12-1.34, P < 0.01) and TSH deficiency (1.27 95% CI 1.01-1.63, P = 0.05) but not ACTH (OR 1.12 95% CI 0.93-1.33, P = 0.23) or GH deficiency (OR 1.12 95% CI 0.84-1.49, P = 0.43).
Conclusion: These findings demonstrate a high prevalence of hypopituitarism in survivors of adult-onset brain tumours treated with IMRT; almost two-fifths of patients were affected by 50 months. Long-term systematic endocrine surveillance is essential for early diagnosis and treatment of hormone deficits to potentially improve quality of life and prevent hypopituitarism-related complications.