Multiple Endocrine Neoplasia Syndrome

Question 1

Define multiple endocrine neoplasia syndrome.

Answer 1

Multiple endocrine neoplasia (MEN) syndromes are hereditary tumour syndromes of variable neoplastic patterns and characterised by the development of multiple endocrine tumours.

Question 2

Explain the aetiology/risk factors of multiple endocrine neoplasia syndrome.

Answer 2

Familial cases of MEN
RET proto-oncogene mutation
MEN1 (menin) mutation

Question 3

Summarise the epidemiology of multiple endocrine neoplasia syndrome.

Answer 3

MEN syndromes are relatively rare.

Question 4

Recognise the presenting symptoms of multiple endocrine neoplasia syndrome. Recognise the signs of multiple endocrine neoplasia syndrome on physical examination.

Answer 4

Young age (MEN1/2)
Positive family history (MEN1/2)
Episodic triad of sweating, palpitations, and headache (MEN2)
Clinical features of kidney stones (MEN1/2)
Facial angiofibromas or collagenomas (MEN1)
Mucosal neuromas (MEN2B)
Arm span and upper-to-lower-body-segment ratio (MEN2B)
Palpable thyroid nodule (MEN2)
Irregular menses (MEN1)
Visual changes (MEN1)
Unexplained flushing (MEN2)
Infertility (MEN1)
Clinical features of acromegaly (MEN1)
Clinical features of thyrotoxicosis (MEN1)

Question 5

Identify appropriate investigations for multiple endocrine neoplasia syndrome and interpret the results.

Answer 5

Serum calcitonin (MEN2)
Serum carcinoembryonic antigen (MEN2)
Plasma metanephrines (MEN2)
Serum parathyroid hormone and calcium (MEN1/2)
Fasting serum gastrin (MEN1)
Serum chromogranin A (MEN1)
Serum prolactin (MEN1)
Insulin-like growth factor-1 (MEN1)
24-hour urine metanephrines and catecholamines (MEN2)
24-hour urine calcium (MEN1/2)
Thyroid biopsy (MEN2)