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Sentinel lymph node (SLN) mapping is a standard, minimally-invasive diagnostic method in the surgical treatment of many solid tumors, as for example melanoma and breast cancer, for detecting the presence of regional nodal metastases. A negative SLN accurately indicates the absence of metastases in the other regional lymph nodes (LN), thus avoiding unnecessary lymph nodal dissection. Papillary thyroid carcinoma (PTC) is the most common type of thyroid carcinoma (TC) with cervical LN metastases at diagnosis in 20-90%, and nodal involvement correlates with local persistence/recurrence. The SLN in PTC is an intraoperative method for staging preoperative N0 patients and for detecting metastatic LNs "in and outside" the cervical LN central compartment; it represents an alternative method to prophylactic central neck node dissection. In this review we summarize different methods and results of the use of SLN in TC. The SLN identification techniques currently used include the selective vital-dye (VD) method, 99mTc-nanocolloid planar lymphoscintigraphy with intraoperative use of a hand-held gamma probe (LS), the combination LS + VD, and the combination LS and preoperative SPECT-CT (LS + SPECT/CT). The application of the SLN procedure in TC has been described in many studies, however, the techniques are heterogeneous, and the role of SLN in TC, with indications, results, advantages and limits, is still debated.
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INTRODUCTION: Medullary thyroid carcinoma (MTC) constitutes approximately 5-10% of all thyroid cancers. Although the tumor forms in the thyroid, it doesn't originate from thyroid cells, but from the C cells or parafollicular cells which produce and release a hormone called calcitonin (CT). Starting from the second half of the 1900s, MTC was progressively studied and defined. AREAS COVERED: This study aims to analyze the history, clinical presentation and biological behavior of MTC, bio-humoral and instrumental diagnosis, molecular profiling, genetic screening, preoperative staging and instrumental procedures, indispensable in expert and dedicated hands, such as high-resolution ultrasonography, CT-scan, MRI and PET/TC. We examine recommended and controversial surgical indications and procedures, prophylactic early surgery and multiple endocrine neoplasia surgery. Also, we discuss pathological anatomy classification and targeted therapies. The role of serum CT is valued both as undisputed and constant preoperative diagnostic marker, obscuring cytology and as early postoperative marker that predicts disease persistence. EXPERT OPINION: With a complete preoperative study, unnecessary or useless, late and extended interventions can be reduced in favor of tailored surgery that also considers quality of life. Finally, great progress has been made in targeted therapy, with favorable impact on survival.
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Carcinoma Medular , Neoplasias da Glândula Tireoide , Humanos , Carcinoma Medular/genética , Carcinoma Medular/patologia , Carcinoma Medular/cirurgia , Qualidade de Vida , Tireoidectomia , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/terapiaRESUMO
BACKGROUND: Medullary thyroid cancer (MTC) accounts for 5% of all thyroid cancers and occurs either sporadically or in a hereditary pattern. Routine calcitonin (CT) measurement is suggested for MTC screening in patients with nodular thyroid disease. PATIENT FINDINGS: A 45 years-old woman incidentally discovered, with neck ultrasound, the presence of thyroid micronodules. Fine-needle aspiration (FNA) on thyroid prevailing nodule did not demonstrate cellular atypia. During follow-up, FNA was repeated on the previously analyzed nodule suspicious for Hürthle cell nodule suspicious for follicular neoplasm and on another hypoechoic right nodule which showed cellular atypia. CT was <2 pg/ml (normal values <18.2 pg/ml), anti-thyroid antibodies were positive and the patient showed a normal thyroid function. The patient also was diagnosed with primary hyperparathyroidism with an enlarged parathyroid gland behind the right thyroid lobe. Therefore, she underwent total thyroidectomy and a selective parathyroidectomy was performed. Histology showed an encapsulated microMTC (pT1aNxMx) associated with diffuse C-cell hyperplasia and lymphocytic thyroiditis. The neoplasm was positive for calcitonin and chromogranin A and negative for thyroglobulin. A right parathyroid adenoma was also diagnosed. One month after surgery basal and stimulated CT were <2 ng/ml. Genetic analysis did not reveal mutation of RET proto-oncogene. Twelve months after surgery, neck ultrasonography, chest and abdomen computed tomography did not demonstrated residual/recurrent disease with undetectable serum CT. CONCLUSION: In the literature, few MTC cases with normal serum CT have been reported. Although MTC without elevated plasma CT is extremely rare, normal or low CT levels, do not entirely exclude this diagnosis.
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Carcinoma Neuroendócrino/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Biópsia por Agulha Fina , Carcinoma Neuroendócrino/complicações , Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Achados Incidentais , Pessoa de Meia-Idade , Proto-Oncogene Mas , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/complicações , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/complicações , Nódulo da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/patologia , TireoidectomiaRESUMO
PURPOSE: To assess the role of clinical, biochemical, and morphological parameters, as added to cytology, for improving pre-surgical diagnosis of palpable thyroid nodules. METHODS: Patients with a palpable thyroid nodule were eligible if surgical intervention was indicated after a positive or suspicious for malignancy FNAC (TIR 4-5 according to the 2007 Italian SIAPEC-IAP classification), or two inconclusive FNAC at a ≥3 months interval, or a negative FNAC associated with one or more risk factor. Reference standard was histological malignancy diagnosis. Likelihood ratios of malignancy, sensitivity, specificity, negative (NPV), and positive predictive value (PPV) were described. Multiple correspondence analysis (MCA) and logistic regression were applied. RESULTS: Cancer was found in 433/902 (48%) patients. Considering TIR4-5 only as positive cytology, specificity, and PPV were high (94 and 91%) but sensitivity and NPV were low (61 and 72%); conversely, including TIR3 among positive, sensitivity and NPV were higher (88 and 82%) while specificity and PPV decreased (52 and 63%). Ultrasonographic size ≥3 cm was independently associated with benignity among TIR2 cases (OR of malignancy 0.37, 95% CI 0.18-0.78). In TIR3 cases the hard consistency of small nodules was associated with malignity (OR: 3.51, 95% CI 1.84-6.70, p < 0.001), while size alone, irrespective of consistency, was not diagnostically informative. No other significant association was found in TIR2 and TIR3. CONCLUSIONS: The combination of cytology with clinical and ultrasonographic parameters may improve diagnostic definition of palpable thyroid nodules. However, the need for innovative diagnostic tools is still high.
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Nódulo da Glândula Tireoide/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biópsia por Agulha Fina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Palpação , Valor Preditivo dos Testes , Estudos Prospectivos , Nódulo da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/cirurgia , Ultrassonografia , Adulto JovemRESUMO
INTRODUCTION: Primary paraganglioma (PG) of the thyroid gland is an extremely rare neuroendocrine tumor with potential for misdiagnosis. We describe 2 cases of thyroid PG, suggest a possible diagnostic and therapeutic management strategy, and present a systematic review of the literature. CASE REPORTS: Two 67-year-old women presented similarly with asymptomatic but rapidly growing thyroid nodules in which malignancy was suspected after fine needle aspiration biopsy, "THY 4" according to the 2014 SIAPEC classification, both undergoing total thyroidectomy. Unexpectedly, immunohistochemistry showed neuroendocrine cellular architecture that was negative for common markers of well-differentiated follicular neoplasms, thyroglobulin, thyroid transcription factor 1, cytokeratins and medullary thyroid cancer, calcitonin, carcinoembryonic antigen, whereas neuron-specific enolase, synaptophysin, chromogranin A, and S-100 protein were highly expressed, confirming the diagnosis of primary thyroid PG. The patients were both discharged on postoperative day 2, without any other therapy and are currently well without evidence of local recurrence of metastatic disease, after 4 years and 3 months of follow-up, respectively. DISCUSSION: These are the only 2 cases of thyroid PG experienced in our center which specializes in thyroid surgery. Thyroid PG is a rare neuroendocrine neoplasm first described by Van Miert in 1964 with just over 50 cases reported in the literature. Our experience is concordant with the literature that the diagnosis of the primary PG of the thyroid is challenging, due to its low prevalence and the cytologic and histopathologic similarities with other more frequently diagnosed benign and malignant thyroid tumors. Immunohistochemistry is required for definitive diagnosis but gross tumor characteristics are also helpful for diagnosis. Surgical resection is the recommended standard treatment.
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Paraganglioma/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Idoso , Gerenciamento Clínico , Feminino , Humanos , Paraganglioma/diagnóstico , Prognóstico , Neoplasias da Glândula Tireoide/diagnósticoRESUMO
OBJECTIVE: Sporadic carcinoma of the parathyroid glands is a rare malignant neoplasia. The GCM2 gene encodes a transcription factor that is crucial to embryonic parathyroid development. The Y282D variant of GCM2 exhibits increased transcriptional activity, and the presence of this variant is significantly associated with a higher prevalence of primitive hyperparathyroidism. The present study investigated the prevalence of the Y282D variant of the GCM2 gene and its association with clinical parameters in patients with a definitive histological diagnosis of sporadic parathyroid carcinoma (SPC) or atypical adenoma (AA).
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Carcinogênese/genética , Proteínas Nucleares/genética , Neoplasias das Paratireoides/genética , Polimorfismo de Nucleotídeo Único/genética , Fatores de Transcrição/genética , Sequência de Bases , Carcinogênese/patologia , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The "non-recurrent" course of the inferior laryngeal nerve (ILN) is an anatomical variant which must be borne in mind during thyroid surgery. The "non-recurrent" course of the ILN on the right side is associated with the aberrant right subclavian artery (arteria lusoria), and, on the left, is described in situs viscerum inversus. We present a case in which the "arteria lusoria" was not associated with the non-recurrent right ILN. The aims of this paper are to report this "anomaly of the anomaly" to surgeons who may be unaware of it on the one hand and on the other to emphasize that this is the only case so far reported in the literature. Moreover we proposed to explain embryologically these unexpected findings.
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Aneurisma/diagnóstico por imagem , Anormalidades Cardiovasculares/diagnóstico por imagem , Nervo Laríngeo Recorrente/anormalidades , Artéria Subclávia/anormalidades , Tomografia Computadorizada por Raios X , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Esvaziamento Cervical , Artéria Subclávia/diagnóstico por imagem , Neoplasias da Glândula Tireoide/cirurgia , TireoidectomiaRESUMO
The most appropriate surgical management of "follicular neoplasm/suspicious for follicular neoplasm" lesions (FN), considering their low definitive malignancy rate and the limited predictive power of preoperative clinic-diagnostic factors, is still controversial. On behalf of the Italian Association of Endocrine Surgery Units (U.E.C. CLUB), we collected and analyzed the experience of 26 endocrine centers by computerized questionnaire. 1379 patients, surgically treated after a FN diagnosis from January 2012 and December 2103, were evaluated. Histological features, surgical complications, and medium-term outcomes were reported. Total thyroidectomy (TT) was performed in 1055/1379 patients (76.5 %), while hemithyroidectomy (HT) was carried out in 324/1379 cases (23.5 %). Malignancy rate was higher in TT than in HT groups (36.4 vs. 26.2 %), whereas the rates of transient and definitive hypoparathyroidism following TT were higher than after HT. Consensual thyroiditis (16.8 vs. 9.9 %) and patient age (50.9 vs. 47.9 %) also differed between groups. A cytological FN diagnosis was associated to a not negligible malignancy rate (469/1379 patients; 34 %), that was higher in TT than in HT groups. However, a lower morbidity rate was observed in HT, which should be considered the standard of care in solitary lesions in absence of specific risk factors. Malignancy could not be preoperatively assessed and clinical decision-making is still controversial. Further efforts should be spent to more accurately preoperatively classify FN thyroid nodules.
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Adenocarcinoma Folicular/cirurgia , Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/métodos , Adenocarcinoma Folicular/patologia , Adulto , Idoso , Feminino , Humanos , Hipoparatireoidismo/etiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Risco , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Tireoidectomia/efeitos adversos , Resultado do TratamentoRESUMO
Gender influences Papillary Thyroid Cancer (PTC) with an incidence of 3:1 when comparing women to men with different aggressiveness. This gender discrepancy suggests some role of sex hormones in favoring the malignant progression of thyroid tissue to cancer. Estrogens are known to promote Stem Cell self-renewal and, therefore, may be involved in tumor initiation. The goals of these studies are to investigate the underlying causes of gender differences in PTC by studying the specific role of estrogens on tumor cells and their involvement within the Cancer Stem Cell (CSC) compartment. Exposure to 1nmoll-1 Estradiol for 24h promotes growth and maintenance of PTC Stem Cells, while inducing dose-dependent cellular proliferation and differentiation following Estradiol administration. Whereas mimicking a condition of hormonal imbalance led to an opposite phenotype compared to a continuous treatment. In vivo we find that Estradiol promotes motility and tumorigenicity of CSCs. Estradiol-treated mice inoculated with Thyroid Cancer Stem Cell-enriched cells developed larger tumor masses than control mice. Furthermore, Estradiol-pretreated Cancer Stem cells migrated to distant organs, while untreated cells remained circumscribed. We also find that the biological response elicited by estrogens on Papillary Thyroid Cancer in women differed from men in pathways mediated. This could explain the gender imbalance in tumor incidence and development and could be useful to develop gender specific treatment of (PTC).
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Estrogênios/farmacologia , Células-Tronco/fisiologia , Neoplasias da Glândula Tireoide/metabolismo , Adulto , Animais , Biomarcadores , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Esquema de Medicação , Estrogênios/administração & dosagem , Estrogênios/metabolismo , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neoplasias Experimentais , Caracteres Sexuais , Células-Tronco/efeitos dos fármacosRESUMO
BACKGROUND: Risk stratification in patients with papillary thyroid carcinoma (PTC) currently relies on postoperative parameters. Testing for BRAF mutations preoperatively may serve as a novel tool for identifying PTC patients at risk of persistence/recurrence after surgery. METHODS: The study involved 185 consecutive patients with a histological diagnosis of PTC and BRAF analysis performed on thyroid fine-needle aspiration biopsy (FNAB). We assessed BRAF status in FNAB specimens obtained before thyroidectomy for PTC, and examined its association with the clinicopathological characteristics identified postoperatively, and with outcome after a mean 55±15 months of follow-up. RESULTS: One hundred and fifteen of 185 (62%) PTCs carried a BRAF mutation. Univariate analysis showed that BRAF status correlated with the histological variant of PTC, cancer size, and stage at diagnosis, but not with gender, age, multifocality, or lymph node involvement. BRAF-mutated cases had a higher prevalence of persistent/recurrent disease by the end of the follow-up (11% vs. 8%), but this difference was not statistically significant. The Kaplan-Meier curve shows that among the patients with persistent/recurrent disease, BRAF-mutated patients needed a second treatment earlier than patients with BRAF wild-type, although the difference did not completely reach the statistical significance. CONCLUSIONS: Our study confirmed that preoperatively-identified BRAF mutation are associated with certain pathological features of PTC that correlate with prognosis. We speculate that it has a role in identifying PTCs that would generally be considered low-risk but that may reveal an aggressive behavior during their follow-up.
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Carcinoma/diagnóstico , Carcinoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética , Tireoidectomia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina , Carcinoma/patologia , Carcinoma/cirurgia , Carcinoma Papilar , Análise Mutacional de DNA , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Adulto JovemRESUMO
Medullary thyroid cancer (MTC) is an aggressive malignancy responsible for up to 14% of all thyroid cancer-related deaths. It is characterized by point mutations in the rearranged during transfection (RET) proto-oncogene. The activated RET kinase is known to signal via extracellular signal regulated kinase (ERK) and phosphoinositide 3-kinase (PI3K), leading to enhanced proliferation and resistance to apoptosis. In the present work, we have investigated the effect of two serine/threonine-protein kinase B-Raf (BRAF) inhibitors (RAF265 and SB590885), and a PI3K inhibitor (ZSTK474), on RET-mediated signalling and proliferation in a MTC cell line (TT cells) harbouring the RETC634W activating mutation. The effects of the inhibitors on VEGFR2, PI3K/Akt and mitogen-activated protein kinases signalling pathways, cell cycle, apoptosis and calcitonin production were also investigated. Only the RAF265+ ZSTK474 combination synergistically reduced the viability of treated cells. We observed a strong decrease in phosphorylated VEGFR2 for RAF265+ ZSTK474 and a signal reduction in activated Akt for ZSTK474. The activated ERK signal also decreased after RAF265 and RAF265+ ZSTK474 treatments. Alone and in combination with ZSTK474, RAF265 induced a sustained increase in necrosis. Only RAF265, alone and combined with ZSTK474, prompted a significant drop in calcitonin production. Combination therapy using RAF265 and ZSTK47 proved effective in MTC, demonstrating a cytotoxic effect. As the two inhibitors have been successfully tested individually in clinical trials on other human cancers, our preclinical data support the feasibility of their combined use in aggressive MTC.
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Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Neuroendócrino/tratamento farmacológico , Imidazóis/uso terapêutico , Piridinas/uso terapêutico , Neoplasias da Glândula Tireoide/tratamento farmacológico , Triazinas/uso terapêutico , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Calcitonina/genética , Calcitonina/metabolismo , Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imidazóis/farmacologia , Concentração Inibidora 50 , Modelos Biológicos , Proto-Oncogene Mas , Piridinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Triazinas/farmacologiaRESUMO
There is considerable variability in the surgical approach to differentiated thyroid cancer regarding the decision to explore and remove central or central and lateral compartment lymph nodes. Much as sentinel lymph node sampling has improved the decision to remove axillary nodes for breast cancer, vital dye and lymphoscintigraphy with lymph node sampling may direct the surgical approach to differentiated thyroid cancer.
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Carcinoma/diagnóstico por imagem , Linfocintigrafia/métodos , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Carcinoma/patologia , Carcinoma/cirurgia , Carcinoma Papilar , Humanos , Metástase Linfática , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgiaRESUMO
The truncated somatostatin receptor variant sst5TMD4 associates with increased invasiveness and aggressiveness in breast cancer. We previously found that sst5 activation may counteract sst2 selective agonist effects in a medullary thyroid carcinoma (MTC) cell line, the TT cells, and that sst5TMD4 is overexpressed in poorly differentiated thyroid cancers. The purpose of this study is to evaluate sst5TMD4 expression in a series of human MTC and to explore the functional role of sst5TMD4 in TT cells. We evaluated sst5TMD4 and sst5 expression in 36 MTC samples. Moreover, we investigated the role of sst5TMD4 in TT cells evaluating cell number, DNA synthesis, free cytosolic calcium concentration ([Ca(2+)]i), calcitonin and vascular endothelial growth factor levels, cell morphology, protein expression, and invasion. We found that in MTC the balance between sst5TMD4 and sst5 expression influences disease stage. sst5TMD4 overexpression in TT cells confers a greater growth capacity, blocks sst2 agonist-induced antiproliferative effects, modifies the cell phenotype, decreases E-cadherin and phosphorylated ß-catenin levels, increases vimentin, total ß-catenin and phosphorylated GSK3B levels (in keeping with the development of epithelial to mesenchymal transition), and confers a greater invasion capacity. This is the first evidence indicating that sst5TMD4 is expressed in human MTC cells, where it associates with more aggressive behavior, suggesting that sst5TMD4 might play a functionally relevant role.
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Carcinoma Neuroendócrino/metabolismo , Receptores de Somatostatina/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Adolescente , Adulto , Idoso , Carcinoma Neuroendócrino/patologia , Linhagem Celular Tumoral , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Isoformas de Proteínas , Neoplasias da Glândula Tireoide/patologia , Adulto JovemRESUMO
Programmed cell death 4 (PDCD4) is a tumor suppressor gene involved in tumorogenesis. MicroRNA-21 (miR-21) specifically targets PDCD4, and recent studies suggest that PDCD4 is also regulated by Akt (antiapoptotic regulator within phosphatidylinositol 3-kinase). Medullary thyroid carcinoma (MTC) is a rare neuroendocrine cancer, and disease stage at diagnosis represents the main prognostic indicator. A consecutive series of 64 MTCs was considered. REarranged during Transfection (RET) and rat sarcoma (RAS) mutation status was assessed by direct sequencing. Quantitative real-time polymerase chain reaction was used to quantify mature hsa-miR-21. PDCD4 and Ki-67 immunostaining was performed with an automated platform. Immunoblot analysis of PI3K/Akt pathway was done on thyroid tissues. MTCs were consistently associated with miR-21 up-regulation (P < .0016) and featured significant PDCD4 nuclear down-regulation. An inverse correlation emerged between miR-21 overexpression and PDCD4 down-regulation (P = .0013). At enrollment, high miR-21 levels were associated with high calcitonin levels (P = .0003), lymph node metastases (P = .001), and advanced stages (P = .0003). At the end of follow-up, high miR-21 levels were associated with biochemically persistent disease (P = .0076). At enrollment, instead, PDCD4 nuclear down-regulation was associated with high calcitonin levels (P = .04), more advanced stages of disease (P < .01), and persistent disease after the follow-up (P = .02). p-Akt was more expressed in RAS-mutated MTC than in nonmutated cancers and normal tissue. This study showed, in MTCs, that miR-21 regulates PDCD4 expression and also that the miR-21/PDCD4 pathway correlates with clinicopathological variables and prognosis. Further studies should investigate the role of miR-21 as a prognostic biomarker and the feasibility of using PDCD4-restoring strategies as a therapeutic approach to MTC.
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Proteínas Reguladoras de Apoptose/análise , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , MicroRNAs/genética , Proteínas de Ligação a RNA/análise , Transdução de Sinais , Neoplasias da Glândula Tireoide/química , Neoplasias da Glândula Tireoide/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Biópsia , Calcitonina/sangue , Carcinoma Neuroendócrino , Criança , Pré-Escolar , Análise Mutacional de DNA , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Antígeno Ki-67/análise , Masculino , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Fenótipo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/análise , Proteínas Proto-Oncogênicas c-ret/genética , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/mortalidade , Neoplasias da Glândula Tireoide/patologia , Regulação para Cima , Adulto Jovem , Proteínas ras/genéticaRESUMO
Recent discoveries highlight the emerging role of estrogens in the initiation and progression of different malignancies through their interaction with stem cell (SC) compartment. Estrogens play a relevant role especially for those tumors bearing a gender disparity in incidence and aggressiveness, as occurs for most thyroid diseases. Although several experimental lines suggest that estrogens promote thyroid cell proliferation and invasion, their precise contribution in SC compartment still remains unclear. This review underlines the interplay between hormones and thyroid function, which could help to complete the puzzle of gender discrepancy in thyroid malignancies. Defining the association between estrogen receptors' status and signaling pathways by which estrogens exert their effects on thyroid cells is a potential tool that provides important insights in pathogenetic mechanisms of thyroid tumors.
RESUMO
AIM: Acromegaly reportedly carries an increased risk of malignant and benign thyroid tumors, with a prevalence of thyroid cancer of around 3-7%. Germline mutations in the aryl-hydrocarbon receptor (AHR) interacting protein (AIP) have been identified in familial forms of acromegaly. The molecular and endocrine relationships between follicular thyroid growth and GH-secreting pituitary adenoma have yet to be fully established. Our aim was to study the prevalence of differentiated thyroid cancer (DTC) in acromegaly, focusing on the role of genetic events responsible for the onset of thyroid cancer. METHODS: Germline mutations in the AIP gene were assessed in all patients; BRAF and H-N-K RAS status was analyzed by direct sequencing in thyroid specimens, while immunohistochemistry was used to analyze the protein expression of AIP and AHR. A set of PTCs unrelated to acromegaly was also studied. RESULTS: 12 DTCs (10 papillary and 2 follicular carcinomas) were identified in a cohort of 113 acromegalic patients. No differences in GH/IGF-1 levels or disease activity emerged between patients with and without DTC, but the former were older and more often female. BRAF V600E was found in 70% of the papillary thyroid cancers; there were no RAS mutations. AIP protein expression was similar in neoplastic and normal cells, while AHR protein was expressed more in PTCs carrying BRAF mutations than in normal tissue, irrespective of acromegaly status. CONCLUSIONS: The prevalence of DTC in acromegaly is around 11% and endocrinologists should bear this in mind, especially when examining elderly female patients with uninodular goiter. The DTC risk does not seem to correlate with GH/IGF-1 levels, while it may be associated with BRAF mutations and AHR over-expression. Genetic or epigenetic events probably play a part in promoting thyroid carcinoma.
Assuntos
Acromegalia/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carcinoma/genética , Receptores de Hidrocarboneto Arílico/genética , Neoplasias da Glândula Tireoide/genética , Regulação para Cima , Acromegalia/complicações , Acromegalia/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinoma/etiologia , Carcinoma/metabolismo , Carcinoma Papilar , Feminino , Seguimentos , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Proteínas Proto-Oncogênicas B-raf/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/etiologia , Neoplasias da Glândula Tireoide/metabolismo , Adulto JovemRESUMO
Sporadic medullary thyroid carcinoma (MTC) harbors RET gene somatic mutations in up to 50 % of cases, and RAS family gene mutations occur in about 10 %. A timely and comprehensive characterization of molecular alterations is needed to improve MTC diagnostic stratification and design-tailored therapeutic approaches. Twenty surgically resected sporadic MTCs, previously analyzed for RET mutations by Sanger sequencing using DNA from formalin-fixed paraffin-embedded samples, were investigated for intragenic mutations in 50 cancer-associated genes applying a multigene Ion AmpliSeq next-generation sequencing (NGS) technology. Thirteen (65 %) MTCs harbored a RET mutation; 10 were detected at both Sanger and NGS sequencing, while 3 undetected by Sanger were revealed by NGS. One of the 13 RET-mutated cases also showed an F354L germline mutation in STK11. Of the seven RET wild-type MTCs, four cases (57.1 %) harbored a RAS mutation: three in HRAS (all Q61R) and one in KRAS (G12R). The three remaining MTCs (15 %) resulted as wild-type for all the 50 cancer-related genes. Follow-up was available in all but one RET-mutated case. At the end of follow-up, 7 of 12 (58 %) RET-mutated patients had relapsed, while the 4 RAS-mutated MTC patients were disease-free. Two of the three patients with MTC wild-type for all 50 genes relapsed during the follow-up period. Detection of mutations by NGS has the potential to improve the diagnostic stratification of sporadic MTC.
Assuntos
Carcinoma Medular/genética , Neoplasias da Glândula Tireoide/genética , Quinases Proteína-Quinases Ativadas por AMP , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Neuroendócrino , Criança , Análise Mutacional de DNA/métodos , Feminino , Mutação em Linhagem Germinativa , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas c-ret/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Estudos RetrospectivosRESUMO
CONTEXT: Calcitonin (CT) measurement is crucial to the early diagnosis and the follow-up of medullary thyroid cancer (MTC). If the evaluation of stimulated CT levels is required, a provocative test can be performed, being the high-dose Ca test recently reintroduced in clinical practice. OBJECTIVE: Our objective was to identify gender-specific thresholds for MTC diagnosis in a large series of patients who underwent the Ca test. PATIENTS AND METHODS: A total of 91 patients (49 females and 42 males) underwent the Ca test (calcium gluconate, 25 mg/kg) before thyroidectomy and both basal CT (bCT) and stimulated CT (sCT) were compared with histological results by receiver operating characteristic plot analyses. To evaluate possible side effects of Ca administration, cardiac function has been extensively studied. RESULTS: bCT levels were found to harbor the same accuracy as sCT in the preoperative diagnosis of MTC. The best Ca thresholds for the identification of MTC were >26 and >68 for bCT and >79 and >544 pg/mL for sCT in females and males, respectively. The high tolerability and safety of the Ca test was demonstrated and advice offered to be followed before and during the test. CONCLUSIONS: Gender-specific bCT and sCT cutoffs for the identification of C-cell hyperplasia and/or MTC have been defined. The bCT and sCT were found to have a similar accuracy, indicating that serum CT assays with improved functional sensitivity may likely decrease the relevance of the stimulation test in several conditions. Finally, systematic cardiac monitoring confirms the safety of the Ca test.
Assuntos
Calcitonina/sangue , Gluconato de Cálcio , Carcinoma Medular/diagnóstico , Bócio Nodular/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Carcinoma Medular/sangue , Carcinoma Medular/cirurgia , Criança , Diagnóstico Diferencial , Feminino , Bócio Nodular/sangue , Bócio Nodular/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Glândula Tireoide/patologia , Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/cirurgia , TireoidectomiaRESUMO
To investigate whether further, diagnostic procedures should be recommended in patients with slight increase of preoperative serum basal calcitonin (bCT) levels in whom surgical treatment can be recommendable. Fourteen consecutive patients with nodular thyroid disease underwent thyroidectomy in our center for suspected medullary thyroid microcarcinoma (MTC) because their serum bCT levels were slightly higher than the upper limit of normal range. Serum bCT was measured by radioimmunoassay, normality range = 0-20 ng/L. Surgical specimens were examined by the same pathologist using histologic and immunohistochemistry techniques. An extensive search for parafollicular C-cell hyperplasia (CCH) and/or microscopic MTC foci was performed. At preoperative ultrasound, a single thyroid nodule was depicted in three patients while a multinodular goiter in 11. The bCT values ranged between 24.4 and 94.6 ng/L, median 42.2 ng/L while the pentagastrin-stimulated CT (sCT) values by pentagastrin test ranged between 61.5 and 1,262 ng/L, median 245.0 ng/L. Total thyroidectomy was performed in 13 patients, and lobectomy in the other one; central node dissection was also performed in eight cases. At histology, MTC was diagnosed in nine patients (64.3 %), showing a median maximum diameter of 6.1 mm (range, 1.5-17 mm); CCH was diagnosed in the other five patients (35.7 %). The pentagastrin stimulation test was obtained in all patients. It is worth noting that a very high increase of sCT >100 ng/mL was observed in 5/9 patients with MTC and in 2/4 patients with HCC, therefore suggesting the absence of a relationship between the entity of response to pentagastrin test with a specific pathology (MTC vs. HCC). In six patients, the MTC was the nodule on which preoperative FNAC had been performed, while in other three patients preoperative FNAC had been performed on a different nodule from the MTC. Based on our experience, in case of the pentagastrin stimulation test with sCT <100 ng/L and a single nodule, the CT assay on FNAC may be useful, subsequently lobectomy with definitive histological diagnosis is recommended. In case of the Pg test with sCT <100 ng/L and bilateral goiter, total thyroidectomy with histological diagnosis is recommended. In this way, as for the surgical procedure, total thyroidectomy is recommended in cases of bilateral goiter, while lobectomy can be offered for cases with single nodes with serum dosage of bCT in the strict follow up. In case of the pentagastrin stimulating test with sCT <100 ng/L and bilateral goiter, total thyroidectomy with histological diagnosis is recommended.
Assuntos
Adenocarcinoma Folicular/sangue , Biomarcadores Tumorais , Calcitonina/sangue , Carcinoma Medular/sangue , Nódulo da Glândula Tireoide/sangue , Tireoidectomia/métodos , Adenocarcinoma Folicular/diagnóstico por imagem , Adenocarcinoma Folicular/patologia , Adenocarcinoma Folicular/cirurgia , Adulto , Idoso , Biópsia por Agulha Fina/métodos , Carcinoma Medular/diagnóstico por imagem , Carcinoma Medular/patologia , Carcinoma Medular/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pentagastrina , Período Pré-Operatório , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/cirurgia , UltrassonografiaRESUMO
BACKGROUND: Anaplastic thyroid carcinoma (ATC) and primary thyroid lymphoma (PTL) are uncommon tumors of the thyroid gland with several overlapping clinical and pathologic features that may render their differentiation difficult in fine-needle aspiration (FNA) cytology. MicroRNA (miRNA) signatures have been recently reported as useful diagnostic tools applied to cytology specimens. METHODS: Smears of 23 ATCs, 14 PTLs, and 20 non-neoplastic materials with multinodular goiter (MNG) were retrieved and classified based on their cytologic features and flow cytometric profiles. The ATC-related expression of hsa-miR-26a, hsa-miR-146b, hsa-miR-221, and hsa-miR-222 was quantified using quantitative reverse transcriptase-polymerase chain reaction analysis. RESULTS: All miRNAs were remarkably up-regulated in ATC samples compared with PTL samples (P < .01). Moreover, expression levels of hsa-miR-146b, hsa-miR-221, and hsa-miR-222 were significantly higher in ATCs than in MNG samples (P < .01). Significant down-regulation of hsa-miR-26a was observed in PTLs compared with MNG samples, whereas hsa-miR-146b was overexpressed. Receiver operating characteristic analysis was used to determine the optimal cutoff for distinguishing ATC from PTL. The estimated receiver operating characteristic thresholds displayed a sensitivity level greater than 0.80 in achieving a diagnosis of PTL, allowing the correct identification of 13 of 14 PTL samples (93%). CONCLUSIONS: Histotype-specific miRNA signatures can provide new insight into the molecular mechanisms of thyroid carcinogenesis. The tested 4-miRNA signature is a promising diagnostic tool for differentiating ATC from PTL and non-neoplastic MNG, even in the presence of scant material obtained from minimally invasive procedures.