Multiple endocrine neoplasia type 2

MEN2 or Sipple's syndrome is caused by the ret oncogene and has three forms. The diagnosis usually refers to MEN2a, comprising medullary thyroid cancer (MTC), phaeochromocytoma and parathyroid tumours. MEN2b comprises MTC, phaeochromocytoma, Marfanoid habitus and mucosal ganglionneuromatosis. Isolated familial medullary thyroid cancer is also caused by ret mutations.

General examination

To diagnose multiple endocrine neoplasia type 2 a detailed and full general examination is mandatory in the initial assessment of all patients.

Marfanoid habitus may be seen in MEN2b.

Blood pressure

Blood pressure will typically be elevated with a phaeochromocytoma, but may revert to normal between attacks.

Skin and mucous membranes

Mucosal neuromas may be seen in the mouth or tongue in MEN2b.

Pruritic cutaneous lichen amyloidosis is located over the upper portion of the back in MEN2a.

Skin tags and freckles may occur in MEN2 or in neurofibromatosis. Neurofibromas may be obvious but cafe au lait patches and axillary freckling should also be sought as they suggest neurofibromatosis.

Neck and lymph nodes

Detailed examination is required to seek evidence of thyroid swelling, lymph nodes or parathyroid masses, even in patients who have already undergone prophylactic surgery.


Gentle examination of the abdomen should be performed for possible adrenal or other masses. Deep palpation is inappropriate as this may trigger an attack.


Fundoscopy should seek signs of hypertensive retinopathy.


Seeking evidence of renal disease due to hypertension or hypercalcaemia.