Summary

• Hereditary tumour syndromes with distinct patterns of organ involvement.
• Mutations in the MEN1 gene typically cause type 1 multiple endocrine neoplasia (MEN1), and mutations in the RET proto-oncogene typically cause type 2 multiple endocrine neoplasia (MEN2).
• Prophylactic thyroidectomy in childhood is indicated in MEN2.
• Medical management of hormonal hypersecretion is important for symptom control.
• Most tumours require surgical evaluation, although surgical cure is not always possible.
• Genetic carriers require lifelong monitoring, even after successful operations.
• Morbidity and mortality result from both hormonal hypersecretion and metastases.