Internal Medicine

0521779407-14 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 21:16

1014 Multiple Endocrine Neoplasia 2

General Measures

■Established cases:

➣Thyroidectomy for MTC

➣Screen for pheochromocytoma prior to thyroidectomy

➣Evaluate for hypercalcemia

Screening

■RET gene analysis in index case and family members

■Petagastrin-stimulated calcitonin annually in RET mutation (−)

family

■Urine catecholamines and metanephrines yearly

■Calcium (MEN2A) yearly

specific therapy

■MTC: total thyroidectomy; thyroidectomy as early as age 4–7 y for

RET (+) cases or abnormal calcitonin results; in MEN2B, screening

and surgery before age 1 year often recommended continue calci-

tonin screening after surgery; screen for pheochromocytoma prior

to surgery; chemotherapy for metastatic disease

■Pheochromocytoma: adrenalectomy after alpha/beta-blockade

(beta only after alpha) and hydration; bilateral adrenalectomy

possible given high risk of developing contralateral pheochromo-

cytoma

■Hyperparathyroidism: indicated for calcium >11 mg/dL, or end-

organ damage (kidney stones, osteitis, osteoporosis, renal failure,

hypercalciuria); surgical removal of 3 1/2 glands with tagging or

transplant of remaining tissue, hyperplasia of all glands and can have

more than 4 glands

Side Effects

■MTC and thyroidectomy: hypoparathyroidism, recurrent laryngeal

nerve injury, metastatic disease

■Pheochromocytoma and adrenalectomy: hypertensive crisis, recur-

rent tumor, adrenal insufficiency (bilateral adrenalectomy)

■Hyperparathyroidism and parathyroidectomy: hypoparathyroi-

dism, hypocalcemia (hungry bone syndrome), recurrent laryngeal

nerve injury

Contraindications

■Thyroidectomy only after pheochromocytoma ruled out