The remaining 15 RET mutation carriers did not exhibit CLA; of these, one presented with MTC and pheochromocytoma, nine with MTC only, two with elevated serum calcitonin and three younger subjects with normal serum calcitonin levels.
Adrenomedullin (ADM) is a 52-amino acid peptide with structural homology to calcitonin gene-related peptide (CGRP) initially isolated from human pheochromocytoma.
Here we describe the genetic prenatal testing, the pregnancy management and obstetric outcome in a MEN 2A patient with a right side adrenal hyperplasia and elevated calcitonin levels, a condition suspicious for possible recurrence of pheochromocytoma.
Screening of family members revealed six subjects with medullary thyroid carcinoma or abnormal pentagastrin-stimulated calcitonin test; one had an unilateral pheochromocytoma and two were affected with HSCR.
Prospective screening for early medullary thyroid carcinoma by calcitonin testing and for pheochromocytoma by several techniques routinely permits identification of early manifestations.
None of these 68 subjects had medullary thyroid carcinoma or pheochromocytoma; 6 had elevated plasma calcitonin concentrations and underwent thyroidectomy but had only C-cell hyperplasia.
Expression of the calcitonin (CT)/calcitonin gene related peptide (CGRP) gene and the proopiomelanocortin (POMC) gene has been demonstrated by Northern blot hybridization analysis of RNA extracted from human medullary thyroid carcinoma (MTC), pheochromocytoma and lung carcinoma.
In contrast, of the 14 members in the other 4 family branches, only 4 have had pathologically elevated plasma calcitonin concentrations following alcohol provocation, probably representing C-cell hyperplasia or very early neoplasia and apparently not progressing.None has evidence of phaeochromocytoma.