title: [Study of RET protooncogene in multiple endocrine neoplasm 2A and in familial medullary thyroid carcinoma. Clinical pathological findings in asymptomatic carriers].
abstract: Twenty five percent of the medullary thyroid carcinoma (MTC) is hereditary and 5% is familiar (FMTC), or considered as multiple endocrine neoplasia (MEN) type 2A (17%) or 2B (3%). These diseases are the result of the autosomic dominant inheritance of a mutation in the RET protooncogene, in one out of 12 different known codons. We analyzed 7 families (2 MEN 2A and 5 FMTC). Six mutations were detected in the most frequent codon, 634 (2 MEN 2A y 4 FMTC) and one family with FMTC presented a novel mutation: a transition T > C at codon 630, resulting a C630A change. Among 57 individuals studied, 25 (43.85%) presented the mutation. Seven (28%) were asymptomatic carriers, including 5 children aged 11 +/- 3.2 years. The children underwent total thyroidectomy. The histopathologic examination showed C cells hyperplasia and microcarcinoma focus in both lobes, even in the presence of normal, basal or pentagastrine stimulated, calcitonine levels. In conclusion, we describe a germine novel mutation in the RET protooncogene: C630A; and the corresponding findings of C-cell disease in gene mutated carriers that emphasize the importance of prophylactic thyroidectomy as soon as the molecular diagnosis is confirmed.
authors.affiliation: Instituto Alexander Fleming, División de Endocrinología-Hospital Durand.
authors.forename: Susana
authors.initials: S
authors.lastname: Belli
authors.forename: María E
authors.initials: ME
authors.lastname: Storani
authors.forename: Ricardo J
authors.initials: RJ
authors.lastname: Dourisboure
authors.forename: Ernesto J
authors.initials: EJ
authors.lastname: Podestá
authors.forename: Angela R
authors.initials: AR
authors.lastname: Solano
mesh_terms: D000293:Adolescent; D000328:Adult; D002116:Calcitonin / Q000032:analysis; D018276:Carcinoma, Medullary / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D029721:Drosophila Proteins; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018813:Multiple Endocrine Neoplasia Type 2a / Q000235:genetics*; D009154:Mutation; D010375:Pedigree; D010641:Phenotype; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D051096:Proto-Oncogene Proteins c-ret; D011519:Proto-Oncogenes; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics*; D013964:Thyroid Neoplasms / Q000235:genetics*
chemical_list: D029721:Drosophila Proteins; D011518:Proto-Oncogene Proteins; D002116:Calcitonin; D051096:Proto-Oncogene Proteins c-ret; D020794:Receptor Protein-Tyrosine Kinases; C416649:Ret protein, Drosophila