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Un modello multivariato integrato di previsione del rischio neoplastico dei noduli della tiroide
No full textRiassunto
Obiettivo: la diagnosi di natura di un nodulo della tiroide è ancora oggi un problema non
completamente risolto e spesso vengono eseguiti interventi a solo scopo di conferma istologica.
Lo studio si propone di definire un modello integrato predittivo del rischio neoplastico per un
nodulo tiroideo: Tale modello può essere complementare all’attuale approccio sequenziale di
attività diagnostiche, governato da criteri mono-dimensionali.
Materiali: sono stati raccolti i dati clinici, ecografici e citologici preoperatori di 168 pazienti
consecutivi (per un totale di 197 noduli studiati), operati successivamente di tiroidectomia totale. I
dati sono stati analizzati con statistica monovariata e quindi integrati in un modello statistico
multivariato. Sono stati esclusi pazienti con referto citologico inadeguato (classe Th 1 secondo la
British Thyroid Ass.) o con diagnosi citologica certa di neoplasia (classe Th 5).
Risultati: sono risultate variabili predittive indipendenti di maggior valore la anisonucleosi, la
presenza di atipie e di proliferazione follicolare nell’esame citologico; la presenza di calcificazioni
interne al nodulo e l’unicità del nodulo stesso come caratteri ecografici.
Conclusioni: è stato possibile integrare in un unico modello predittivo di rischio a cinque elementi i
caratteri derivanti dall’ecografia e dalla citologia su FNA. Tale modello può essere la base per
ottenere un sistema di punteggio da affiancare alla strategia di semplice algoritmo sequenziale
raccomandata dalle linee guida attuali.
Summary
Objective: the diagnosis of nature of a thyroid nodule is still an unresolved problem and often
patients undergo surgery just to confirm an histological diagnosis. This study is aimed to define an
integrated model to predict the risk of malignancy for a thyroid nodule. This model should
complement the presently preferred approach, based on a sequential diagnostic workup ruled by
mono-dimensional criteria.
Materials: data from clinical exam, ultrasound and cytology were collected in the preoperative
period from 168 consecutive patients (for a total number of 197 considered nodules), who then
underwent total thyroidectomy. Data were analysed by monovariate statistics and then integrated in
a multivariate statistical model. Patients with an inadequate cytology (Th 1class, according to la
British Thyroid Ass.) or with a definite cytological diagnosis of malignancy (Th 5class) were
excluded.
Results: anisonucleosis, the presence of atipia and follicular proliferation resulted as independent
significant criteria for cytology; the presence of calcifications inside a nodule and the condition of
unique nodule were the ultrasonographic most significant characters.
Conclusions: it has been possible to integrate in a unique predictive model of risk with five
elements the information deriving from ultrasound and cytology. This model can be the starting
point to obtain a scoring system to improve the strategy of simple sequential algorithm
recommended by the present guidelines.
Introduzione
La diagnosi di natura di un nodulo della tiroide è ancora oggi un problema non completamente
risolto e poiché, nonostante l’alta prevalenza dei noduli della tiroide, solo in una piccola percentuale
di casi essi sono maligni, spesso vengono eseguiti interventi a solo scopo di conferma istologica.
Le più recenti linee guida (1, 2, 3) raccomandano un flusso sequenziale di attività diagnostiche,
governato da criteri mono-dimensionali (anamnesi-esame obiettivo ecografia FNA) e non
sembrano esistere in letteratura tentativi di costruire sistemi di punteggio di rischio, specie per
quella tipologia di noduli tiroidei con caratteristiche ecografie sospette o con citologia di tipo
“lesione follicolare”. Lo scopo dello studio è quello di confermare il valore diagnostico di alcune
delle caratteristiche della citologia e dell’ecografia citate in letteratura come predittive di malignità
(4, 5, 6) e integrarle in un unico modello statistico multivariato predittivo del rischio di neoplastico
Survivin and cyclin D1 are jointly expressed in thyroid papillary carcinoma and microcarcinoma
No full textIn order to define more effective predictive markers for clinical management and prognosis, we evaluated the expression of cyclin D1 and survivin in large papillary thyroid carcinoma (LPTC) and microcarcinoma (PTM). Sixty-seven patients operated for papillary carcinoma (36 of which with PTM) were considered. Immunochemistry for cyclin D1 and survivin was performed in samples from tumor mass and nodal metastases. There were not significant differences between LPTC and PTM as to patients personal data, TNM or MACIS staging, nodal invasion and multi-focality, while capsular invasion was significantly more frequent in LPTC. Cyclin D1 and survivin were expressed at a very high rate and almost to the same extent in LPTC and PTM, both in tumoral mass and in nodal metastases. Survivin showed only cytoplasmic expression. Cyclin D1 and survivin over-expression are probably early events in tumorigenesis of thyroid papillary carcinoma but their full role in the process of tumor progression and their clinical value are still to be investigated
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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