Makindo Medical Notes

Related Subjects: |Adrenal Cancer

Most patients with MEN1 present with hypercalcaemia due to primary hyperparathyroidism.

About

• Inherited or sporadic condition also called Wermer syndrome

Aetiology

• AD disorder is caused by mutations in the MEN1 gene on 11q13.
• The MEN1 gene encodes a tumour suppressor protein called MENIN
• Many are sporadic presenting in the 3rd–5th decades

Clinical (see individual topics for more information)

• Parathyroid tumour s: 95%: parathyroid hyperplasia or adenoma. Primary HPTH
• Pituitary tumour s: Prolactinoma or GH Secretion in about 60% of patients.
  • Prolactinomas, growth hormone-producing tumour and ACTH-producing tumour s.
  • Galactorrhoea/infertility (due to prolactinoma), acromegaly or Cushing's disease.
• Pancreatic tumour s: 50-75% of patients with MEN1 develop pancreatic islet cell tumour that include
  • Gastrinoma, Insulinoma, glucagonoma and VIPoma.
  • Zollinger-Ellison syndrome (due to gastrinoma often small, multicentric, and located in the duodenum)
  • Watery diarrhoea with hypokalaemia and metabolic acidosis or Verner-Morrison syndrome (due to VIPoma)
  • Recurrent hypoglycaemia (due to Insulinoma),
  • Hyperglycaemia and necrolytic migratory erythema (due to glucagonoma).
• Occasionally: Carcinoid and adrenal tumour s

Investigations

• FBC, U&E, LFT, Bone
• Ca - hypercalcaemia and low/normal PTH and DEXA scan
• CT abdomen for masses. MRI head for pituitary lesions
• Endoscopy: peptic ulcer disease
• Elevated fasting gastrin level and increased basal gastric acid secretion.
• Hypoglycaemia and elevated Insulin, Elevated C-peptide and proinsulin levels
• Elevated serum glucagon levels
• Elevated serum VIP levels

Management

• Manage tumour detected, Genetic counselling

References