Multiple Endocrine Neoplasia

Question 1

What is multiple endocrine neoplasia?

Answer 1

It is a group of autosomal dominant genetic conditions resulting in the development of neoplasms

Question 2

What are the genetic mutations seen in the different types of MEN syndromes?

Answer 2

MEN 1 is caused by mutation in the MEN1 gene.
MEN-2a and 2b are caused by mutations in the RET oncogene.

Question 3

What malignancy’s are seen in MEN type I?

Answer 3

3 P’s
- Parathyroid tumours (95%),
- Pituitary tumours - prolactinoma and acromegaly/gigantism is most common (lots of milk makes big kids)
- Pancreas tumour eg, insulinoma - causes hypoglycaemia, gastrinoma - causes peptic ulcer disease, Glycagonoma - hyperglycaemia.
- Others: adrenal and thyroid.
- Most commonly presents with hypercalcaemia

Question 4

What are features of MEN IIa?

Answer 4

2 P’s
- Parathyroid (50%)
- Phaeochromocytoma
+ medullary thyroid cancer

Question 5

What are features of MEN IIb?

Answer 5

1 P
- Phaeochromocytoma
+ medullary thyroid cancer
+ Multiple neuromas
- Also presents with marfanoid body habitus and multiple neuromas.

Question 6

What are the differentials for MEN syndromes?

Answer 6

• Non-MEN endocrine neoplasms
• Carney complex: involves endocrine and non-endocrine tumours, skin pigmentation and myxomas.
• Von Hipple-Lindau disease: Haemangioblastomas, renal cell carcinoma or phaeochromocytoma.

Question 7

What is gastrin and where is it produced?

Answer 7

The pancreas produces Gastrin which increases hydrochloric acid production in the stomach

Question 8

What are the investigations for MEN syndromes?

Answer 8

• Genetic testing for mutations in MEN1 or RET genes.
• Hormonal assay to look for excess hormone’s
• CT/MRI to visualize tumours

Question 9

What is the management of MEN syndromes?

Answer 9

• Surgical intervention to remove tumours
• Hormonal therapy to control over production
• Life long surveillance