[Multiple endocrine neoplasia type 2b. Clinical, diagnostic and therapeutic aspects].

Multiple Endocrine Neoplasia type 2b (MEN 2b) is a rare syndrome. The principal features are: medullary thyroid carcinoma (MTC), dysmorphism, a ganglioneuromatosis and pheochromocytomas. Eight cases of MEN 2b have been observed at the Institute Gustave Roussy, between 1968 and 1983. Seven involved children under 15 years of age. Eight had a bilateral MTC; six had dysmorphism; six had mucosal tongue neuromas. Six were troubled with visceral ganglioneuromatosis of whom two had intestinal obstruction and one urinary chronic retention. One patient had pheochromocytoma with hypertension. From this experience and other data it appears that: the dysmorphism is frequently poorly interpreted; the visceral ganglioneuromatosis is an early and severe feature; it is important to examine the patient for pheochromocytoma; the MTC must be detected by calcitonin dosage after stimulation, and requires total thyroidectomy; familial screening must be done. To improve the poor prognosis of MEN 2b, early diagnosis and aggressive treatment are necessary.