Multiple Endocrine Neoplasia type 2B (MEN 2B) an aggresive disease difficult to recognize.

S. IORCANSKY; G. SANSO; A. VIEITES; G. LEVIN; M. BARONTINI

Paris,

Congreso; 14th International Thyroid Congress; 2010

American Thyroid Association

Abstract : Introduction: Multiple endocrine neoplasia type 2 B (MEN 2B), an autosomal genetic syndrome, is an aggresive disease chacterized by peculiar phenotype, medullary thyroid carcinoma (MTC) and pheochromocytoma (50%) that causes early death because of Spreads MTC: Few genetic and clinical studies are available due to the limited number of affected families.  Progress in the field of molecular biology and phenotype recognition have enabled early diagnosis of  RET mutation carriers substantially improving their survival. The unexpected prolonged life-span of these patients has opened concerns about long-term morbidity, reproductive capacity and future of offspring’s. Objetive: The aim of this study is to present genetic, biochemical and clinical studies in a group of MEN 2B patients. Seventeen individuals male 9-females 8 ( aged 6-42 years), from 14 families, 15 index cases and 2 carriers were studied. The two carriers were 7-year-old twins born after ICSI procedure. All individuals presented the characteristic phenotype and the clasical M918T mutation. The medullary thyroid cancer was present in all index cases and also in the two twins in whom prophylactic thyroidectomy was performed. All patients showed increased calcitonin levels before thyroidectomy. After surgery calcitonin levels remained high in all of them. Calcitonin levels were normal before thyroidectomy in the two carriers and became undetectable after surgery. Six patients died from medullary thyroid cancer at ages ranging from 17 to 42 years. Bilateral pheochromocytoma  was present in 5 out of the 15 patients. Increased levels of urinary noradrenaline, adrenaline and their metabolite vanillin mandelic acid were observed in them. Conclusions: Despite all patients presented herein had the same mutation M918T, their evolution was quite variable. Beath before reproductive age is not necessarily a characteristic of patients with MEN 2B. Genetic screening and early diagnosis is highly recommended to avoid its ominous prognosis and to improve outcome of possible offspring.