999 resultados para Thyroid tumor


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OBJECTIVE: Evaluate the efficacy of cumulative doses (CDs) of 131I-iodide therapy (RIT) in differentiated thyroid cancer (DTC). SUBJECTS AND METHODS: The probability of progressive disease according to CDs was evaluated in patients < 45 years old and > 45 years old and correlated to tumor-node-metastasis (TNM), thyroglobulin values, histological types and variants, age, and zduration of the disease. RESULTS: At the end of a follow-up period of 69 ± 56 months, 85 out of 150 DTC patients submitted to fixed doses RIT had no evidence of disease, 47 had stable disease and 18 had progressive disease. Higher CDs were used in the more aggressive variants (p < 0.0001), higher TNM stages (p < 0.0001), and follicular carcinomas (p = 0.0034). Probability of disease progression was higher with CDs > 600 mCi in patients > 45 years old and with CDs > 800 mCi in patients < 45 years. CONCLUSION: Although some patients may still respond to high CDs, the impact of further RIT should be carefully evaluated and other treatment strategies may be warranted.

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OBJECTIVE: To investigate the expression of SMAD proteins in human thyroid tissues since the inactivation of TGF-β/activin signaling components is reported in several types of cancer. Phosphorylated SMAD 2 and SMAD3 (pSMAD2/3) associated with the SMAD4 induce the signal transduction generated by TGF-β and activin, while SMAD7 inhibits this intracellular signaling. Although TGF-β and activin exert antiproliferative roles in thyroid follicular cells, thyroid tumors express high levels of these proteins. MATERIALS AND METHODS: The protein expression of SMADs was evaluated in multinodular goiter, follicular adenoma, papillary and follicular carcinomas by immunohistochemistry. RESULTS: The expression of pSMAD2/3, SMAD4 and SMAD7 was observed in both benign and malignant thyroid tumors. Although pSMAD2/3, SMAD4 and SMAD7 exhibited high cytoplasmic staining in carcinomas, the nuclear staining of pSMAD2/3 was not different between benign and malignant lesions. CONCLUSIONS: The finding of SMADs expression in thyroid cells and the presence of pSMAD2/3 and SMAD4 proteins in the nucleus of tumor cells indicates propagation of TGF-β/activin signaling. However, the high expression of the inhibitory SMAD7, mostly in malignant tumors, could contribute to the attenuation of the SMADs antiproliferative signaling in thyroid carcinomas.

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Background: The vascular endothelial growth factor (VEGF) is a major promoter of endothelial growth and migration. Some studies have shown a correlation between expression of this growth factor and prognosis in several cancers, including well-differentiated thyroid cancer. Aim: We studied VEGF expression, local invasiveness, and other prognostic factors in papillary thyroid carcinoma (PTC) to test the hypothesis that the expression of VEGF is correlated with the degree of invasion of PTC. Patients and Methods: Clinical and pathological data of 76 patients with PTC were retrospectively reviewed. Group 1 consisted of patients with gross locally invasive tumors, group 2 consisted of patients with only invasion of the thyroid capsule, and group 3 consisted of patients with noninvasive PTC. Results: VEGF expression was noted within the tumor in all groups of PTC patients but was absent in the surrounding normal tissue. Older patients had higher expression of VEGF than younger patients. The age of patients with strong reaction to VEGF was 46 +/- 14 (mean +/- standard deviation), and that in patients with a weaker reaction was 39 +/- 16 (p<0.05). Only 20% of patients with a follicular variant of PTC had a strong reaction to VEGF compared with 68% of patients with classical PTC (p<0.01). Conclusions: VEGF expression appears to be an early event in the development of PTC. Whether VEGF expression promotes the progression of PTC is not known, but the answer to this question may be important in view of its greater expression in older patients, a group whose prognosis in PTC is worse.

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Purpose: To identify papillary thyroid carcinoma (PTC)-associated transcripts, we compared the gene expression profiles of three Serial Analysis of Gene Expression libraries generated from thyroid tumors and a normal thyroid tissue. Experimental Design: Selected transcripts were validated in a panel of 57 thyroid tumors using quantitative PCR (qPCR). An independent set of 71 paraffin-embedded sections was used for validation using immunohistochemical analysis. To determine if PTC-associated gene expression could predict lymph node involvement, a separate cohort of 130 primary PTC (54 metastatic and 76 nonmetastatic) was investigated. The BRAF(V600E) mutational status was compared with qPCR data to identify genes that might be regulated by abnormal BRAF/MEK/extracellular signal-regulated kinase signaling. Results: We identified and validated new PTC-associated transcripts. Three genes (CST6, CXCL14, and DHRS3) are strongly associated with PTC. Immunohistochemical analysis of CXCL14 confirmed the qPCR data and showed protein expression in PTC epithelial cells. We also observed that CST6, CXCL14, DHRS3, and SPP1 were associated with PTC lymph node metastasis, with CST6, CXCL14, and SPP1 being positively correlated with metastasis and DHRS3 being negatively correlated. Finally, we found a strong correlation between CST6 and CXCL14 expression and BRAF(V600E) mutational status, suggesting that these genes may be induced subsequently to BRAF activation and therefore may be downstream in the BRAF/MEK/extracellular signal-regulated kinase signaling pathway. Conclusion: CST6, CXCL14, DHRS3, and SPP1 may play a role in PTC pathogenesis and progression and are possible molecular targets for FTC therapy.

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Background. Clinical and pathologic examinations cannot always provide a prognosis for patients with medullary thyroid carcinoma. Membrane type 1 matrix metalloproteinase (MT1-MMP) can act directly on carcinogenesis and takes part in 1 of the processes of metalloproteinase 2 activation, an enzyme related to prognostic impairment of patients with such tumor. Methods. Thirty-five patients who were submitted to surgery were followed up for an average of 74 months, Postoperative and final medical conditions were characterized for comparison with MT1-MMP immunostainings, performed in surgical paraffin blocks. A value of p < .05 was considered statistically significant. Results. Proposed index (association of proportion and intensity of immunostaining) and proportion of immunostained cells in primary specimens were correlated with cure or persistence after initial operations (p = .0216 and p = .0098, respectively). Conclusion. MT1-MMP immunostaining in primary tumor specimens is a new and complementary prognostic predictor in patients with medullary thyroid carcinomas. (C) 2009 Wiley Periodicals, Inc. Head Neck 32: 58-67, 2010

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Objectives: To develop an index for the ratio of metalloproteinase 2 (MMP-2) to its tissue inhibitor (TIMP-2) in immunostained medullary thyroid carcinoma specimens and to correlate it with clinical and pathologic prognostic factors. Metalloproteinases, enzymes related to the degradation of the extracellular matrix, take part in carcinogenesis and have been associated with the prognosis of neoplasias. Nevertheless, medullary carcinoma is rarely considered in research analysis. Researchers tend to favor the ratio of enzymes to their inhibitors over the absolute concentrations of these enzymes. Design: Retrospective study of surgical samples. Setting: Head and Neck Surgery and Endocrinology Departments, Universidade de Sao Paulo Medical School Hospital. Patients: Surgical specimens from 33 patients who had been observed for a mean of 76.8 months (range, 4-201 months) were immunohistochemically stained for MMP-2 and TIMP-2. Only patients whose clinical and pathologic data were complete and whose specimens were preserved were included in the study. Main Outcome Measures: The ratio between the expressions of MMP-2 and TIMP-2 was based on a staining index (immunostaining extent and intensity) of each of the markers. Results: Proportionally large expressions of TIMP-2 over MMP-2 correlated with low occurrences of positive findings on initial cervical examination for the presence of thyroid nodules and/or lymphadenopathy (P = .02) and cervical lymph node metastases (P < .001), conditions correlated with prognosis. A correlation with cure at the end of follow-up (P = .01) was also observed. (P < .05 was considered statistically significant.) Conclusion: The ratio of MMP-2 to TIMP-2 expression is an additional and novel prognostic predictor of the outcome of medullary carcinoma treated surgically.

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Objective To evaluate the morphologic findings most encountered in anaplastic thyroid carcinomas (ATCs) and evaluate for the expression of PAX-8. Study Design The cytology specimens from 21 cases of ATC were evaluated for the following several cytologic criteria, cell morphology, pleomorphism, presence or absence of multinucleated cells, neutrophilic infiltrate and well-differentiated component. Immunohistochemical studies for PAX-8 were performed on cell blocks in selected cases. Results The most common morphology present was epithelioid, followed by spindle, multinucleated giant cell and rhabdoid, with 75% demonstrating more than 1 cell morphology. Marked pleomorphism (81%), neutrophilic infiltrate (90%) and necrosis (63%) were frequent. No nuclear grooves, colloid or well-differentiated component was idenrifled in any case. Immunocytochemical stains for PAX-8 were negative in 5 cases in which a cell block was available. Conclusion ATC is a tumor with diverse morphologic characteristics, and more than 1 cell morphology is usually present A neutrophilic infiltrate is a common finding and represents a clue to the correct diagnosis. (Acta Cytol 2010;54:668-672)

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Thyroid cancer is the most frequent endocrine neoplasia worldwide. The route for metastasis and loco-regional invasion preferentially occurs by lymphatic vessels. For this reason, the assessment of lymphatic vessel density (LVD) is supposed to represent both a prognostic parameter and also a potential therapeutic target. In order to evaluate the value of LVD in benign and malignant thyroid lesions, we analyzed 110 thyroidectomy specimens using D2-40, a specific marker for lymphatic vessels and vascular endothelial growth factor C (VEGF-C), the most potent molecule of lymphatic proliferation. LVD was significantly different between papillary and follicular carcinomas in total (p = 0.045) and peritumoral area (p = 0.042). Follicular adenoma and follicular carcinoma showed an important difference of intra- (p = 0.019) and peritumoral (p = 0.033) LVD. VEGF-C was more markedly expressed in malignancies than in benignant lesions (p = 0.0001). Almost all cancers with high positive VEGF-C expression also exhibited increased peritumoral LVD (p = 0.049) when compared with the benignant lesions. Indeed, the high peritumoral LVD of malignant thyroid lesions is an important finding for surgery planning and supports the practice of total thyroidectomy in malignant thyroid neoplasm`s since the lymphatic peritumoral vessels definitely are an escape path for tumor cells.

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Context: Telomerase promoter mutations (TERT) were recently described in follicular cell-derived thyroid carcinomas (FCDTC) and seem to be more prevalent in aggressive cancers. Objectives: We aimed to evaluate the frequency of TERT promoter mutations in thyroid lesions and to investigate the prognostic significance of such mutations in a large cohort of patients with differentiated thyroid carcinomas (DTCs). Design: This was a retrospective observational study. Setting and Patients: We studied 647 tumors and tumor-like lesions. A total of 469 patients with FCDTC treated and followed in five university hospitals were included. Mean follow-up (±SD) was 7.8 ± 5.8 years. Main Outcome Measures: Predictive value of TERT promoter mutations for distant metastasization, disease persistence at the end of follow-up, and disease-specific mortality. Results: TERT promoter mutations were found in 7.5% of papillary carcinomas (PTCs), 17.1% of follicular carcinomas, 29.0% of poorly differentiated carcinomas, and 33.3% of anaplastic thyroid carcinomas. Patients with TERT-mutated tumors were older (P < .001) and had larger tumors (P = .002). In DTCs, TERT promoter mutations were significantly associated with distant metastases (P < .001) and higher stage (P < .001). Patients with DTC harboring TERT promoter mutations were submitted to more radioiodine treatments (P = .009) with higher cumulative dose (P = .004) and to more treatment modalities (P = .001). At the end of follow-up, patients with TERT-mutated DTCs were more prone to have persistent disease (P = .001). TERT promoter mutations were significantly associated with disease-specific mortality [in the whole FCDTC (P < .001)] in DTCs (P < .001), PTCs (P = .001), and follicular carcinomas (P < .001). After adjusting for age at diagnosis and gender, the hazard ratio was 10.35 (95% confidence interval 2.01–53.24; P = .005) in DTC and 23.81 (95% confidence interval 1.36–415.76; P = .03) in PTCs. Conclusions: TERT promoter mutations are an indicator of clinically aggressive tumors, being correlated with worse outcome and disease-specific mortality in DTC. TERT promoter mutations have an independent prognostic value in DTC and, notably, in PTC.

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Struma ovarii is an infrequent ovarian tumor, and there are only few reports with detailed data of thyroid function. In several cases, malignant struma ovarii have been shown to produce hyperthyroidism, but there is no reported case of hypothyroidism following struma ovarii tumor resection. A 62-year-old white woman underwent right ovary resection that had a pathologic diagnosis of struma ovarii. After 6 days, she developed weakness, myalgia, somnolence, nausea, and arterial hypotension. Laboratory tests showed a high level of thyroid-stimulating hormone (TSH) and a decreased level thyroxin. Thyroxin replacement therapy was initiated, and the patient became completely asymptomatic. This is the first reported case of a previously asymptomatic woman who developed a definite clinical hypothyroidism after resection of a struma ovarii tumor.

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The preparation of a novel radioiodination reagent, the (aminooxy)acetyl derivative of (p-[125]-iodophenyl)ethylamine, is described. Conventional radioiodination of proteins involves the formation of iodotyrosine residues, but for in vivo applications such as thyroid or stomach immunoscintigraphy, the susceptibility of these residues to tissue dehalogenases constitutes a serious disadvantage. Using our new compound, which has a particularly nonreactive aromatic ring, we confirm and extend studies published by other workers indicating the much greater in vivo stability of iodophenyl compounds compared to the more conventional iodophenolic ones. In addition, the aminooxy group of our reagent gives a stable and specific linkage to aldehyde groups formed by periodate oxidation on the sugar moiety of antibody molecules. In vitro, favorable binding activity and high stability was obtained with a (([125I]iodoaryl)amino)oxy labeled monoclonal antibody directed against carcinoembryonic antigen. In vivo, using paired labeling experiments in nude mice bearing colon carcinoma xenografts, the (([125I]iodoaryl)amino)oxy-MAb (MAb = monoclonal antibody) was compared with the same MAb 131I-labeled by conventional chloramine-T method. Tumor 125I concentration of (arylamino)oxy MAb (measured as percent injected dose per gram) was significantly higher as compared to values obtained with a conventionally labeled 131I antibody. Additionally, thyroid uptake, an indicator of iodine release from the antibody, was up to 25 times lower after injection of 125I-MAb obtained by the new method as compared to the conventionally iodinated 131I-MAb.

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Segons resultats de fases II amb inhibidors tirosina quinasa i el coneixement de les alteracions moleculars de la carcinogènesis tiroïdal, es va dissenyar un estudi retrospectiu de pacients amb càncer de tiroide metastàtic tractats amb sorafenib. S’analitzaren la taxa de respostes, toxicitat, supervivència i la correlació amb els marcadors tumorals de 34 pacients. Segons subtipus histològic, la taxa de respostes va ser 47% en medul•lars, 19% en diferenciats i 33% en anaplàsics. La mitjana de supervivència-lliure-de-progressió va ser 13.5, 10.5 i 4.4 mesos, respectivament. Es va observar correlació significativa entre la reducció dels nivells de marcador tumoral i la resposta. El perfil de toxicitat va ser favorable.

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INTRODUCTION Metastatic tumors account for 1.4-2.5% of thyroid malignancies. About 25-30% of patients with clear cell renal carcinoma (CCRC) have distant metastasis at the time of diagnosis, being the thyroid gland a rare localization [5%]. PRESENTATION OF THE CASE A 62-year woman who underwent a cervical ultrasonography and a PAAF biopsy reporting atypical follicular proliferation with a few intranuclear vacuoles "suggestive" of thyroid papillary cancer in the context of a multinodular goiter was reported. A total thyroidectomy was performed and the histology of a clear cell renal carcinoma (CCRC) was described in four nodules of the thyroid gland. A CT scan was performed and a renal giant right tumor was found. The patient underwent an eventful radical right nephrectomy and the diagnosis of CCRC was confirmed. DISCUSSION Thyroid metastasis (TM) from CCRC are usually apparent in a metachronic context during the follow-up of a treated primary (even many years after) but may sometimes be present at the same time than the primary renal tumor. Our case is exceptional because the TM was the first evidence of the CCRC, which was subsequently diagnosed and treated. CONCLUSION The possibility of finding of an incidental metastatic tumor in the thyroid gland from a previous unknown and non-diganosed primary (as CCRC in our case was) is rare and account only for less than 1% of malignancies. Nonetheless, the thyroid gland is a frequent site of metastasis and the presence of "de novo" thyroid nodules in oncologic patients must be always considered and studied.

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Members of the tumor necrosis factor (TNF) family induce pleiotropic biological responses, including cell growth, differentiation, and even death. Here we describe a novel member of the TNF family designated APRIL (for a proliferation-inducing ligand). Although transcripts of APRIL are of low abundance in normal tissues, high levels of mRNA are detected in transformed cell lines, and in human cancers of colon, thyroid, and lymphoid tissues in vivo. The addition of recombinant APRIL to various tumor cells stimulates their proliferation. Moreover, APRIL-transfected NIH-3T3 cells show an increased rate of tumor growth in nude mice compared with the parental cell line. These findings suggest that APRIL may be implicated in the regulation of tumor cell growth.

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BACKGROUND: Mixed medullary-follicular thyroid carcinoma denotes a rare and heterogeneous group of tumors displaying morphological and immunophenotypical features of both origins within the same lesion. METHOD: We report a case of a 41-year-old woman with a lump in the right side of the neck, increasing in pain and size over several weeks. Serum levels of calcitonine (1140 ng/L) and carcinoembryonic antigen (288 microg/L) were very high. Fine-needle aspiration cytology suggested a diagnosis of medullary thyroid carcinoma. Total thyroidectomy, along with bilateral functional neck and mediastinal lymph-node dissection, were performed. RESULTS: The histopathological examination yielded a diagnosis of medullary carcinoma in the right thyroid lobe, closely intermingled with a nonencapsulated classical papillary carcinoma. One ipsilateral lymph node showed micrometastasis of the medullary counterpart. CONCLUSION: When compared with other cases reported in literature, this particular presentation should be recognized, if required, morphologic and functional criteria are used. The treatment is mostly surgical, driven by the medullary component. The presence of micrometastasis in 1 ipsilateral cervical lymph-node underlines the importance of cervicomediastinal lymph-node dissection and careful searching for metastatic disease.