RESUMEN
The description of the histological features and the immunohistochemical and molecular analyses of a case of cribriform-morular variant of papillary thyroid carcinoma in an 8-year-old girl with a family history of adenomatous polyposis is presented. The neoplasm was multifocal and bilateral, with a mixed pattern of solid, trabecular, and morular areas. The neoplasm showed angioinvasive behavior, extracapsular infiltration with extension to the perythyroidal muscles, and lymph node metastases. Tumor cells were positive for CAM 5.2, cytokeratins 5/6, TTF-1, HBME-1, galectin-3, and ß-catenin. In addition, the molecular tests did not reveal BRAF mutations, RET/PTC rearrangement, APC mutation, or KRAS mutation.
Asunto(s)
Carcinoma/patología , Análisis Mutacional de ADN , Inmunohistoquímica/métodos , Neoplasias de la Tiroides/patología , Biomarcadores/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma Papilar , Niño , ADN de Neoplasias/análisis , Proteínas de Unión al ADN/metabolismo , Supervivencia sin Enfermedad , Femenino , Galectina 3/metabolismo , Humanos , Queratinas/metabolismo , Disección del Cuello , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/metabolismo , Tiroidectomía , Factores de Transcripción , Resultado del Tratamiento , beta Catenina/metabolismoRESUMEN
OBJECTIVE: Iodide transport defect (ITD) is a rare disorder characterised by an inability of the thyroid to maintain an iodide gradient across the basolateral membrane of thyroid follicular cells, that often results in congenital hypothyroidism. When present the defect is also found in the salivary glands and gastric mucosa and it has been shown to arise from abnormalities of the sodium/iodide symporter (NIS). PATIENT: We describe a woman with hypothyroidism identified at the 3rd month of life. The diagnosis of ITD was suspected because of nodular goitre, and little if any iodide uptake by the thyroid and salivary glands. Treatment with iodide partially corrected the hypothyroidism; however, long-term substitution therapy with L-thyroxine was started. MEASUREMENTS: Thyroid radioiodide uptake was only 1.4% and 0.3% at 1 and 24 h after the administration of recombinant human TSH. The saliva to plasma I- ratio was 1.1 indicating that the inability of the thyroid gland to concentrate I- was also present in the salivary glands. RESULTS: Analysis of the patient's NIS gene revealed a 15 nucleotide (nt) deletion of the coding sequence (nt 1314 through nt 1328) and the insertion of 15 nt duplicating the first 15 nt of the adjacent intron. The patient was homozygous for this insertion/deletion, while both consanguineous parents were heterozygous. This deletion predicts the production of a protein lacking the five terminal amino acids of exon XI (439-443) which are located in the 6th intracellular loop. COS-7 cells transfected with a vector expressing the mutant del-(439-443) NIS failed to concentrate iodide, suggesting that the mutation was the direct cause of the ITD in this patient. CONCLUSION: In conclusion we describe the first Italian case of congenital hypothyroidism due to a new deletion in the NIS gene.
Asunto(s)
Hipotiroidismo Congénito , Eliminación de Gen , Simportadores/genética , Adulto , Animales , Células COS , Chlorocebus aethiops , Exones/genética , Familia , Femenino , Heterocigoto , Humanos , Hipotiroidismo/genética , Inmunohistoquímica/métodos , Intrones/genética , Yoduros/metabolismo , Glándula Tiroides/metabolismo , Glándula Tiroides/patología , TransfecciónRESUMEN
The aim of the study was to correlate the sonographic [ultrasound (US)] and color-Doppler (CFD) findings with the results of US-guided fine needle aspiration biopsy (FNA) and of pathologic staging of resected carcinomas to establish: 1) the relative importance of US features as risk factors of malignancy; and 2) a cost-effective management of nonpalpable thyroid nodules. Four hundred ninety-four consecutive patients with nonpalpable thyroid nodules (8-15 mm) were evaluated by US, CFD, and US-FNA. Ninety-two patients with inadequate cytology were excluded from the study. All patients with suspicious or malignant cytology underwent surgery, whereas subjects with benign cytology had clinical and US control 6 months later. Thyroid malignancies were observed in 18 of 195 (9.2%) solitary thyroid nodules and in 13 of 207 (6.3%) multinodular goiters. Cancer prevalence was similar in nodules greater or smaller than 10 mm (9.1 vs. 7.0%). Extracapsular growth (pT(4)) was present in 35.5%, and nodal involvement in 19.4% of neoplastic lesions, with no significant differences between tumors greater or smaller than 10 mm. At US cancers presented a solid hypoechoic appearance in 87% of cases, irregular or blurred margins in 77.4%, an intranodular vascular pattern in 74.2%, and microcalcifications in 29.0%. Irregular margins (RR 16.83), intranodular vascular spots (RR 14.29), and microcalcifications (RR 4.97) were independent risk factors of malignancy. FNA performed on hypoechoic nodules with at least one risk factor was able to identify 87% of the cancers at the expence of cytological evaluation of 38.4% of nonpalpable lesions. The majority of nonpalpable thyroid tumors can be identified by cytological evaluation of lesions presenting hypoechoic appearance in conjunction with one independent risk factor. Due to the nonnegligible prevalence of extracapsular growth and nodal metastasis, US-FNA should be performed on all 8-15 mm hypoechoic nodules with irregular margins, intranodular vascular spots or microcalcifications. Nonpalpable lesions of the thyroid without risk factors should be followed by means of clinical and US evaluation.