Sporadic medullary thyroid carcinoma: clinical data from a university hospital.

Introduction: Medullary thyroid carcinoma may occur in a sporadic (s-medullary thyroid carcinoma, 75%) or in a multiple endocrine neoplasia type 2 form (MEN2, 25%). These clinical forms differ in many ways, as s-medullary thyroid carcinoma cases are RET-negative in the germline and are typically diagnosed later than medullary thyroid carcinoma in MEN2 patients. In this study, a set of cases with s-medullary thyroid carcinoma are documented and explored.

[Genetic screening of multiple endocrine neoplasia type 2: experience of the USP Endocrine Genetics Unit].

Multiple endocrine neoplasia type 2 (MEN-2) is an inherited tumor syndrome that includes medullary thyroid carcinoma (MTC), primary hyperparathyroidism, pheochromocytoma and other non-endocrine diseases. Since the first RET missense mutations in association with MEN-2 were identified, RET mutation analysis had a great impact in the clinical management of MEN-2, such as in early diagnosis and treatment of MTC. Presently, early total thyroidectomy provides real cure of MTC for cases in which molecular diagnosis has been performed at early ages.

A novel Val648Ile substitution in RET protooncogene observed in a Cys634Arg multiple endocrine neoplasia type 2A kindred presenting with an adrenocorticotropin-producing pheochromocytoma.

Multiple endocrine neoplasia type 2 (MEN 2) comprises a heterogeneous group of neoplasic disorders that most commonly have a single missense substitution of the RET protooncogene (RET) involving exons 10 and 11. It was previously reported a MEN 2A kindred in which the father presented with a rare phenotype consisting of bilateral ACTH-producing pheochromocytoma and medullary thyroid carcinoma. We recently performed mutational analysis of the father and his 4 children using a denaturing gradient gel electrophoresis approach and PCR-amplified genomic DNA, followed by direct sequencing or restriction fragment length polymorphism testing.

Familial growth hormone deficiency with mutated GHRH receptor gene: clinical and hormonal findings in homozygous and heterozygous individuals from Itabaianinha.

Objective: To characterize clinically and hormonally the syndrome of autosomal recessive familial growth hormone deficiency (FGHD) recently identified in Itabaianinha, Sergipe, Brazil, caused by a novel mutation (mt) that inactivates the growth hormone-releasing hormone receptor (GHRH-R) gene.

Design: Clinical and hormonal evaluations were performed in 21 FGHD individuals (mt/mt group) aged 8 to 63 years, 13 heterozygotes for the GHRH-R mutation (wt/mt group) and 5 homozygotes for the wild type (wt) allele (wt/wt group), identified by genotyping of peripheral blood leukocyte DNA.

Methods: Clinical and hormonal characterization included physical examination and measurement of GH, IGF-I, IGF binding protein-3 (IGFBP-3), cortisol, prolactin, LH, FSH, and free thyroxine (FT4).

A homozygous mutation in the luteinizing hormone receptor causes partial Leydig cell hypoplasia: correlation between receptor activity and phenotype.

Leydig cell hypoplasia (LCH) is characterized by a decreased response of the Leydig cells to LH. As a result, patients with this syndrome display aberrant male development ranging from complete pseudohermaphroditism to males with micropenis but with otherwise normal sex characteristics. We have evaluated three brothers with a mild form of LCH.