Endocrine Abstracts

Background: Multiple endocrine neoplasia type 1 (MEN1) is a rare autosomal dominantly inherited condition predisposing to primary hyperparathyroidism (PHPT), pituitary tumors, gastroenteropancreatic tract neuroendocrine tumors (NET), thymic tumours and skin lesions. Clinical features are rare in the paediatric population and guidance exists on the screening for complications of MEN1.

Objective: To describe clinical features and treatment outcomes in a single cohort of MEN1 patients under a tertiary paediatric endocrine centre.

Methods: Demographic and clinical data from patients with confirmed MEN1 mutations who commenced tumour surveillance aged ≤18 years under the Evelina London Children’s Hospital in 2015-2022 were collected and analysed retrospectively. Results are presented as median (ranges).

Results: This cohort included 14 patients (7 Males), aged 12.7 (6.3-17.8) years who had undergone predictive genetic testing (5 paternally, 9 maternally inherited MEN1 mutations) at aged 8.6 (6.4-13.2) years. Tumour surveillance started 0.65 (0-3.3) years post diagnosis. MEN1-related manifestations occurred in 9 (6 Males) patients, with the first abnormality detected aged 13.7 (6.6-16.5) years, among which 6 presented asymptomatically after 4.15 (1.6-5.5) years of screening. PHPT presented in 4 (28%) patients aged 12.0 (6.6-13) years. One patient (aged 17 years) had subtotal parathyroidectomy for persistent hypercalcaemia from parathyroid hyperplasia. Imaging identified pituitary microadenomas (PTA) in 4 (28%) patients aged 14.4 (11.9-15) years including 2 nonfunctioning and 2 microprolactinoma, of which, 1 was treated with dopamine-agonist. Pancreatic tumors were diagnosed in 5 patients aged 12 (10.6-14.7) years including 1 insulinoma, 2 pNET, 2 non-functioning adenomas (<2 cm). The insulinoma patient presented with neuroglycopenic symptoms aged 10.6 years and underwent a partial pancreatectomy at 10.8 years. Two patients had pancreatic NET (pNET) confirmed on tissue biopsies (aged 15.8 and 16.4 years) and were both treated with somatostatin analogues. Concurrent manifestations occurred aged ≤18 years in 3 (21%) patients: PHPT and PTA (n=2); PHPT, PTA and pNET (n=1).

Conclusions: MEN1-related pathology in the paediatric population results in significant morbidity. Our findings highlight the importance of initiating screening early in childhood, recognizing the need to achieve balance between the practicalities, costs and consequences of screening vs the usefulness in identifying and managing pathology.