979 resultados para Lymph node metastasis
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The aim of this study was to investigate the frequency of axillary metastasis in women with tubular carcinoma (TC) of the breast. Women who underwent axillary dissection for TC in the Western Sydney area (1984-1995) were identified retrospectively through a search of computerized records. A centralized pathology review was performed and tumours were classified as pure tubular (22) or mixed tubular (nine), on the basis of the invasive component containing 90 per cent or more, or 75-90 per cent tubule formation respectively. A Medline search of the literature was undertaken to compile a collective series (20 studies with a total of 680 patients) to address the frequency of nodal involvement in TC. A quantitative meta-analysis was used to combine the results of these studies. The overall frequency of nodal metastasis was five of 31 (16 per cent); one of 22 pure tubular and four of nine mixed tumours (P = 0.019). None of the tumours with a diameter of 10 mm or less (n = 16) had nodal metastasis compared with five of 15 larger tumours (P = 0.018). The meta-analysis of 680 women showed an overall frequency of nodal metastasis in TC of 13.8 (95 per cent confidence interval 9.3-18.3) per cent. The frequency of nodal involvement was 6.6 (1.7-11.4) per cent in pure TC (n = 244) and 25.0 (12.5-37.6) per cent in mixed TC (n = 149). A case may be made for observing the clinically negative axilla in women with a small TC (10 mm or less in diameter).
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INTRODUÇÃO: O carcinoma oculto é uma entidade pouco frequente, que se define como a presença de metástases com tumor primário indetetável na altura da apresentação. O prognóstico da maioria dos casos de tumor oculto é reservado, no entanto, o desenvolvimento de técnicas imunohistoquímicas que permitem a caracterização do tumor, tornaram alguns subgrupos de tumor oculto potencialmente curáveis. A presença de adenopatias axilares é a forma de apresentação do cancro da mama em 0,3-1% das mulheres, sendo a origem mais provável a mama ipsilateral. CASO CLÍNICO: Os autores relatam dois casos clínicos de tumor oculto da mama: Caso 1: Doente de 57 anos, com antecedentes familiares de primeiro e segundo grau de cancro da mama, com estudo genético negativo. Recorreu à consulta por adenopatia axilar direita.Exame objetivo (EO), mamografia + ecografia mamária normais. Microbiópsia (MB) ganglionar:metástase de carcinoma compatível com origem na mama, recetores de estrogénios (RE) +, HER2 +, CK7 +, Ca125 +, CK20 (-). RMN mamária e PET não identificaram tumor primário. Procedeu-se a dissecção axilar: 10 gânglios sem metástases. Realizou terapêutica adjuvante com quimioterapia (QT) e imunoterapia (IT). Manteve follow-up regular com EO, RMN e mamografia alternadas até aos 4 anos sem alterações. Aos 4,5 anos detetou-se ao E.O. nódulo palpável na mama direita e nódulo axilar. Mamografia + ecografia: lesão sólida suspeita (R5) cuja caracterização histológicademonstrouCDIG3, recetores hormonais (-) (RH), HER2 3+, Ki67 >30%. A TC TAP e a cintigrafia óssea não revelaram alterações. Em reunião multidisciplinar de decisão terapêutica (RMDT) decidiu-serealizar mastectomia total direita + mastectomia profilática contralateral com reconstrução. Exame histológico:CDI G3 com 22mm,confirmando-se a caracterização imunohistoquímica, com invasão vascular e presença de 3 gânglios com metástase e extensão extracapsular (T2 N2). Realizou terapêutica adjuvante com QT + IT+ Radioterapia (RT) da parede torácica e ganglionar. Um ano após a mastectomia, a doente mantém-se em follow-up sem sinais de recidiva. Caso 2: Doente de 50 anos, com antecedentes familiares de primeiro grau de cancro da mama. Recorreu à consulta por nódulo da axila esquerda e nódulo da mama direita com 2 meses de evolução. EO: nódulo palpável da mama direita e duas adenopatias axilares à esquerda. Mamografia + eco: microcalcificações atípicas da mama esquerda (R5) ealterações benignas da mama direita (R2). Realizaram-se microbiópsia por estereotaxia e biópsia assistida por vácuo da mama esquerda e citologia aspirativa de agulha fina (CAAF) de nódulo da mama direita:sem alterações neoplásicas. A biópsia de adenopatia axilar revelou metástase ganglionar de carcinoma compatível com origem na mama, RH (-), GCDFP15 (-),HER2 3+ e CK7 +.A RM mamária revelou apenas lesões benignas. TC TAP, ecografia abdominal e cintigrafia óssea normais. PET: lesão localizada na axila esquerda, nos três níveis axilares. Por recusa da doente em realizar microbiópsias adicionais ou mastectomia radical modificada, optou-se por realizar dissecção axilar esquerda. Exame histológico: 7 em 14 gânglios com metástases, morfologia e estudo imunohistoquímico concordantes com o anterior. Em RMDT foi decidida terapêuticaadjuvante com RT, QT e IT que a doente se encontra no momento a realizar. DIAGNÓSTICOS DIFERENCIAIS/ DISCUSSÃO A presença de adenopatias axilares relaciona-se na maioria dos casos com processos benignos, mas naqueles em que se diagnostica uma neoplasia maligna, mais de 50% correspondem a carcinoma da mama. Outras neoplasias que se podem apresentar com metástases axilares são: linfoma, melanoma, sarcoma, tiróide, pulmão, estômago, ovário, útero. A avaliação diagnóstica deve incluir além do exame físico, a biópsia ganglionar (para exame histológico e caracterização imunohistoquímica), mamografia, ecografia mamária e ressonância magnética mamária, eventual TC toraco-abdominal, cintigrafia óssea nas mulheres sintomáticas, existindo controvérsia sobre autilidade da PET. CONCLUSÕES O tumor oculto representa um problema diagnóstico e um desafio terapêutico. O carcinoma da mama apresentando-se sob a forma de metástase axilar sem tumor primário identificável e sem doença à distância, considera-se um dos casos potencialmente curáveis, se for tratado de acordo com as guidelines para o estadio II do cancro da mama. A abordagem recomendada inclui dissecção axilar, de importância crucial pela informação prognóstica que guiará o restante tratamento e por ajudar no controlo local da doença. A terapêutica adequada da mama ipsilateral é controversa, e pode passar pela mastectomia radical modificada ou RT. Não existem até à data estudos randomizados comparando a mastectomia versus RT mamária e os estudos retrospetivos disponíveis não apresentam resultados consensuais. A decisão de RT da parede torácica pós-mastectomia e de terapêutica adjuvante deverá ser tomada tendo em conta as guidelines publicadas. BIBLIOGRAFIA 1- www.uptodate.com; Kaklamani, V., et al; “Axillary node metastases with occult primary breast cancer”; Mar 2012 2- Wang, J., et al; “Occult breast cancer presenting as metastatic adenocarcinoma of unknown primary: clinical presentation, immunohistochemistry, and molecular analysis”; Case Rep Oncol 2012;5:9-16 3- Takabatake, D.; “Two cases of occult breast cancer in which PET-CT was helpful in identifying primary tumors”; Breast Cancer (2008) 15:181-184 4- Kinoshita, S., et al.; “Metachronous secondary primary occult breast cancer initially presenting with metastases to the contralateral axillary lymph nodes: report of a case”; Breast Cancer (2010) 17:71-74 5- Bresser, J., et al; “Breast MRI in clinically and mammographically occult breast cancer presenting with an axillary metastasis: a systematic review”; EJSO 36 (2010) 114-119 6- Sharon, W., et al.; “Benefit of ultrasonography in the detection of clinically and mammographically occult breast cancer”; World J Surg (2008) 32:2593-2598 7- Masinghe, S.P., et al.; “Breast radiotherapy for occult breast cancer with axillary nodal metastases – does it reduce the local recurrence rate and increase overall survival?”; Clinical Oncology 23 (2011) 95-100 8- Altan, E., et al.; “Clinical and pathological characteristics of occult breast cancer and review of the literature”; J Buon 2011 Jul-Sep;16(3):434-6
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PURPOSE: Epithelial cell adhesion molecule (Ep-CAM) recently received increased attention not only as a prognostic factor in breast cancer but also as a potential target for immunotherapy. We examined Ep-CAM expression in 402 consecutive node-negative breast cancer patients with long-term follow-up not treated in the adjuvant setting. EXPERIMENTAL DESIGN: Ep-CAM expression was evaluated by immunostaining. Its prognostic effect was estimated relative to overexpression/amplification of HER-2, histologic grade, tumor size, age, and hormone receptor expression. RESULTS: Ep-CAM status was positive in 106 (26.4%) patients. In multivariate analysis, Ep-CAM status was associated with disease-free survival independent of age, pT stage, histologic grade, estrogen receptor (ER), progesterone receptor (PR), as well as HER2 status (P = 0.028; hazard ratio, 1.60; 95% confidence interval, 1.05-2.44). Recently, so-called triple-negative (HER-2, ER, and PR) breast cancer has received increased attention. We noticed a similar association of Ep-CAM with disease-free survival in the triple-negative group as for the entire cohort. CONCLUSION: In this study of untreated breast cancer patients, Ep-CAM overexpression was associated with poor survival in the entire cohort and in the subgroup of triple-negative breast cancer. This suggests that Ep-CAM may be a well-suited target for specific therapies particularly in HER-2-, ER-, and PR-negative tumors.
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BACKGROUND: The International Breast Cancer Study Group (IBCSG) conducted two complementary randomized trials to assess whether a treatment-free gap during adjuvant chemotherapy influenced outcome. PATIENTS AND METHODS: From 1993 to 1999, IBCSG Trials 13-93 and 14-93 enrolled 2215 premenopausal and postmenopausal women with axillary node-positive, operable breast cancer. All patients received cyclophosphamide (Cytoxan, C) plus either doxorubicin (Adriamycin, A) or epirubicin (E) for four courses followed immediately (No Gap) or after a 16-week delay (Gap) by classical cyclophosphamide, methotrexate, and fluorouracil (CMF) for three courses. The median follow-up was 7.7 years. RESULTS: The Gap and No-Gap groups had similar disease-free survival (DFS) and overall survival (OS). No identified subgroup showed a statistically significant difference, but exploratory subgroup analysis noted a trend towards decreased DFS for Gap compared with No Gap for women with estrogen receptor (ER)-negative tumors not receiving tamoxifen, especially evident during the first 2 years. CONCLUSIONS: A 16-week gap between adjuvant AC/EC and CMF provided no benefit and may have increased early recurrence rates in patients with ER-negative tumors.
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Apart from therapeutic advances related to new treatments, our practices in the management of early breast cancer have been modified by to key organizational settings (1) mass screening, substantially altering the presentation and epidemiology of breast cancer and (2) the development of guidelines to ensure that any patient management is in agreement with the demonstrated impact in the adjuvant treatment. In daily practice, the impact of screening and guidelines recommendations has put us now in a paradoxical situation: while the majority of non-metastatic breast cancers treated in the hexagon are node negative, most of the results of clinical studies on chemotherapy and targeted therapies today arise from populations predominantly node positive. Therefore, it seemed legitimate to convene a working group around a reflection on the directions of adjuvant chemotherapy in a growing node negative population in order to better respond to the questions of the field oncologists, trying to address the discrepancies between different existing guidelines.
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BACKGROUND: A 70-gene signature was previously shown to have prognostic value in patients with node-negative breast cancer. Our goal was to validate the signature in an independent group of patients. METHODS: Patients (n = 307, with 137 events after a median follow-up of 13.6 years) from five European centers were divided into high- and low-risk groups based on the gene signature classification and on clinical risk classifications. Patients were assigned to the gene signature low-risk group if their 5-year distant metastasis-free survival probability as estimated by the gene signature was greater than 90%. Patients were assigned to the clinicopathologic low-risk group if their 10-year survival probability, as estimated by Adjuvant! software, was greater than 88% (for estrogen receptor [ER]-positive patients) or 92% (for ER-negative patients). Hazard ratios (HRs) were estimated to compare time to distant metastases, disease-free survival, and overall survival in high- versus low-risk groups. RESULTS: The 70-gene signature outperformed the clinicopathologic risk assessment in predicting all endpoints. For time to distant metastases, the gene signature yielded HR = 2.32 (95% confidence interval [CI] = 1.35 to 4.00) without adjustment for clinical risk and hazard ratios ranging from 2.13 to 2.15 after adjustment for various estimates of clinical risk; clinicopathologic risk using Adjuvant! software yielded an unadjusted HR = 1.68 (95% CI = 0.92 to 3.07). For overall survival, the gene signature yielded an unadjusted HR = 2.79 (95% CI = 1.60 to 4.87) and adjusted hazard ratios ranging from 2.63 to 2.89; clinicopathologic risk yielded an unadjusted HR = 1.67 (95% CI = 0.93 to 2.98). For patients in the gene signature high-risk group, 10-year overall survival was 0.69 for patients in both the low- and high-clinical risk groups; for patients in the gene signature low-risk group, the 10-year survival rates were 0.88 and 0.89, respectively. CONCLUSIONS: The 70-gene signature adds independent prognostic information to clinicopathologic risk assessment for patients with early breast cancer.
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PURPOSE: Local breast cancer relapse after breast-saving surgery and radiotherapy is associated with increased risk of distant metastasis formation. The mechanisms involved remain largely elusive. We used the well-characterized 4T1 syngeneic, orthotopic breast cancer model to identify novel mechanisms of postradiation metastasis. EXPERIMENTAL DESIGN: 4T1 cells were injected in 20 Gy preirradiated mammary tissue to mimic postradiation relapses, or in nonirradiated mammary tissue, as control, of immunocompetent BALB/c mice. Molecular, biochemical, cellular, histologic analyses, adoptive cell transfer, genetic, and pharmacologic interventions were carried out. RESULTS: Tumors growing in preirradiated mammary tissue had reduced angiogenesis and were more hypoxic, invasive, and metastatic to lung and lymph nodes compared with control tumors. Increased metastasis involved the mobilization of CD11b(+)c-Kit(+)Ly6G(high)Ly6C(low)(Gr1(+)) myeloid cells through the HIF1-dependent expression of Kit ligand (KitL) by hypoxic tumor cells. KitL-mobilized myeloid cells homed to primary tumors and premetastatic lungs, to give rise to CD11b(+)c-Kit(-) cells. Pharmacologic inhibition of HIF1, silencing of KitL expression in tumor cells, and inhibition of c-Kit with an anti-c-Kit-blocking antibody or with a tyrosine kinase inhibitor prevented the mobilization of CD11b(+)c-Kit(+) cells and attenuated metastasis. C-Kit inhibition was also effective in reducing mobilization of CD11b(+)c-Kit(+) cells and inhibiting lung metastasis after irradiation of established tumors. CONCLUSIONS: Our work defines KitL/c-Kit as a previously unidentified axis critically involved in promoting metastasis of 4T1 tumors growing in preirradiated mammary tissue. Pharmacologic inhibition of this axis represents a potential therapeutic strategy to prevent metastasis in breast cancer patients with local relapses after radiotherapy. Clin Cancer Res; 18(16); 4365-74. ©2012 AACR.
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In breast cancer, brain metastases are often seen as late complications of recurrent disease and represent a particularly serious condition, since there are limited therapeutic options and patients have an unfavorable prognosis. The frequency of brain metastases in breast cancer is currently on the rise. This might be due to the fact that adjuvant chemotherapeutic and targeted anticancer drugs, while they effectively control disease progression in the periphery, they only poorly cross the blood-brain barrier and do not reach effectively cancer cells disseminated in the brain. It is therefore of fundamental clinical relevance to investigate mechanisms involved in breast cancer metastasis to the brain. To date experimental models of breast cancer metastasis to the brain described in literature are based on the direct intracarotid or intracardiac injection of breast cancer cells. We recently established a brain metastasis breast cancer model in immunocompetent mice based on the orthotopic injection of 4T1 murine breast carcinoma cells in the mammary gland of syngeneic BALB/c mice. 4T1-derived tumors recapitulate the main steps of human breast cancer progression, including epithelial-to-mesenchymal transition, local invasion and metastatic spreading to lung and lymph nodes. 4T1 cells were engineered to stably express firefly Luciferase allowing noninvasive in vivo and ex vivo monitoring of tumor progression and metastatic spreading to target organs. Bioluminescence imaging revealed the appearance of spontaneous lesions to the lung and lymph nodes and, at a much lower frequency, to the brain. Brain metastases were confirmed by macroscopic and microscopic evaluation of the brains at necropsy. We then isolated brain metastatic cells, re-injected them orthotopically in new mice and isolated again lines from brain metastases. After two rounds of selection we obtained lines metastasizing to the brain with 100% penetrance (named 4T1-BM2 for Brain Metastasis, 2nd generation) compared to lines derived after two rounds of in vivo growth from primary tumors (4T1-T2) or from lung metastases (4T1-LM2). We are currently performing experiments to unravel differences in cell proliferation, adhesion, migration, invasion and survival of the 4T1-BM2 line relative to the 4T1-T2 and 4T1-LM2 lines. Initial results indicate that 4T1-BM2 cells are not more invasive or more proliferative in vitro and do not show a more mesenchymal phenotype. Our syngeneic (BALB/c) model of spontaneous breast carcinoma metastasis to the brain is a unique and clinically relevant model to unravel the mechanisms of metastatic breast cancer colonization of the brain. Genes identified in this model represent potentially clinically relevant therapeutic targets for the prevention and the treatment of brain metastases in breast cancer patients.
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Sentinel node (SN) status is the most important prognostic factor for localized melanoma. Usually, patients with Breslow thickness of less than 1.0 mm are not included in SN protocols. However, the literature presents a rate ranging from 3 to 7% of nodal recurrence in thin melanoma. Ulceration, regression and high mitotic rate have been considered to be indications for an SN biopsy. The metastatic potential of the vertical growth phase is uncertain. To correlate pathological features in thin melanoma with SN metastasis, we reviewed 358 patients submitted to SN biopsy. Seventy-seven patients with lesions of 1 mm or smaller were included in the study group. Histological evaluation of the primary tumor included thickness, Clark level, mitotic rate, ulceration, regression, and growth phase. Lymphoscintigraphy was performed on all patients. Lymphatic mapping and gamma probe detection were both used for SN biopsy. Histological examination of SN consisted of hematoxylin-eosin and immunohistochemical staining. Median follow-up was 37 months. Six patients had micrometastases. Statistical analysis by the Fisher test showed that ulceration (P = 0.019), high mitotic rate (P = 0.008) and vertical growth phase (P = 0.002) were positively correlated with micrometastases. If other studies confirm these results, more melanoma patients must be submitted to SN biopsy.
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Linfoma multicêntrico foi diagnosticado em um cão com dois anos de idade que apresentava insuficiência respiratória, aumento de volume abdominal (ascite) e linfoadenopatia generalizada. O exame imunoistoquímico revelou origem de células T com expressão CD3+ e CD79-. Após cinco semanas, o cão apresentou déficits neurológicos progressivos, sendo identificada a presença de linfócitos neoplásicos no líquor. O exame histopatológico demonstrou invasão de células neoplásicas no baço, linfonodos, cérebro e cerebelo.
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A linfadenectomia laparoscópica é realizada de forma rotineira na medicina, contudo é pouco utilizada na veterinária. Neste relato, um canino fêmea apresentando tumores na cadeia mamária esquerda (M4 e M5), foi submetido à aplicação intradérmica do azul de metileno estéril, ao redor do maior tumor (M5), buscando-se demarcação dos vasos linfáticos e linfonodos regionais. Após 15 minutos, iniciou-se a linfadenectomia abdominal videolaparoscópica na região inguinal esquerda, seguida da ovário-histerectomia (OVH) lapararoscópica com três portais. Realizou-se ainda mastectomia total unilateral esquerda. Pela histologia, obtiveram-se dois linfonodos abdominais livres de células tumorais. A paciente não apresentou recidiva em 60 dias.
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Recent data suggest that the generation of new lymphatic vessels (i.e. lymphangiogenesis) may be a rate-limiting step in the dissemination of tumor cells to regional lymph nodes. However, efforts to study the cellular and molecular interactions that take place between tumor cells and lymphatic endothelial cells have been limited due to a lack of lymphatic endothelial cell lines available for study. ^ I have used a microsurgical approach to establish conditionally immortalized lymphatic endothelial cell lines from the afferent mesenteric lymphatic vessels of mice. Characterization of lymphatic endothelial cells, and tumor-associated lymphatic vessels revealed high expression levels of VCAM-1, which is known to facilitate adhesion of some tumor cells to vascular endothelial cells. Further investigation revealed that murine melanoma cells selected for high expression of α4, a counter-receptor for VCAM-1, demonstrated enhanced adhesion to lymphatic endothelial cells in vitro, and increased tumorigenicity and lymphatic metastasis in vivo, despite similar lymphatic vessel numbers. ^ Next, I examined the effects of growth factors that regulate lymphangiogenesis, and report that several growth factors are capable of activating survival and proliferation pathways of lymphatic endothelial cells. The dual protein tyrosine kinase inhibitor AEE788 (EGFR and VEGFR-2) inhibited the activation of Akt and MAPK in lymphatic endothelial cells responding to multiple growth factors. Moreover, oral treatment of mice with AEE788 decreased lymphatic vessel density and production of lymphatic metastasis by human colon cancer cells growing in the cecum of nude mice. ^ In the last set of experiments, I investigated the surgical management of lymphatic metastasis using a novel model of sentinel lymphadenectomy in live mice bearing subcutaneous B16-BL6 melanoma. The data demonstrate that this procedure when combined with wide excision of the primary melanoma, significantly enhanced survival of syngeneic C57BL/6 mice. ^ Collectively, these results indicate that the production of lymphatic metastasis depends on lymphangiogenesis, tumor cell adhesion to lymphatic endothelial cells, and proliferation of tumor cells in lymph nodes. Thus, lymphatic metastasis is a multi-step, complex, and active process that depends upon multiple interactions between tumor cells and tumor associated lymphatic endothelial cells. ^
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To analyze the role of alpha4-integrins in lymphoma metastasis, sublines of the T-cell lymphoma LB were generated by retrovirus-mediated gene transfer that differ exclusively in the expression of alpha4-integrins. Using LB-alpha4 and control LB-NTK cells, we demonstrate that expression of alpha4-integrins strongly suppresses metastasis formation of LB lymphoma cells in secondary lymphoid organs such as spleen, mesenteric and peripheral lymph nodes, or Peyer's patches after i.v. injection into syngeneic BALB/c mice. Moreover, alpha4-integrin expression inhibited development of metastatic tumors in liver, lung, and kidney. Expansion of LB lymphoma cells in bone marrow was not affected by alpha4-integrin expression. In vivo migration assays using 51Cr-labeled lymphoma cells demonstrated that low-metastatic LB-alpha4 cells accumulated with the same efficiency as high-metastatic LB-NTK cells in all target organs examined and were even enriched in mucosal lymphoid organs. Collectively, these results indicate that alpha4-integrins inhibit metastasis formation of lymphoma cells at a stage subsequent to the invasion of target organs.
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We present a case of a postmenopausal woman diagnosed with an ovarian mass containing thyroid follicles and foci of papillary thyroid carcinoma during pathological examination. This patient referred having had a metachronous thyroid malignancy 10 years before. The differential diagnosis between a thyroid malignancy arising from a struma ovarii and a metastatic ovarian tumor originating from thyroid-cancer is challenging. Struma ovarii should be considered when thyroid components are the predominant element or when thyroid malignant tissue is identified within an ovarian lesion. Thyroid carcinoma arising from a struma ovarii is reported to occur in a minority of cases. Of these, papillary carcinoma is the most frequent subtype encountered. Regarding primary thyroid carcinomas, papillary carcinomas have a lower metastatic potential when compared to follicular carcinomas, and most of the metastases occur in the cervical lymph nodes. Ovarian metastases are exceedingly rare and generally associated with widespread disease. However, they must be considered in the presence of previous history of malignant thyroid carcinoma. The authors review the main clinical, imaging and therapeutic aspects of both these entities and present the most likely diagnosis.
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Paracoccidioidomycosis is a mycotic disease caused by a dimorphic fungus, Paracoccidioides brasiliensis (Pb), that starts with inhalation of the fungus; thus, lung cells such as DC are part of the first line of defense against this microorganism. Migration of DC to the lymph nodes is the first step in initiating T cell responses. The mechanisms involved in resistance to Pb infection are poorly understood, but it is likely that DC play a pivotal role in the induction of effector T cells that control Pb infection. In this study, we showed that after Pb Infection, an important modification of lung DC receptor expression occurred. We observed an increased expression of CCR7 and CD103 on lung DC after infection, as well as MHC-II. After Pb infection, bone marrow-derived DC as well lung DC, migrate to lymph nodes. Migration of lung DC could represent an important mechanism of pathogenesis during PCM infection. In resume our data showed that Pb induced DC migration. Furthermore, we demonstrated that bone marrow-derived DC stimulated by Pb migrate to the lymph nodes and activate a T helper (Th) response. To the best of our knowledge, this is the first reported data showing that Pb induces migration of DC and activate a T helper (Th) response.