Early total thyroidectomy in patients with multiple endocrine neoplasia IIb syndrome

Medullary carcinoma of the thyroid gland (MCT) develops at an early age in children with multiple endocrine neoplasia (MEN) IIb syndrome. Prompt diagnosis of the syndrome and early total thyroidectomy offer the only chance for cure. Surgical guidelines for managing the pediatric patient with potential for MCT have included screening with provocative calcitonin tests beginning at one year of age and total thyroidectomy performed when either basal calcitonin or stimulated test levels become abnormal. The diagnosis of MEN IIb, however, can be made on the basis of pathognomic clinical features, including characteristic facies, marfanoid body habitus, submucosal ganglioneuromas and thickened corneal nerves. A family is described herein in which one member had the pathognomonic clinical findings of MEN IIb but did not have an elevated level of serum calcitonin in response to stimulation with pentagastrin and calcium. Nonetheless, a total thyroidectomy was performed and multiple microscopic foci of MCT were found on pathologic examination. This suggests that total thyroidectomy should be performed upon any patient with the characteristic phenotype of MEN IIb, regardless of the results of the stimulation test for calcitonin.