Dissertations / Theses on the topic 'Differentiated thyroid cancers'

Le traitement initial des cancers différenciés de la thyroïde (CTD) consiste en une thyroïdectomie totale suivie, dans de nombreux cas par l’administration d’iode 131. Après thyroïdectomie totale, un traitement par iode 131 est indiqué en fonction des caractéristiques tumorales initiales. Chez les patients à risque élevé de rechute il est recommandé d’administrer une forte activité d’iode 131. Chez les patients à très faible risque il est recommandé de ne pas administrer d’iode 131. Dans le groupe intermédiaire, il a été montré par deux études prospectives multicentriques randomisées (ESTIMABL et HILO) qu’une activité de 1,1 GBq (30 mCi) administrée après TSHrh (Thyroid Stimulating Hormon recombinante humaine) était adaptée. La désescalade thérapeutique se poursuit dans le cadre d’un autre essai prospectif randomisé (ESTIMABL 2) comparant une activité de 30 mCi après injection de TSHrh à une simple surveillance. Chez les patients avec maladie résiduelle la tomographie par émission de positon couplée à un scanner (TEP/TDM) au fluorodesoxyglucose (FDG) est un examen clé avec une valeur à la fois diagnostique et thérapeutique. Les fixations de FDG permettent de localiser la maladie résiduelle, surtout lorsqu’elle ne capte pas l’iode. Chez les patients dont le site de récidive n’est pas déterminé par l’échographie cervicale, la TEP/TDM au FDG est plus sensible que la scintigraphie post-thérapeutique réalisée après administration d’une forte activité d’iode 131 (dite activité empirique) et est considéré comme l’examen de première intention. La réalisation d’une stimulation par TSHrh avant la TEP au FDG augmente le nombre de lésions détectées et donc sa sensibilité sans que les modifications thérapeutiques qui en découlent soient néanmoins significatives. Le rôle de la TEP FDG dans la sélection des patients nécessitant un traitement par inhibiteur de tyrosine kinase et dans l’évaluation antitumorale des inhibiteurs de tyrosine kinase reste à démontrer. L’utilisation d’ITK pour ré-induire les fixations d’iode 131 sont une voie majeure de développement pour les patients ayant une maladie réfractaire à l’iode 131
Initial treatment of differentiated thyroid cancer is based on a total thyroidectomy and in many cases on the administration of radioactive iodine. Following total thyroidectomy, radioactive iodine is given, based on the primary tumor characteristics. In case of a very low risk of recurrence it is recommended not to give radioactive treatment. In case of high risk patients, a high activity of radioactive iodine is given after TSH stimulation. In case of intermediate risk patients, two randomized prospective studies (ESTIMABL and HILO) have shown that an activity of 1,1 GBq (30 mCi) given after rhTSH (recombinant human Thyroid Stimulating Hormon) was adequate. A further step is taken towards less treatment has now been undertaken with the ESTIMABL2 study, a prospective randomized study comparing a treatment with 1,1 GBq (30 mCi) of radioactive iodine treatment to follow-up without ablation. In patients with persistent disease, positron emission tomography with computed tomography (PET/CT) is a key examination used for its diagnostic and prognostic value. Foci of FDG uptake can localize residual disease, especially when it does not take up radioactive iodine. In patients in whom the site of recurrence remains unknown after a neck ultrasonography PET/CT with FDG is more sensitive than a post-therapeutic whole body scan performed after the administration of a high activity of radioactive iodine (empiric iodine) and should be considered as the first examination to perform. Injections of rhTSH before doing FDG PET/CT allow to increase the number of lesions detected, however the treatment changes linked to this preparation remains minor. The role of FDG PET/CT in the selection of patients to tyrosine kinase inhibitors (TKI) and to assess metabolic tumor response remains to be explored. The use of TKI to reinduce radioactive iodine uptake is a major research subject for patients with radioactive iodine refractory disease

Les nodules thyroïdiens (NT) sont fréquents, et seuls 5-10% s'avèrent être cancéreux. La stratégie diagnostique qu'ils imposent est bien codifiée et permet de stratifier leur risque de malignité, mais ne permet toutefois pas de conclure sur la nature des NT dans 20-25% des cas, on parle alors de NT indéterminés (NTI). Cette situation conduit souvent à la réalisation d'une chirurgie diagnostique, retrouvant 66% de NT bénins. L'amélioration du diagnostic de ces NTI reste donc cruciale. Les cancers thyroïdiens différenciés (CDT) sont de très bon pronostic, grâce à des traitements reposant sur la chirurgie et la radiothérapie métabolique à l'iode 131, permettant de guérir la majorité des patients. Le suivi des CDT repose sur le dosage de la thyroglobuline (Tg) sérique, une molécule complexe. Toutefois, la Tg n'est pas spécifique des cellules cancéreuses thyroïdiennes, posant des défis d'interprétation. La découverte d'une forme de Tg plus spécifique aux cellules cancéreuses pourrait améliorer le suivi des CDT et servir d'outil diagnostic.Dans ce contexte, les objectifs de ma thèse ont été i) d'améliorer la prédiction du risque de malignité des NTI par l'utilisation d'algorithmes d'intelligence artificielle (IA) et d'une approche métabolomique, et ii) de mieux caractériser les modifications post-traductionnelles (MPT) de la Tg humaine afin de servir de base à l'identification d'une Tg spécifique des cellules cancéreuses thyroïdiennes, facilitant l'identification des récidives chez les patients traités pour un CDT. Pour ce faire, nous avons dans un premier temps comparé l'efficacité d'algorithmes d'IA pour prédire le risque de malignité des NTI à partir de données cliniques récoltées sur une cohorte rétrospective multicentrique de 1290 patients (1337 NT). L'utilisation d'un autoencodeur supervisé a obtenu les meilleurs scores de performance avec une accuracy de 85,19% (±1,5), une AUC de 82,99% (±1,73), et un F1 score de 84,02% (±1,66). Dans un deuxième travail, nous avons pu identifier une signature métabolomique sur des échantillons de cytoponction thyroïdienne par spectrométrie de masse en tandem couplée à la chromatographie liquide (LC-MS/MS), permettant de différencier les nodules bénins des nodules malins parmi les NTI. L'utilisation de l'autoencodeur supervisé sur cette signature métabolomique a permis d'atteindre des performances diagnostiques remarquables, avec une accuracy de 95,7% (0,842-1), une AUC de 94,5% (0,833-1) et un F1 score de 94,7% (0,842-1). En perspective, la validation prospective à grande échelle des résultats obtenus et l'adoption d'une approche hybride combinant données cliniques et métabolomiques (notamment sur des prélèvements moins invasifs qu'une cytoponction thyroïdienne) vont être débutés. Enfin, nous avons réalisé une cartographie exhaustive des MPT de la Tg humaine via une approche protéomique par nano LC-MS/MS pour mieux comprendre sa complexité. Cette étude a révélé un spectre plus large de sites de N-glycosylation, d'oxydation, et d'iodation que précédemment rapporté, fournissant une ressource précieuse pour les futures recherches visant à comprendre la modulation des MPT de la Tg et leur rôle. En perspective, l'identification des différences observables des MPT de la Tg entre cellules thyroïdiennes saines et cancéreuses pourrait permettre l'identification d'une Tg plus spécifique de ces dernières, facilitant l'identification des récidives chez les patients traités pour un CDT et offrant des innovations diagnostiques et thérapeutiques en oncologie thyroïdienne. Cette thèse ouvre ainsi la voie à de nouvelles stratégies diagnostiques et de suivi basées sur la métabolomique, la protéomique et l'intelligence artificielle dans le contexte des NT et CDT
Thyroid nodules (TN) are common, with only 5-10% being cancerous. The diagnostic strategy for TN is well-established, allowing stratification of their malignancy risk; however, it fails to determine the nature of TN in 20-25% of cases, known as indeterminate thyroid nodules (ITN). This often leads to diagnostic surgery, revealing benign nodules in 66% of cases. Improving the diagnosis of these ITN is therefore crucial. Differentiated thyroid cancers (DTC) have a very good prognosis, thanks to treatments involving surgery and radioactive iodine therapy, which cure the majority of patients. Follow-up of DTC relies on the measurement of serum thyroglobulin (Tg), a complex molecule. However, Tg is not specific to thyroid cancer cells, posing interpretation challenges. Discovering a form of Tg more specific to cancer cells could enhance DTC follow-up and serve as a diagnostic tool.In this context, the objectives of my thesis were: i) to improve the prediction of malignancy risk in NTI using artificial intelligence (AI) algorithms and a metabolomic approach, and ii) to better characterize the post-translational modifications (PTMs) of human Tg to serve as a basis for identifying a Tg specific to thyroid cancer cells, facilitating the identification of recurrences in patients treated for DTC. To achieve this, we first compared the efficacy of AI algorithms to predict the malignancy risk of NTI using clinical data collected from a retrospective multicentric cohort of 1290 patients (1337 TN). The use of a supervised autoencoder achieved the best performance scores with an accuracy of 85.19% (±1.5), an AUC of 82.99% (±1.73), and an F1 score of 84.02% (±1.66). In a second study, we identified a metabolomic signature from thyroid fine-needle aspiration (FNA) samples using tandem mass spectrometry coupled with liquid chromatography (LC-MS/MS), enabling the differentiation between benign and malignant nodules among ITN. The use of the supervised autoencoder on this metabolomic signature achieved remarkable diagnostic performance, with an accuracy of 95.7% (0.842-1), an AUC of 94.5% (0.833-1), and an F1 score of 94.7% (0.842-1). Prospectively, the large-scale validation of the obtained results and the adoption of a hybrid approach combining clinical and metabolomic data (especially from less invasive samples than thyroid FNA) are planned. Finally, we conducted an exhaustive mapping of the PTMs of human Tg using a proteomic approach by nano LC-MS/MS to better understand its complexity. This study revealed a broader spectrum of N-glycosylation, oxidation, and iodination sites than previously reported, providing a valuable resource for future research aimed at understanding the modulation and roles of Tg PTMs. Looking ahead, identifying observable differences in Tg PTMs between healthy and cancerous thyroid cells could lead to the identification of a Tg specific to the latter, facilitating the identification of recurrences in patients treated for DTC and offering diagnostic and therapeutic innovations in thyroid oncology. This thesis thus paves the way for new diagnostic and follow-up strategies based on metabolomics, proteomics, and artificial intelligence in the context of NT and DTC

L’imagerie scintigraphique des cancers thyroïdiens différenciés (CTD) présente la particularité d’utiliser deux radiopharmaceutiques, l’iode 131 (131I) et le 18-Fluorodésoxyglucose (18FDG). La fixation de ces traceurs dépend habituellement du degré de différenciation et de l’agressivité de la tumeur. L’objectif de ce travail était d’étudier l’apport de différents aspects techniques et d’instrumentation, à savoir l’imagerie hybride par TEMP/TDM et TEP/TDM, la point-spread function (PSF), la taille des voxels et la technologie TEP digitale, et d’explorer si d’autres traceurs TEP pouvaient présenter un intérêt. Le but de la première partie était d’étudier les performances de la TEP/TDM au 18FDG à l’étage cervical pour la détection de la maladie ganglionnaire. Une acquisition TEP/TDM dédiée a amélioré la détection de la maladie tumorale par rapport à l’acquisition classique. L’utilisation de la PSF a permis de détecter des tailles de lésions plus petites et la durée optimale de cette acquisition a été évaluée. Des reconstructions avec des tailles de voxels ultra-fines ont été réalisées sur TEP digitale pour étudier l’impact de la PSF et des voxels ultra-fins sur les données quantitatives. La seconde partie a porté sur l’imagerie 131I-TEMP/TDM et 18FDG-TEP/TDM, afin de quantifier le volume de la maladie persistante. Il a ainsi été montré que la masse tumorale était corrélée au risque post-opératoire et avait un impact sur la réponse au traitement. L’objectif de la troisième partie était d’étudier un autre traceur TEP, la 18-Fluorocholine (FCH), ainsi qu’un marqueur de la néovascularisation, l’antigène membranaire spécifique de la prostate (PSMA). Nos données suggèrent qu’un examen TEP à la FCH négatif au sein d’un nodule thyroïdien à cytologie indéterminée permettrait d’éliminer la malignité, et pourrait éviter des chirurgies inutiles. Par ailleurs, le marquage au PSMA évalué par immunohistochimie dans les néo-vaisseaux est associé à des facteurs de mauvais pronostic. D’autres études sont nécessaires pour confirmer l’intérêt éventuel des examens TEP à la FCH et au 68Ga-PSMA en oncologie thyroïdienne
Radioiodine (131I) and 18-Fluorodeoxyglucose (18FDG) are two radiopharmaceuticals used for scintigraphic imaging in differentiated thyroid cancers (DTC). Tumour uptake of each tracer depends on tumour differentiation and aggressiveness. Our goal was to further assess various technical aspects in DTC imaging workup, such as SPECT/CT and PET/CT, point-spread function (PSF), voxel size, digital PET, and to explore further other PET tracers. The aim of the first part was to assess the performance of 18FDG PET/CT for the detection of neck lymph node involvement. A dedicated PET/CT acquisition improved tumour detection compared to the whole-body acquisition. PSF reconstruction allowed detection of smaller cancer deposits and the optimal acquisition duration time was assessed. Using digital PET acquisitions, ultra-thin voxels reconstructions were performed. The impact of ultra-thin voxels and PSF on quantitative values was evaluated. The second part focused on 131I-SPECT/CT and 18FDG-PET/CT imaging, in an attempt to assess tumour burden of persistent disease. Tumor burden was correlated with the postoperative risk and affected the response to therapy. In the third part, another PET tracer, i.e. 18-Fluorocholine (FCH), and a marker of neovasculature, i.e. prostate-specific membrane antigen (PSMA), were studied. FCH PET/CT offered high negative predictive value to reliably exclude cancer in PET-negative nodules with indeterminate cytology and might prevent unnecessary surgeries. Also, PSMA expression assessed with immunohistochemistry was associated with poor prognosis factors. Further studies are needed to confirm new insights of FCH PET and 68Ga-PSMA PET in DTC

The most common type of thyroid cancer, differentiated thyroid cancer (DTC), is diagnosed by radioactive iodine whole body scanning (WBS) and treated with radiotherapy using iodine-13I C31 I). The success of this diagnosis/treatment approach relies on the relatively selective localisation of the sodium/iodide symporter (NIS) in cells of the thyroid gland. However, in some de-differentiated thyroid cancers, NIS expression is lost. This results in the inability of WBS to stage the disease and it also decreases the effectiveness of treatment with 131 I. A number of reports have shown that de-differentiated thyroid carcinomas, however, continue to express thyroid stimulating hormone receptor (TSHR). TSHR is, therefore, a potential target for the diagnosis and treatment of radioiodine resistant de-differentiated thyroid carcinoma. In this study an anti- TSHR mono clonal antibody (mAb9) and human recombinant TSH (rhTSH) were radio labelled and evaluated for their potential use in the diagnosis and treatment of radioiodine resistant thyroid cancer. A number of radiolabelling methods and quality control experiments were initially carried out to ensure high purity radiolabelled mAb9 and rhTSH were produced. In vitro studies were conducted to assess the binding affinity of 125I_mAb9, lllIn-mAb9 and 125I_rhTSH to the TSHR in thyroid cancer cell lines, TPC-I,FTC-133, and FRTL5, and in a TSHR transfected cell line, GPI. SPECT/CT aJimal studies were performed in mice to investigate whether 125I_mAb9, 111In-mAb9 and 125I_rhTSH bound to TSHR in the thyroid of mice in vivo. 125I_mAb9, 11lIn_mAb9 and 125I_rhTSH bound to GPI cells but did not bind specifically to the TSHR in FTC-133, TPC-I and FRTL5 cells as well as to the thyroid of normal mice in vivo. Radiolabelled mAb9 and radiolabelled rhTSH are therefore unlikely to be of use in the diagnosis and treatment of radioiodine resistant de-differentiated thyroid cancer.

Background: Differentiated thyroid cancer (DTC), although rare, is the commonest endocrine malignancy, with a significant recent increase in incidence. Natural history is well understood: the majority of patients have an extremely good prognosis, but with a tendency for late recurrences, up to twenty years post diagnosis. These features have combined to effect a lack of evidence underlying current practice, the majority of guidelines based around retrospective series and opinion. A number of validated risk stratification systems exist, unique to DTC, some applicable at the point of intervention. Although these systems reliably predict outcome, they are inconsistently used to guide the extent of intervention. As such, the three main facets of treatment, surgery to the thyroid, surgery to the lymph nodes, and radioiodine (RAI), are variably applied to the same extent of disease. This may depend at least partly upon the clinician‟s preference towards use of risk stratification systems. Consequently, low risk patients may be at risk of morbidities, both short and long term from unnecessarily aggressive interventions, despite consistently good prognosis. Rationalisation of the approach is attractive from a patient, provider, and health service perspectives; without controlled or long term data, such change in practice requires justification. Aim The overall aim of this thesis is to describe and compare the clinical effectiveness of risk stratified (RS) management of DTC, compared to non risk stratified (NRS) management, in an adult population. UK context is provided by description of current practice and long term disease specific outcomes. Three strands of work are combined to address this aim. Part One: Systematic Review A comparison of RS/NRS approaches necessitated objective and reproducible definition of practice overall, encompassing the three facets of intervention. Thereafter, rigorous methodology was applied to examine the clinical effectiveness of the two approaches, based on review of 76 datasets identified from the literature, with RS/NRS approach assigned; there were no relevant randomised trials nor prospective comparative series. Patients, disease and practice were described and compared, with outcome data grouped by safety, disease control, and survival. Sensitivity analysis was planned around population and practice items. Study quality vi was objectively assessed. Weighted mean effect sizes were calculated for RS/NRS cohorts and compared across the two intervention groups for each outcome, with findings further tested on sensitivity analysis. Broadly, equivalence was shown across the two treatment groups by outcome, with small differences consistent with disease biology/magnitude of intervention. Risk stratification appeared to be applicable not only to primary intervention, but also follow-up strategies. Variations in outcome definitions were highlighted, and a pragmatic, patient-centred definition favoured as an approach for future work. Lack of time-specific data was a significant limiting factor. Part Two: Description and Analysis of UK Practice With no UK dataset within the systematic review, validity for the findings was required, as well as the need to describe and compare practice and outcomes in a contemporary local context. The ideal dataset was defined and participants for a UK collaborative sought. Five centres contributed datasets of adequate quality, at least in part prospective, with time-specific outcome measures. Overall, UK practice was by definition risk stratified – and appeared increasingly so over time. There was considerable variation in practice across the five centres (2 NRS, 3RS), but all with consistent, equivalent outcomes compared with the review, despite patients of somewhat higher risk. Utilising methodologies from the systematic review, the analysis was repeated and augmented, confirming consistency in effect directions. Time-specific, adjusted outcome measures demonstrated a possible lack of effectiveness of RAI in high risk disease – a new finding worthy of further exploration. The comprehensive datasets further reinforced the need to work towards prospective, long term, time specific data with common agreed definitions, and suggestions are made how this can be achieved. Part Three: National Survey of Practice Preference The current UK preference for RS management, notwithstanding current service provision around thyroid cancer, is little known. Through cross-specialty survey, utilising a number of case scenarios validated by external experts, and gathering data on clinician demographics, this information was sought, in order to give further context to the above findings. A high degree of variation was identified within, and across scenarios; the least RS preference for intervention applied to the lowest risk scenarios, implying risk of over-treatment. RS preference was associated independently with fewer years in practice and high volume practice. Conclusion Based on the best available data, and supplemented by congruent, contemporary UK data and perspectives, this thesis confirms safety and equivalence of effectiveness of a risk stratified approach to the management of differentiated thyroid cancer, demonstrates considerable variations in practice and suggests possible tools towards building a better evidence base for the future.

INTRODUCTION: Thyroid cancer is the most common endocrine malignancy and its incidence is increasing, of which the most common subtype is papillary thyroid cancer. Risk factors for papillary thyroid cancer have been investigated extensively. Given the good prognosis of papillary thyroid cancer there is growing concern regarding the development of second primary malignancies following thyroid cancer. This study specifically considered breast cancer is the most common cancer in women and has been theorized to be associated with thyroid cancer under certain conditions. Multifocality is a risk factor for thyroid cancer that has not been extensively studied. Age is seen as a significant prognostic feature for all cancers. There has been few studies considering the effect of thyroidectomy for thyroid cancer in the elderly. This thesis aimed to add to the body of literature on risk factors for thyroid cancer to provide some insight and suggestions into the investigation, management and screening of the disease. METHOD: A series of three meta-analyses were performed to investigate risk factors of thyroid cancer and to determine its prognostic significance. We followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. A systematic search of the databases MEDLINE (from 1950), PubMed (from 1946), to identify relevant articles. Relevant data was tabulated then analyzed using Comprehensive Meta-Analysis software to determine summary effect. RESULTS: This study identified an association between breast cancer and thyroid cancer. It found that there is a greater risk of thyroid cancer following breast cancer than breast cancer following thyroid cancer. Additionally, multifocality was confirmed as a significant risk factor for disease progression, showing increased risks of lymph node metastases, extrathyroidal extension and recurrence. Finally, this thesis emphasized the increased risk of thyroidectomy for thyroid cancer in the elderly, demonstrating that risk of mortality, recurrence and post-operative complications is increased in patients above the age of 60. CONCLUSIONS: Finding as association between breast cancer and thyroid cancer opens up new opportunities for research into the association between the two cancers. Increased risk can direct clinicians to guide investigations and screening. Multifocality as a risk factor for thyroid cancer can guide clinical decision making regarding operative and post-operative management. The increased risk of mortality, recurrence and complication rates in elderly patients suggest that patients should undergo aggressive surgical management as early as possible to reduce risk of mortality and morbidity for the patient. The current thesis provided evidence that the above mentioned risk factors should influence investigation, management and screening for patients diagnosed with thyroid cancer.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
With the use of sensitive imaging methods, there is an increase in thyroid nodules diagnosed. Even the CDT (differentiated thyroid cancer) being proportionately rare, its incidence is increasing, especially small tumors whose clinical outcome is uncertain. It is observed that in clinical practice most patients with CDT develops well when properly treated, mortality rates similar to the general population. On the other hand, a non-negligible percentage has relapses and some eventually not respond to conventional therapies, and died. It can be seen that with the need to identify markers that can predict the behavior of tumors, mainly due to the variable clinical disease progression. With these data, some researchers in search of these markers, are studying a possible relationship of hormonal and reproductive factors in the evolution of CDT. This study analyzes the immunoreactivity of α estrogen receptor (ERα) and progesterone receptor (PR), correlating it with clinical features in 80 female and male patients with papillary thyroid cancer (PDT) and follicular thyroid cancer (FDT ) with materials related to thyroidectomy pieces performed at the University Hospital Walter CantÃdio (HUWC) in the period from 2010 to 2014. There was a predominance of female patients (87.5%), older than or equal to 40 years (68.57%), average age 49.12, tumor size> 1 cm (69.04%), papillary histological type (95.24%), with location in one wolf, not multicenter, (61.90 %), lack of angiolymphatic invasion (67.85%), absence of invasion of the capsule (75%) without Hashimoto\'s thyroiditis (73.80%). In adjacent normal tissues it was observed that ER expression (77.77%) is greater than the PR expression (47.05%). In tumors observed the opposite, ERα (43.75%) and PR (47.5%) with a higher PR expression, these data were correlated with the clinical characteristics of tumors, such as gender, tumor size, age the diagnosis, capsular invasion, lymphatic invasion, Hashimoto\'s thyroiditis, tumor location, histological type and variants.
Com o uso de mÃtodos sensÃveis de imagem, observa-se um aumento nos nÃdulos tireoidianos diagnosticados. Mesmo o CDT (cÃncer diferenciado de tireÃide) sendo proporcionalmente raro, sua incidÃncia vem aumentando, especialmente de tumores pequenos, cuja evoluÃÃo clÃnica à incerta. Observa-se na prÃtica clÃnica que a maioria dos pacientes com CDT evolui bem quando adequadamente tratada, com Ãndices de mortalidade similares à populaÃÃo geral. Por outro lado, um percentual nÃo desprezÃvel apresenta recidivas e alguns eventualmente nÃo respondem Ãs terapias convencionais, evoluindo para Ãbito. Percebe-se com isso a necessidade de identificaÃÃo de marcadores que possam predizer o comportamento dos tumores devido, sobretudo, à variabilidade na progressÃo clÃnica da doenÃa. Com esses dados, alguns pesquisadores, em busca desses marcadores, estÃo estudando uma possÃvel relaÃÃo de fatores hormonais e reprodutivos na evoluÃÃo do CDT. No presente estudo analisamos a imunoexpressÃo do receptor de estrogÃnio α (ERα) e receptor de progesterona (PR), correlacionando-a com caracterÃsticas clÃnicas, em 80 pacientes femininos e masculinos com cÃncer papilÃfero de tireÃide (PDT) e cÃncer folicular de tireÃide (FDT), utilizando material referente a peÃas de tireoidectomia realizadas no Hospital UniversitÃrio Walter CantÃdio (HUWC), no perÃodo de 2010 a 2014. Observou-se o predomÃnio de pacientes do sexo feminino (87,5%), com idade superior ou igual a 40 anos (68,57%), mÃdia de idade 49,12, tumor com dimensÃo >1cm (69,04%), tipo histolÃgico papilÃfero (95,24%), com localizaÃÃo em Ãnico lobo, nÃo multicÃntrico, (61,90%), ausÃncia de invasÃo angiolinfÃtica (67,85%), ausÃncia de invasÃo da cÃpsula (75%), sem Tireoidite de Hashimoto (73,80%). Em tecidos normais adjacentes observou-se que a expressÃo de RE (77,77%) à maior que a expressÃo de RP (47,05%). Em tumores observou-se o contrÃrio, ERα (43,75%) e PR (47,5%) sendo maior a expressÃo de RP, esses dados foram correlacionados com as caracterÃsticas clÃnicas dos tumores, como: sexo, tamanho do tumor, idade ao diagnÃstico, invasÃo capsular, invasÃo linfÃtica, tireoidite de Hashimoto, localizaÃÃo do tumor, tipo histolÃgico e variantes.

Patients with differentiated thyroid cancer (DTC) are usually managed with total thyroidectomy and subsequent radioiodine ablation of the remnant thyroid tissue. Since these patients become athyrotic, L-throxine (L-T4) therapy is required for life, in order to replace the thyroid hormones and also to suppress the endogenous thyroid stimulating hormone (TSH) which may have a growth-promoting effect on any residual thyroid cancer cells. The approximate dose required to achieve this suppression is about 2 g/kg. However, there is wide variation between patients in their L-T4 requirement. Although factors such as the timing of the dose, compliance, weight and age play important roles, genetic factors are also thought to be important in this dose variability. Therefore, the aims of this study are to identify and evaluate the association of polymorphisms in six genes [(iodothyronine deiodinases (DIO) 1, 2 and 3, paired box gene 8 (PAX8), thyroid stimulating hormone subunit β (TSHβ), and sodium iodide symporter (NIS)], involved in thyroid hormone metabolic and functional pathways with DTC risk and L-T4 dose requirement.

Inflammation is an essential component of malignancies, including differentiated thyroid cancer (DTC). Thyroid cancer microenvironment is composed of a mixture of immune cells and soluble mediators. Among them, the chemokine CXCL8 exerts multiple pro-tumorigenic activities, including a chemotactic action on circulating neutrophils, induction of tumor cells growth, increase in angiogenesis and induction of the epithelial to mesenchymal transition, which promotes cell migration. Clinical studies in patients affected by several types of cancer evidenced that CXCL8 serum levels reflect the tumor burden and are related with the tumor aggressiveness. Solid evidence indicates that CXCL8 targeting can reduce tumor progression. The controversial relationship between inflammation and thyroid cancer tumorigenesis involves also the debated topic of the association between chronic-autoimmune-thyroiditis (CAT) and (DTC). DTCs are often diagnosed in the context of CAT and display an inflammatory-immune cells infiltration at histology, but whether the malignant transformation is promoted by the inflammatory response, or the peri-tumoral inflammation is induced by cancer-specific inflammatory molecules is still a matter of debate. This thesis project had two principal aims, i) to investigate the role of a pro-tumorigenic chemokine (CXCL8) in thyroid cancer microenvironment and to test in vitro the modulating properties of two different pharmacologic agents (PLX4720 and phenformin) and ii) to evaluate if CAT is a risk factor for the de novo development of DTC through a longitudinal population study. For Aim 1, thyroid cancer cell lines both BRAFV600E mutated (BCPAP, 8305C, 8505C) and RET/PTC rearranged (TPC-1), and normal human thyrocytes (NHT) were cultured alone or after treatment with two PLX4720 ore phenformin at increasing concentrations. CXCL8 concentrations were measured in the cell supernatants. Cell viability was evaluated through WST-1 and Annexin/propidium assay. Metastatic potential was assessed with migration assay and colony formation assay. For Aim 2, a retrospective longitudinal cohort study was designed including 510 CAT patients with a 10-years follow-up. The results of the first part of the thesis demonstrate that thyroid cancer cells secrete high amounts of CXCL8 and that both PLX4720 and phenformin are able to exert several anti-cancer activities within cancer microenvironment that are in part due to the inhibition of CXCL8 secretion. The results of the second part of the study indicate that the presence of CAT is not a risk factor for the new onset of DTC during long-term follow-up. The results of this thesis project suggest that two different kinds of inflammation (cancer-related and autoimmunity-related) exert different effects on DTC microenvironment and could have opposite effects on DTC development and prognosis.

Thyroid cancer is the most common endocrine malignancy and his global incidence has rapidly increased in last decades. Despite the major part of thyroid cancer is represented by well differentiated hystotypes, the acquisition of additional mutations, such as p53 and β-catenin ones, causes loss of differentiation and confer high malignancy. Current treatment for undifferentiated thyroid cancers is regarded as almost ineffective, with a median survival of 3- 4 months, somewhat better in localized and worse in metastatic disease. SP600125 is a multi-kinase inhibitor that has recently been shown to be a promising anticancer drug. In the last five years it has been proved able to induce endoreduplication and subsequent polyploidization, but there are contrasting results about its intracellular actions and there is no evidence on the specific mechanism of action. Moreover, in 2012, SP600125 has been found to be the most effective against p53 deficient cells among more than 300 screened compounds. However, opposite results have also been obtained depending on cell type, concentration and time of incubation. In the current study the effects of micromolar doses of SP600125 have been characterized in six thyroid cancer cell lines with different p53 status. The results show that at low concentrations SP600125 dramatically reduces the proliferation of p53 mutated cells, with lesser effects on p53 null and no effects on the wild-type ones. In p53 mutated cells it has been proved able to induce p53 nuclear translocation and phosphorylation at serine 15; this modification resulted to be responsible of increased levels of p21. Importantly other considerable novel effects have been revealed. Firstly, SP600125 caused alterations of microtubule dynamics in p53 mutated cells, with increase of acetylation levels and loss of Microtubule Organizing Center (MTOC)-periphery organization. These effects were accompanied by alterations in cellular morphology and in late endosome/lysosome trafficking. Endoreduplication and alteration of microtubule dynamics finally resulted in aberrant mitosis and cell death. The second mechanism involves alteration of cellular motility: different kinases involved in this process are affected by SP600125 treatment and β-catenin remains at the intercellular junctions in affected cells,consistent with a failure of cell detachment (a figure consistent with inhibition of cell migration/motility). Microtubule alterations concomitantly also account for motility alterations. Both tubulin and β-catenin variations are due to HDAC6 activity alterations. This enzyme regulates the levels of acetylation of these proteins and is profoundly inhibited following SP600125 in p53 deficient cells. Alteration of HDAC6 activity is hypothesized to be the result of SP600125 direct inhibition of ROCK2, an upstream kinase regulator of HDAC6 activity. In conclusion SP600125 is a promising drug particularly active on p53-mutated cancers at concentrations unable to affect normal cell viability. The effects of SP600125 action include arrest of tumor growth, and importantly induction of tumor cell death and metastatic diffusion inhibition.

要旨pdfファイル:タイトル「Diagnostic Value of Technetium-99m Isonitrile (^[99m]Tc-MIBI) Scintigraphy in Detecting Thyroid Cancer Metastases : A Critical Evaluation」
Kyoto University (京都大学)
0048
新制・課程博士
博士(医学)
甲第7742号
医博第2095号
新制||医||710(附属図書館)
UT51-99-G336
京都大学大学院医学研究科内科系専攻
(主査)教授 山邊 博彦, 教授 高橋 隆, 教授 小西 淳二
学位規則第4条第1項該当

Contexte: L’iode est un micronutriment provenant des aliments. Il est établi que, dans les régions d'endémie goitreuse caractérisées par un apport d'iode insuffisant, l’incidence des goitres et des cancers différenciés de la thyroïde (CDT) de type folliculaire est plus élevée qu'ailleurs. En revanche, l’influence de l’apport alimentaire en iode sur le risque de CDT de type papillaire, forme représentant actuellement plus de 80% des CDTs dans la plupart des pays, ne fait pas l’objet d’un consensus. Il semble cependant que cette incidence soit plus élevée dans les îles du pacifique qu’ailleurs. Par ailleurs, les propriétés de protection redox du sélénium pourraient protéger la glande thyroïdienne et aider à maintenir la production d'hormones thyroïdiennes, mais la relation entre l’apport en sélénium et le CDT n’avait été que très peu étudiée.Objectifs: L’objectif général de ce travail de thèse était d'explorer la relation entre l'apport alimentaire en iode et le risque de CDT. Plus spécifiquement, il s’agissait 1) d’étudier la relation entre l’apport alimentaire en iode et le risque de CDT dans les cinq études cas-témoins du consortium Epi-Thyr, conduites en Nouvelle Calédonie, en Polynésie Française, en France métropolitaine (deux études) et à Cuba; 2) d’étudier l’interaction entre cet apport et quatre polymorphismes nucléotidiques (SNP) identifiés dans la plupart des études d’association pangénomiques (GWAS) comme associés au risque de CDT, ainsi qu’avec les facteurs de risque environnementaux connus ; et 3) d’évaluer l’intérêt du sélénium présent dans les ongles comme un bio-marqueur potentiel du risque de CDT.Matériel et Méthodes: La régression logistique conditionnelle a été utilisée pour analyser la relation entre l'apport alimentaire en iode et le risque de CDT d’abord dans l’étude Cuba incluant 203 cas et 212 témoins, puis dans l’ensemble des cinq études incluant au total 2162 cas et 2571 témoins. Les questionnaires alimentaires de ces cinq études étaient dérivés de ceux de l’étude de cohorte E3N. Les mesures de l’iode et du sélénium dans les aliments traditionnels polynésiens et cubains avaient été réalisées spécialement pour cette étude. Quatre SNPs avaient été génotypés, dont deux sur le gène FOXE1, un sur le gène ATM et un autre près du gène NKX2-1. Les mesures de l’iode, du sélénium et des autres oligoéléments métalliques avaient été réalisées dans les ongles des sujets de l’étude Polynésie Française.Résultats: Il n’a pas été observée, une association significative entre l’apport alimentaire en iode et le risque de CDT dans l’étude réalisée à Cuba. Dans l'ensemble des cinq études, la majorité des cas et des témoins ont été considérée comme présentant une carence légère en iode selon la classification du Réseau Mondial d'Iode (IGN). Bien que le risque de CDT ne soit pas lié à l'apport alimentaire en iode, ce risque était significativement réduit avec l’augmentation de la consommation de poisson, ceci de manière plus importante dans l'étude réalisée à Cuba que dans les autres. En outre, une augmentation de l’apport alimentaire en iode a été significativement associée à une diminution du risque de CDT uniquement dans l’étude réalisée en Polynésie Française et chez les Polynésiens. Une augmentation significative du risque de CDT associée au nombre de l'allèle mineur (A) du SNP rs965513 près de FOXE1 parmi les sujets qui ont consommé moins d'iode que la médiane dans l'étude réalisée à Cuba. Pour les femmes qui ont eu un nombre de grossesses élevé et qui étaient déficitaires en iode, l'augmentation de l'apport alimentaire en iode réduisait leur risque de CDT. Par ailleurs, il n’a pas été possible de mettre en évidence un intérêt du sélénium dans les ongles comme bio-marqueur prédictif du risque de CDT
Context: Iodine is a trace element derived from food. In endemic goiter areas characterized by dietary iodine deficiency, it is established that the incidence of goiter and differentiated thyroid cancers (DTC) of follicular type is higher than elsewhere. On the other hand, the influence of dietary iodine intake in the risk of papillary thyroid cancer which currently representing more than 80% of DTCs in most countries, has not achieved a consensus. It appears, however, that this incidence is higher in the Pacific islands than elsewhere. In addition, the redox protection properties of selenium could protect the thyroid gland and help to maintain the production of thyroid hormones, but few studies evaluated the relationship between selenium intake and DTC.Objectives: The general objective of this thesis was to explore the relationship between dietary iodine intake and DTC risk. More specifically, it was 1) to study the relationship between dietary iodine intake and the risk of DTC in five case-control studies of Epi-Thyr consortium, carried out in New Caledonia, French Polynesia, Metropolitan France (two studies) and Cuba; 2) to investigate the interaction between this intake and four single-nucleotide polymorphisms (SNP) identified in most genome-wide association studies (GWAS) as associated with DTC risk, as well as the interaction with the well-established environmental risk factors; and 3) to evaluate the benefit of selenium present in fingernails as a potential bio-marker of DTC risk.Materials and Methods: Conditional logistic regression was used to analyze the relationship between dietary iodine intake and DTC risk first in the Cuba study including 203 cases and 212 controls, and then in the pooled analysis of the five studies including a total of 2162 cases and 2571 controls. The dietary questionnaires of these five studies were derived from those in the E3N cohort study. Measurements of iodine and selenium in traditional Polynesian and Cuban foods were specifically carried out for this pooled analysis. Four SNPs were genotyped, including two of FOXE1 gene, one of ATM gene and another near NKX2-1 gene. Measurements of iodine, selenium and other metal trace elements were made in the fingernails of the participants of the French Polynesia study.Results: There was no significant association between dietary iodine intake and DTC risk in the Cuba study. In the pooled analysis of the five studies, the majority of the cases and the controls was considered as being in mild dietary iodine deficiency according to the IGN classification. Although DTC risk was not found to be linked to dietary iodine intake, this risk significantly decreased with high fish consumption, this reduction in DTC risk per quartile of fish consumption was more important in the Cuba study than in the other studies. Additionally, higher dietary iodine intake significantly associated with lower DTC risk only in the French Polynesia study and in Polynesians. A strong increase in DTC risk associated with the number of the minor allele (A) of the SNP rs965513 near FOXE1, among participants who consumed less iodine than the median value in the Cuba study. For the women who had a high number of full term pregnancies and who were iodine deficient, increasing dietary iodine intake may reduce their risk of suffering from DTC. Moreover, it was not possible to demonstrate an interest in fingernail selenium as a biomarker that predicts DTC risk

Orientador: Vania dos Santos Nunes Nogueira
Abstract: Although being controversial, some services use Whole Body Imaging (WBI) with 131I prior to the ablative dose with this radiopharmaceutical in the treatment of differentiated thyroid cancers (DTC). Proponents of this approach argue for a better optimization of the ablative dose, and opponents argue that this WBI could lead to the "stunning effect" characterized by reduced tissue uptake of 131I in ablative dose treatment, thereby compromising treatment and prognosis of these individuals. Objective: To evaluate whether WBI with 131I, ablative pre-dose, interferes with the efficacy of the therapeutic dose of iodine as remission of the disease after total or near total thyroidectomy in individuals with DTC. Methodology: A systematic review of the literature was conducted in which randomized, non-randomized and observational studies were included in which the patients were in the late postoperative period of total or subtotal thyroidectomy due to one of the DCT and were assigned the diagnostic WBI with I131 before the ablative dose (intervention) or they performed WBI with 123I before the ablative dose, or non-performance of the diagnostic WBI (directly ablative dose with 131I) (control). The primary outcome was disease remission assessed by the ablative success rate at least six months after follow-up. Results: After performing the searches in the following electronic databases Embase (1980-25/04/2017), Pubmed (1966-25/04/2017), CENTRAL (Cochrane Controlled Trials Register) (04/2... (Complete abstract click electronic access below)
Resumo: Apesar de existirem controvérsias, alguns serviços utilizam a pesquisa de corpo inteiro (PCI) com 131I previamente a dose terapêutica com esse radionuclídeo no tratamento dos cânceres diferenciados da tiroide (CDT). Os defensores dessa conduta argumentam uma melhor otimização da dose ablativa, e os contrários afirmam que essa PCI poderia ocasionar o “efeito stunning”, caracterizado pela redução da captação tecidual do 131I no tratamento com a dose ablativa, comprometendo com isso o tratamento e o prognóstico desses indivíduos. Objetivo: avaliar se a PCI com 131I, pré-dose ablativa, interfere na eficácia da dose terapêutica de iodo quanto a remissão da doença após a tireoidectomia total ou quase total em indivíduos com CDT. Metodologia: foi realizada uma revisão sistemática da literatura na qual foram incluídos estudos controlados randomizados, não randomizados e observacionais, nos quais os pacientes estavam em pós-operatório de tireoidectomia total ou subtotal devido um dos CDT, e foram alocados a um dos dois grupos: PCI diagnóstica com 131I realizada antes da dose terapêutica com I131(intervenção), ou a PCI realizada com 123I antes da dose ablativa, ou não realização da PCI diagnóstica antes da dose terapêutica (ambos controle). O desfecho principal foi a remissão da doença avaliada pela taxa de sucesso ablativo em pelo menos seis meses de seguimento. Resultados: depois de realizadas as pesquisas nas bases eletrônicas Embase (1980–25/04/2017), Pubmed (1966–25/04/2017), CENT... (Resumo completo, clicar acesso eletrônico abaixo)
Mestre

碩士
國立臺灣大學
護理學研究所
107
The purposes of this study were to (1) explore the level of symptom severity, body image changes, fear cancer recurrence (FCR), and supportive care need; and (2) the relationship between care needs and disease/ treatments and above mentioned factors in Differentiated Thyroid Cancer (DTC) patients within three year post surgery. A cross-sectional design with consecutive sampling was conducted to recruit DTC patients in one medical center in Northern Taiwan. Two research nurses assessed for patients’ Symptom Severity, Body Image, Fear of Cancer Recurrence, (4) Supportive Care Needs. The descriptive statistics, Mann-Whitney U Test, Kruskal–Wallis H test, Spearman''s rank correlation, and logistic regression were applied for data analysis. A total of 150 participants were recruited. The results showed that (1) in general, DTC patients experienced mild symptom severity; (2) having mild body image change and majority of patients had mild levels of FCR; (3) patients care needs as its descending order are system and information needs, nutritional and symptom requirement needs and psychological needs; (4) overall care needs were associated to gender, stage of cancer, higher symptom severity, higher body image score, and higher FCR. Symptoms severity and FCR are the two most robust factors to predict the overall care needs based on the logistic regression. Providing appropriate care through needs assessments are strongly suggested to decrease the unmet care needs in DTC patients.

The incidence of differentiated thyroid cancer (DTC) is rising, but controversy exists in many aspects of its treatment. This study described the change in incidence of DTC in Ontario, variations in management including extent of thyroidectomy and the influence of provider volume, and the impact of these parameters on recurrence and thyroid cancer-specific death (TCSD). A population-based study identified all new cases of DTC between 1992-2007. The incidence of DTC increased dramatically (annual percentage change 7.6%). Linkage to administrative databases revealed that extent of thyroidectomy is influenced by various factors including patient gender, age, year of diagnosis, surgeon specialty, and hospital setting, but not provider volume. Total thyroidectomy is associated with a lower recurrence rate. There is a significant association between provider volume and recurrence, with lower volume surgeons having a higher recurrence risk. Extent of thyroidectomy and provider volume did not influence TCSD. Such variations in management may lead to disparities in health outcomes.

碩士
高雄醫學大學
醫學研究所碩士班
96
Objectives/Hypothesis DNA base excision repair (BER) pathway has been shown to be related with carcinogenesis. We hypothesized that functional polymorphisms of five BER genes, hOGG1 (human oxoguanine glycosylase 1), MBD4 (methyl-CpG binding domain protein 4), XRCC1 (X-ray repair cross complementing group 1), APE1 (apurinic/apyrymidinic endonuclease/redox effector-1) and ADPRT (adenosine diphosphate ribosyl transferase) confer a risk for differentiated thyroid carcinoma (DTC) and lymph node (LN) metastasis. Methods In a case–control study of 283 DTC cases and 293 controls, seven common non-synonymous single nucleotide polymorphisms (SNPs): Ser326Cys for hOGG1; Glu346Lys for MBD4; Arg194Trp, Arg280His, Arg399Gln for XRCC1; Asp148Glu for APE1, and Val762Ala for ADPRT were evaluated using the TaqMan 5'' nuclease assay. Hardy-Weinberg equilibrium (HWE) was tested for each SNP, and genetic effects were evaluated by the x2- test and multiple logistic regression. Results We found all seven SNPs were in HWE. The 194Trp/Trp genotype of XRCC1 showed a significantly increased risk of DTC (ORadj: 1.83, 95%CI:1.01-3.23, p=0.045), especially in LN metastasis cases (ORadj of 4.42, CI:1.95-9.98, p=0.003). The other six SNPs did not show significant results. Haplotype analysis of XRCC1 polymorphisms yielded a significant result (P= 0.04), especially in LN metastasis cases (P= 0.004). Moreover, we found that XRCC1-194Trp and ADPRT-762Ala variants collectively contribute to an increased risk of the disease and LN metastasis, with the combined variant homozygous genotypes exhibiting the highest 3.28-fold risk for DTC and 9.68-fold risk for DTC with LN metastasis. Conclusions We conclude that the XRCC1 polymorphisms, especially the 194Trp allele may have an effect on thyroid cancer development.This variant can interact with ADPRT-762Ala variant to further substantially increase susceptibility to the disease and regional LN metastasis. Identifying these risk genetic markers could provide more insight into the DTC pathogenesis and may also provide information to develop better therapeutic strategies.

碩士
高雄醫學大學
醫學研究所碩士班
96
Introduction: Although the exact etiology of differentiated thyroid cancer (DTC) is not well understood, exposure to radiation is considered as a risk factor. Radiation can cause direct DNA damage and the generation of reactive oxygen species (ROS). In the thyroid, ROS and free radicals can participate in physiological and pathological processes. The antioxidant enzymes such as glutathione peroxidase (GPX), especially GPX3, can lower down the oxidative stress in thyrocyte. We want to find the relationship between the genetic variants of GPX3 and differentiated thyroid cancer. Materials and Methods: This is a case-control study including 268 cases with histologically verified DTC (49 male, 219 female, mean age = 40.0±13.9) and 285 controls (158 male, 127 female, mean age = 45.2±13.3) in Departments of Otolaryngolgy or Endocrinology in Kaohsiung Medical University Hospital between October 2005 and December 2006. Six tSNPs (rs2070593, rs3763013, rs3792796, rs3805435, rs3828599, rs8177412) had been identified with rp2 of 0.8 or greater and MAF > 0.1 in the ethinic group of Chinese Han Beijing in HapMap project. We genotyped all samples for the selected tSNPs using the ABI PRISM 7500 sequence detection system (Applied Biosystems). Results: Genotyping success rate was ranged from 98.7% to 100%. The distribution of the allele frequency and genotype frequency of our six tSNPs in the case and control groups are in Hardy-Weinberg equilibrium. The overall analysis of the genotype and allele frequencies in each tSNP indicated that there is no significantly associated with differentiated thyroid cancer. The minor allele of SNP rs3805435 shows significant decreased in the group whose age more than 45 year-old. (p=0.016) The analyses of haplotype block 1 including SNP rs8177412 and SNP rs3763013 shows a significant increasing of the GC haplotype in case group whose age more than 45 year-old. (p=0.028) Conclusion: We found that homozygote AA of rs3805435 significantly increased a risk for differentiated thyroid cancer whose age more than 45 years old. GC haplotype in Block 1 including SNP rs8177412 and SNP rs3763013 has significant increasing in differentiated thyroid cancer.

Angiogenesis is crucial for cancer progression and its efficiency may affect disease evolution, and therefore clinical outcome. Given that cancer-related vessel formation relies on the host angiogenic machinery, individual genetic variability affecting physiological angiogenesis may impact on cancer prognosis. Function of angiogenesis-regulating genes may be affected from single nucleotide polymorphisms (SNPs) through the modulation of gene-expression. Prognostic stratification of differentiated thyroid cancer (DTC) is still suboptimal as no effective tools are available for identifying patients with persistent/recurrent disease after thyroid ablation. Our objective was to evaluate germline SNPs of VEGF-A, VEGFR-2, and PDGFR-α, as prognostic markers of clinical outcome in DTC. Multicenter retrospective study including consecutive DTC patients subjected to post-surgical follow-up. Eight angiogenesis-related SNPs were included in the analysis: -2578 C>A (rs699947), -460 T>C (rs833061), +405 G>C (rs2010963), and +936 C>T (rs3025039) for the VEGF-A gene; +1192 C>T (rs2305948) and +1719 T>A (rs1870377) for the VEGFR-2 gene; -1309 G>A (rs6554162) and -635 G>T (rs1800810) for the PDGFR-α gene. Genotyping was performed by means of TaqMan protocol. Prognostic outcome was categorized as persistent structural disease, recurrent structural disease, and no evidence of disease at last follow-up. Genotypes were analyzed as three-group categorical variable and according to the dominant and recessive model. Haplotype analysis was performed by means of the Haploview software. Positive (PPV) and negative (NPV) predictive values were calculated for identified genetic markers. Overall, 249 patients were included. No statistically significant results for any of the included SNPs were found at analysis of the overall population. Stratified analysis demonstrated that minor homozygous genotypes of VEGF-A -2578 C>A and -460 T>C (AA and CC, respectively) conferred protection against recurrent structural disease in AJCC/UICC stage I-II and ATA low-intermediate risk patients (p=0.035 with RR 0.17 and p=0.031 with RR 0.16, respectively). Haplotype analysis of VEGF-A SNPs identified 3 common haplotypes: the -2578C, -460T, +405C (CTC); the -2578A, -460C, +405G (ACG); the -2578C, -460T, +405G (CTG). ACG and CTG haplotypes were associated with the rate of structural recurrent disease in AJCC/UICC stage I-II (p=0.05 with OR 0.22 and 0.005 with OR 2.6, respectively) and ATA low-intermediate risk patients (p=0.036 with OR 0.51 and 0.039 with OR 1.93, respectively), exerting protective and deleterious effect, respectively. Analysis of combined-SNPs genotype found that the ACG homozygous genotype (ACG+/+) offered a protective effect against structural recurrence in both stage I-II (p=0.018, RR 0.2) and ATA low-intermediate (p=0.035, RR 0.17) risk patients, whereas the CTG homozygous genotype (CTG+/+) was significantly associated to higher rate of structural recurrence in stage I-II (p=0.018, RR=3.55), and was slightly deleterious also in ATA low-intermediate risk (p=0.079, RR=2.59) subjects. The ACG+/+ genotype retained its prognostic effect in ATA low-intermediate risk patients after adjustment for tumour size and multifocality. Both ACG+/+ and CTG+/+ genotypes showed high NPV, but only CTG+/+ revealed acceptable PPV for structural recurrent disease (42.8% and 33.3% in stage I-II and ATA low-intermediate risk patients, respectively). Analysis of germline VEGF-A SNPs may refine risk stratification of DTC with “early” disease by providing stable and easily accessible prognostic markers. The validation of these markers may facilitate clinical decision-making, which is still challenging regarding several therapeutic aspects. The relevance of VEGF-A genetic variability in this group of DTC may provide rationale for considering VEGF-A targeted therapies as a possible tool for the treatment of subjects harbouring the disease recurrence risk genotype.

Trabalho Final do Mestrado Integrado em Medicina apresentado à Faculdade de Medicina
Introduction: Tyrosine kinase inhibitors (TKI) are the main therapeutic alternative for differentiated thyroid carcinomas refractory to radioiodine (131I), progressive and metastatic. Few data are available on the efficacy and safety of sequentially using a second drug of this class.Clinical case: A patient submitted to total thyroidectomy in 2012 for papillary carcinoma measuring 9 cm, with extrathyroidal extension, venolymphatic invasion, lymph node metastasis (pT3N1bMx;R0;LVI) and neoplastic thromboembosis in the internal jugular is presented. The post-surgical evaluation revealed a bulky right tumour mass in the right lateral compartment, measuring 4,8x2,8cm, together with a lymph node metastasis with 2,3x1,6cm; the serum thyroglobulin value was 4969ng/mL.The patient underwent two cycles of 131I therapy (total activity =233mCi); the whole-body scintigraphy showed residual thyroid tissue, without uptake in the tumour lesions. In this context, the patient underwent cervical radiotherapy.The disease was stable during six months, becoming progressive afterwards, and the patient initiate Sorafenib in 2014.After four months of therapy, both the size of the lymph node metastases and thyroglobulin levels were reduced (70,141→39,218ng/mL). Subsequently, the disease progressed and, in 2017, the patient had dedifferentiated disease in the thyroid bed, extensive cervical and mediastinal-hilar lymph node metastases, and multiple lung metastases; thyroglobulin =159,680ng/mL.In this scenario, Sorafenib was withdrawn and the patient started Lenvatinib.During the first month on Lenvatinib, there was a biochemical response, with reduction of thyroglobulin (141,330→50,100ng/mL). However, worsening of asthenia and anorexia and elevation of blood pressure led to dose reduction and, subsequently, the patient was diagnosed with pneumonia and liver toxicity, which led to Lenvatinib suspension. The imaging study revealed dimensional stability of the lesions.Conclusion: This case illustrates the problem of the sequential use of TKIs. Despite the potential therapeutic efficacy, serious side effects should always be considered in patients who, despite progressive disease, may remain virtually asymptomatic.
Introdução: Os inibidores de cinases de tirosina (TKI) constituem a principal alternativa terapêutica para os carcinomas diferenciados da tiroide refratários ao Iodo 131 (131I), progressivos e metastáticos. Existem poucos dados sobre a eficácia e segurança de utilizar sequencialmente um segundo fármaco desta classe. Caso clínico: Apresenta-se o caso de uma doente submetida a tiroidectomia total em 2012 por carcinoma papilar medindo 9 cm, com extensão extratiroideia, invasão venolinfática, metastização ganglionar linfática (pT3N1bMx;R0;LVI) e tromboembolia neoplásica na jugular interna. A avaliação pós-cirúrgica revelou uma massa tumoral laterocervical direita, com 4,8x2,8cm e uma adenopatia jugulocarotídea com 2,3x1,6cm; o valor de tireoglobulina sérica era de 4969ng/mL.A doente foi submetida a duas terapêuticas com 131I (atividade total =233mCi); as cintigrafias corporais pós-terapêutica mostraram tecido tiroideu residual, sem captação nas lesões tumorais. Neste contexto, a doente foi submetida a radioterapia cervical.Durante seis meses ocorreu estabilização da doença, mas posteriormente houve progressão, pelo que em 2014 iniciou Sorafenib.Após quatro meses de terapêutica, registou-se redução das dimensões das adenopatias e dos níveis de tireoglobulina (70.141→39.218 ng/mL). Posteriormente a doença progrediu e, em 2017, a doente apresentava doença desdiferenciada na loca tiroideia, acompanhada de extensa metastização ganglionar cervical e mediastino-hilar, assim como múltiplas metástases pulmonares; tireoglobulina =159.680ng/mL.Neste cenário o Sorafenib foi suspenso e a doente iniciou Lenvatinib. Durante o primeiro mês houve resposta bioquímica relevante, com redução da tireoglobulina (141.330→50.100 ng/mL). No entanto, ocorreu agravamento da astenia, e anorexia e elevação da tensão arterial levando a redução da dose e, posteriormente, pneumonia com hepatite iatrogénica, tendo o Lenvatinib sido suspenso. O estudo imagiológico revelou estabilidade dimensional das lesões.Conclusão: Este caso ilustra a problemática da utilização sequencial de TKIs. Se por um lado poderá haver eficácia terapêutica, terá sempre de ser considerada a possibilidade de efeitos secundários graves em doentes que, apesar da doença progressiva, podem permanecer praticamente assintomáticos.

Θεωρητικό υπόβαθρο: Το οξειδωτικό στρες (ΟΣ) ορίζεται ως το παθολογικό αποτέλεσμα που προκύπτει από τη διαταραχή της ισορροπίας των κυτταρικών συγκεντρώσεων των οξειδωτικών, δραστικών ενώσεων και των αντιοξειδωτικών μορίων. Εκτός από τη βλάβη που υπόκεινται οι πρωτεΐνες και τα λιπίδια, το ΟΣ μπορεί επίσης να προκαλέσει μεταλλάξεις και επιγενετικές μεταβολές καταστρέφοντας τόσο το DNA όσο και τις πρωτεΐνες που τροποποιούν τη χρωματίνη. Παρ' όλα αυτά, στα θυρεοειδικά θυλακικά κύτταρα παράγονται σε καθημερινή βάση υψηλές ποσότητες υπεροξειδίου του υδρογόνου (H2O2), οξειδωτικής ουσίας απαραίτητης για την πραγματοποίηση της θυρεοειδικής ορμονογένεσης. Δεδομένου ότι ένα ελάχιστο ποσό οξειδωτικού φορτίου αποτελεί προϋπόθεση αφ’ενός για τη φυσιολογική λειτουργία των θυλακικών κυττάρων και αφ’ετέρου για την ανάπτυξη του θυρεοειδούς αδένα, πρόσφατα αποδείχτηκε ότι ο θυρεοειδής αδένας παρουσιάζει αυξημένη αμυντική ανταπόκριση έναντι του ΟΣ. Ωστόσο, οι ακριβείς μηχανισμοί με τους οποίους τα θυλακικά κύτταρα αντιλαμβάνονται και απαντούν στο ΟΣ παραμένουν ασαφείς. Ο NFE2-related factor 2 (Nrf2), ο οποίος κωδικοποιείται από το γονίδιο NFE2L2, είναι ένας μεταγραφικός παράγοντας ο οποίος απαντά σε σήματα κυτταρικού στρες και ανταποκρίνεται επιδρώντας στη μεταγραφή γονιδίων σε διάφορους τύπους ιστών. Σε βασικές συνθήκες, ο Nrf2 οδηγείται σε πρωτεασωματική αποικοδόμηση μέσω του κυτταροπλασματικού του αναστολέα, Keap1, ενώ σε συνθήκες ΟΣ, η αποικοδόμηση του Nrf2 δεν είναι δυνατή και ο Nrf2 εισέρχεται στον πυρήνα ώστε να ενεργοποιήσει τη μεταγραφή αντιοξειδωτικών γονιδίων όπως του γονιδίου Nqo1. Καθώς η οξειδοαναγωγική ομοιοστασία κατέχει κεντρικό ρόλο στην φυσιολογία του θυρεοειδούς αδένα και ο Nrf2 πρόσφατα χαρακτηρίσθηκε ως μεσολαβητής στην αντίσταση θυρεοειδικών καρκινικών κυτταρικών σειρών σε πρωτεασωμικούς αναστολείς, το αντιοξειδωτικό μονοπάτι Nrf2 μπορεί να θεωρηθεί ως εξαιρετικός υποψήφιος της διαμεσολάβησης της απόκρισης του θυρεοειδούς αδένα στο ΟΣ. Παρ 'όλα αυτά, ο ρόλος του μονοπατιού Nrf2 στον ανθρώπινο θυρεοειδικό καρκίνο παραμένει άγνωστος. Στόχος: Στόχοι της παρούσας μελέτης ήταν η εκτίμηση της δραστηριότητας του μονοπατιού Νrf2 στο διαφοροποιημένο καρκίνωμα του θυρεοειδούς αδένα και η διερεύνηση σωματικών μεταλλάξεων των γονιδίων NFE2L2 και Keap1. Yλικά και Μέθοδοι Ασθενείς: Στη μελέτη συμμετείχαν 90 περιστατικά εκ των οποίων τα 42 αφορούσαν θηλώδη καρκινώματα (papillary thyroid carcinomas, PTCs), τα 6 θυλακιώδη καρκινώματα (follicular thyroid carcinomas, FTCs) και τα υπόλοιπα 42 καλοήθεις όγκους (24 αδενώματα και 18 οζώδης υπερπλασία). Κυτταρικές σειρές: Στα πλαίσια της παρούσας μελέτης χρησιμοποιήθηκαν κυτταρικές σειρές PTC (K1, TPC-1, XTC-1), κυτταρική σειρά φτωχά διαφοροποιημένου PTC (T243), κυτταρικές σειρές αδιαφοροποίητου καρκινώματος (C643, 8505C, Hth74) και τέλος κυτταρικές σειρές αναπλαστικού καρκινώματος (T235 , T241, T238). Μέθοδοι: Αναδρομική ανοσοϊστοχημική ανάλυση δειγμάτων PTC και FTC, παρακείμενου φυσιολογικού ιστού και καλοηθών βλαβών. Ανάλυση αλληλουχίας DNA των κυτταρικών σειρών και PTC δειγμάτων. Κύριες μετρήσεις και υπολογισμοί: Αξιολογήθηκε η ένταση της ανοσοαντίδρασης των δειγμάτων των ιστών σε αντισώματα για τα Nrf2, Nqo1, Keap1 και 4-HNE. Μελετήθηκε η αλληλουχία του εξονίου 2 του γονιδίου NFE2L2 καθώς και του γονιδίου Keap1. Αποτελέσματα: O μεταγραφικός παράγοντας Nrf2 καθώς και ο στόχος του, η πρωτεΐνη Nqo1 ήταν μη ανιχνεύσιμα σε φυσιολογικό ιστό θυρεοειδούς αδένα. Τα επίπεδά τους ήταν σημαντικά υψηλότερα στα PTC δείγματα από ό,τι στα δείγματα καλοηθών βλαβών. Η έκφραση του Keap1 εμφάνισε διακύμανση στα δείγματα PTC με τα επίπεδά του να μην εμφανίζουν συσχέτιση με τα αντίστοιχα του Nrf2, ενάντια στη θεωρία πως τα μειωμένα επίπεδα του Κeap1 συνιστούν μηχανισμό ενεργοποίησης του Nrf2. Ο δείκτης ΟΣ, 4-HNE βρέθηκε αυξημένος στη πλειοψηφία των δειγμάτων PTC σε σχέση με το φυσιολογικό ιστό αναδεικνύοντας την ύπαρξη αυξημένου ΟΣ στο PTC. Επιπλέον, όσον αφορά τα δείγματα FTC, ο μεταγραφικός παράγοντας Nrf2 και η πρωτεΐνη Nqo1 ήταν ανιχνεύσιμα σε όλα τα δείγματα, ενώ τα επίπεδα του 4-ΗΝΕ ήταν αυξημένα. Όσον αφορά την ανάλυση αλληλουχίας DNA στις καρκινικές σειρές και σε 11 δείγματα PTC με υψηλή έκφραση Nrf2, καμία μετάλλαξη δεν ανευρέθηκε στο εξόνιο 2 του γονιδίου NFE2L2 και στο γονίδιο Keap1. Συμπεράσματα: Τα αποτελέσματα της μελέτης μας σε συνδυασμό με περαιτέρω μελέτες από το εργαστήριο Ενδοκρινολογίας και Ανατομικής του Πανεπιστημίου Πατρών καθώς και από το BC κέντρο έρευνας καρκίνου (Vancouver, Canada) αποδεικνύουν ότι το μονοπάτι Nrf2 ενεργοποιείται σε PTC και κατέχει ρυθμιστικό ρόλο στην αντιοξειδωτική απόκριση και τη βιωσιμότητα των θυρεοειδικών καρκινικών κυττάρων. Συνεπώς, αναδεικνύεται το Nrf2 μονοπάτι ως νέο “σήμα κατατεθέν” του PTC. Παρά το γεγονός ότι δεν ήταν δυνατή η πραγματοποίηση στατιστικών συσχετίσεων στη μελέτη του FTC λόγω του περιορισμένου αριθμού δειγμάτων, το μονοπάτι Nrf2 φαίνεται να ενεργοποιείται επίσης στο FTC. Η σταθερή ενεργοποίηση του Nrf2 στο PTC και ενδεχομένως στο FTC δίνει το έναυσμα για περαιτέρω διερεύνηση του μονοπατιού αυτού σε όλα τα είδη θυρεοειδικού καρκίνου καθώς και της πιθανής διαγνωστικής, προγνωστικής, και/ή θεραπευτικής χρησιμότητας του μονοπατιού στο διαφοροποιημένο καρκίνο του θυρεοειδούς αδένα.
Scientific background: Oxidative stress (ΟS) is experienced by cells when pro-oxidant and electrophilic reactive species overwhelm the cell’s antioxidant and detoxification proteins. In addition to causing protein and lipid damage, oxidative stress can cause mutations and epigenetic perturbation by damaging DNA and proteins that modify chromatin. Nevertheless, in thyrocytes a daily basis high amounts of the oxidant hydrogen hyperoxide (H2O2) was generated due to the fact that H2O2 is a reactive oxygen species required for thyroid hormonogenesis. A minimal oxidative load is a prerequisite for normal thyroid cell function and development and it was recently shown that the thyroid has increased capacity for defending itself against OS. However, precise mechanisms by which thyrocytes sense and respond to OS remain obscure. NFE2-related factor 2 (Nrf2), encoded by NFE2L2 gene, is a transcription factor that integrates cellular stress signals and responds by directing transcriptional program in various tissues. In basal conditions, Nrf2 is targeted for proteasomal degradation by its cytoplasmic inhibitor, Kelch-like ECH-associated protein 1 (Keap1), while in oxidative stress Nrf2 degradation is abolished and Nrf2 accumulates in the nucleus where it transactivates protective genes such as NAD(P)H dehydrogonase quinone 1 (Nqo1). As redox homeostasis plays a principal role in thyroid gland’s physiology, and Nrf2 has recently been characterised as mediator of thyroid cancer cell lines’ resistance to proteasome inhibitors, the Nrf2 antioxidant pathway seems to be an excellent candidate for mediating the antioxidant response of the thyroid gland. Nevertheless, the activity status of the Nrf2 pathway in human thyroid cancer remains unknown. Objective: The aims of this study were to assess the activity status of the Nrf2 pathway in differentiated thyroid carcinoma and investigate somatic mutations in NFE2L2 and Keap1 genes. Μethods and Materials Patients: The study included 90 individual samples; 42 papillarz thyroid carcinomas (PTCs), 6 follicular thyroid carcinomas (FTCs) and 42 benign lesions (24 adenomas and 18 nodular hyperplasias). Cell lines: Ten thyroid cell lines are used for this study: The PTC cell lines, K1, TPC-1 and XTC-1; the poorly differentiated PTC cell line, T243; the undifferentiated carcinoma cell lines, C643, 8505C and Hth74; and the anaplastic carcinoma cell lines, T235, T241 and T238. Methods: We conducted retrospective immunohistochemical analyses of PTC and FTC specimens, adjacent normal tissue, and benign lesions; DNA sequencing in cell lines and PTC samples. Main Outcome Measures: We assessed the abundance of Nrf2, Nqo1, Keap1, and 4HNE; and the sequence of NFE2L2 gene’s exon 2 and of KEAP1 gene. Results: Nrf2 and its target Nqo1 were undetectable in normal tissue; their levels were significantly higher in PTC than in benign lesions. The Nrf2 inhibitor, Keap1 was variably abundant in PTC, and its levels did not correlate with Nrf2, arguing against decreased levels as the mechanism for Nrf2 activation. The oxidized lipid 4HNE was more abundant in PTC than normal tissue indicating oxidative stress. In addition, as far as FTC samples are concerned, Nrf2 and Nqo1 were detectable in all samples as well as the levels of 4-HNE were significantly high. No mutations were detectable in exon 2 of NFE2L2 gene and in Keap1 gene. Conclusions: Our study’s results supported by further studies in laboratories of Endocrinology and Anatomy at University of Patras and BC Cancer Research Center (Vancouver, Canada) demonstrate that the Nrf2 pathway is commonly activated in PTC and that it regulates antioxidant responses and viability of cancer cells. Thus, Nrf2 is highlighted as a new hallmark of PTC. Although, statistic correlations were not possible in FTC samples’ study because of small sample size, the Nrf2 pathway seems to be also activated in FTC. The high activity of Nrf2 in PTC and possibly in FTC warrants further exploration of this pathway’s potential diagnostic, prognostic, and/or therapeutic utility in differentiated thyroid carcinoma.