A thyroid nodule revealing a paraganglioma in a patient with a new germline mutation in the succinate dehydrogenase B gene.
A 32-year-old asymptomatic female was diagnosed with an isolated thyroid nodule of 2.5 cm diameter. Fine needle aspiration suggested a medullary thyroid carcinoma. Consequently, a total thyroidectomy was performed. The nodule stained positive for chromogranin A, neurone-specific enolase and synaptophysin, but not for calcitonin. Finally, pathological analysis showed a thyroid paraganglioma. Although the tumour appeared to be sporadic in a patient with no personal or familial history of paraganglioma and/or pheochromocytoma, we have identified a new mutation (392delC) of the succinate dehydrogenase-B (SDHB) gene in the genomic DNA extracted from the leukocytes of the patient. That mutation induced a shift in the reading frame of the gene creating a premature stop codon (P131fsX135) which was predicted to result in a truncated SDHB protein of 135 amino acids. This report highlights the difficulties of this unexpected diagnosis of hereditary thyroid paraganglioma. It also discusses the clinical involvements in terms of familial screening and the necessary follow-up of the patient.
Service des Maladies Endocriniennes et Metaboliques, Paris, France.
Baha
B
Zantour
Brigitte
B
Guilhaume
Frederique
F
Tissier
Albert
A
Louvel
Xavier
X
Jeunemaitre
Anne-Paule
AP
Gimenez-Roqueplo
Xavier
X
Bertagna
D000328:Adult; D004252:DNA Mutational Analysis; D005260:Female; D018095:Germ-Line Mutation; D006801:Humans; D007150:Immunohistochemistry; D007506:Iron-Sulfur Proteins; D010235:Paraganglioma / Q000235:genetics* / Q000473:pathology*; D021122:Protein Subunits / Q000235:genetics*; D013385:Succinate Dehydrogenase / Q000235:genetics*; D016606:Thyroid Nodule / Q000235:genetics* / Q000473:pathology*
D007506:Iron-Sulfur Proteins; D021122:Protein Subunits; C108095:SDHB protein, human; D013385:Succinate Dehydrogenase