Multiple Endocrine Neoplasia Type 1

Multiple Endocrine Neoplasia Type 1 (MEN1) Sequencing and Deletion/Duplication 2005360
Method: Polymerase Chain Reaction/Sequencing/Multiplex Ligation-dependent Probe Amplification

Preferred initial test to confirm diagnosis of MEN1

Multiple Endocrine Neoplasia Type 1 (MEN1) Sequencing 2005359
Method: Polymerase Chain Reaction/Sequencing

Acceptable initial test to confirm diagnosis of MEN1

Familial Mutation, Targeted Sequencing 2001961
Method: Polymerase Chain Reaction/Sequencing

Useful when a pathogenic familial variant identifiable by sequencing is known

See Related Tests for tumor testing and screening including anterior pituitary and carcinoid tumor testing, gastrinoma testing, medullary thyroid carcinoma testing, pancreatic neuroendocrine tumor testing, parathyroid tumor testing, and pheochromocytoma testing.

Multiple endocrine neoplasia type 1 (MEN1) is a hereditary syndrome caused by pathogenic variants in the MEN1 gene and is associated with a combination of endocrine and nonendocrine tumors. In MEN1, tumors are most often found in the parathyroid gland, islet cells of the pancreas, and pituitary gland. Tumors can also form in other endocrine glands and the digestive tract. The majority of MEN1 tumors are benign but tumors of the gastroenteropancreatic tract and thymic carcinoids may be malignant. Endocrine tumors cause an increased hormone production based on tumor type, resulting in a wide range of symptoms.

Disease Overview




  • MEN1 can include development of multiple endocrine and nonendocrine tumors 
  • Common endocrine tumors:
    • Parathyroid
    • Gastroenteropancreatic tract (gastrinoma, insulinoma, glucagonoma, pancreatic islet cell tumor)
    • Pituitary (prolactinoma)
    • Gastrinoma
    • Carcinoid (thymic, bronchial, gastric)
    • Adrenal
    • Medullary carcinoma of the thyroid
  • Nonendocrine tumors:
    • Facial angiofibromas
    • Collagenomas
    • Lipomas
    • Meningiomas
    • Ependymomas
    • Leiomyomas





Autosomal dominant



  • ~50% by 20 years
  • >95% by 40 years

De novo variants: ~10%


Inactivating variants of MEN1 tumor suppressor gene

Test Interpretation

Clinical Sensitivity

Combined testing: ~94%

  • Sequencing: 90% 
  • Deletion/duplication: 4% 


  • Positive:
    • One pathogenic variant detected in MEN1
    • Confirms diagnosis and etiology of MEN1
  • Negative:
    • No detectable pathogenic variant detected in MEN1
    • Reduces, but does not exclude, a diagnosis of MEN1
  • Uncertain: variants of unknown clinical significance may be detected


  • Not evaluated:
    • Regulatory region or deep intronic variants
    • Breakpoints of large deletions/duplications
    • Variants in genes other than MEN1
  • Diagnostic errors can occur due to rare sequence variations
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  4. Online Mendelian Inheritance in Man. Multiple Endocrine Neoplasia Type 1. Online Mendelian Inheritance in Man. Johns Hopkins University [Edit: Feb 2017; Accessed: Sep 2019]
  5. Bassett JH, Forbes SA, Pannett AA, Lloyd SE, Christie PT, Wooding C, Harding B, Besser GM, Edwards CR, Monson JP, Sampson J, Wass JA, Wheeler MH, Thakker RV. Characterization of mutations in patients with multiple endocrine neoplasia type 1. Am J Hum Genet. 1998; 62(2): 232-44. PubMed
  6. Carroll RW. Multiple endocrine neoplasia type 1 (MEN1). Asia Pac J Clin Oncol. 2013; 9(4): 297-309. PubMed
  7. Thakker RV, Newey PJ, Walls GV, Bilezikian J, Dralle H, Ebeling PR, Melmed S, Sakurai A, Tonelli F, Brandi ML, Endocrine Society. Clinical practice guidelines for multiple endocrine neoplasia type 1 (MEN1). J Clin Endocrinol Metab. 2012; 97(9): 2990-3011. PubMed

Last Update: September 2019