1,720,999 research outputs found
[Lung cancer screening in high-risk subjects: early detection with LDCT and risk stratification using miRNA-based blood test]
No full textLung cancer still remains a high mortality disease in the face of developments in diagnostic and therapeutic methods that occurred in the last 20 years. The analysis of the experiences from the first studies - in which chest X-ray (CXR) was adopted, associated or not with sputum cytology - has failed to show a reduction in lung cancer specific mortality. Subsequent screening studies that have introduced the use of low-dose computed tomography (LDCT) have revealed a large number of early-stage lung cancers, thus potentially curable; however, this has not allowed us to demonstrate a decrease in lung cancer-specific mortality. With the results of the American study National Lung ScreeningTrial (NLST), published in 2011, for the first time a lung cancer-specific mortality reduction by 20% thanks to the use of LDCT compared to RXT, was highlighted. However, a false positive rate of 96.4% was also described with an overdiagnosis that can be up to 78.9%for bronchioalveolar lung cancer. Due to the high sensitivity of LDCT, able to identify a non-calcified pulmonary nodule in one subject on two, it becomes necessary to avail instruments to more accurately identify suspicious nodules. Until some time ago, the possible use of lung tumour markers was not viable in view of the poor organ specificity. The study and development was, then, pushed to organ- and tissue-specific markers such as microRNA (miRNA), noncoding RNA sequences involved in many processes and expression of oncogenic activity of the microenvironment. The use of biomarkers such as circulating miRNA implemented in LDCT screening has highlighted a reduction of 5 times for the rate of false positives, going from 19.4% to 3.7%, with a sensitivity of 87%, a specificity of 81%, and a negative predictive value of 99%. The need to appropriately use the available resources commensurate with the disease to treat will push more and more towards the implementation of LDCT biomarkers based screenings, stable and easily reproducible, as circulating miRNAs, obviating to problems such as false positives, unnecessary procedures of invasive surgery for benign lesions, and optimizing the cost benefit ratios.The development of new specific biomarkers appears to offer new promising prospects
MRI based radiomics in nasopharyngeal cancer: systematic review and perspectives using Radiomic Quality Score (RQS) assessment
Get PDFBackground
MRI based radiomics has the potential to better define tumor biology compared to qualitative MRI assessment and support decisions in patients affected by nasopharyngeal carcinoma. Aim of this review was to systematically evaluate the methodological quality of studies using MRI- radiomics for nasopharyngeal cancer patient evaluation.
Methods
A systematic search was performed in PUBMED, WEB OF SCIENCE and SCOPUS using “MRI, magnetic resonance imaging, radiomic, texture analysis, nasopharyngeal carcinoma, nasopharyngeal cancer” in all possible combinations. The methodological quality of study included ( = 24) was evaluated according to the RQS (Radiomic quality score). Subgroup, for journal type (imaging/clinical) and biomarker (prognostic/predictive), and correlation, between RQS and journal Impact Factor, analyses were performed. Mann-Whitney U test and Spearman’s correlation were performed. P value < .05 were defined as statistically significant.
Results
Overall, no studies reported a phantom study or a test re-test for assessing stability in image, biological correlation or open science data. Only 8% of them included external validation. Almost half of articles (45%) performed multivariable analysis with non-radiomics features. Only 1 study was prospective (4%). The mean RQS was 7.5 ± 5.4. No significant differences were detected between articles published in clinical/imaging journal and between studies with a predictive or prognostic biomarker. No significant correlation was found between total RQS and Impact Factor of the year of publication (p always > 0.05).
Conclusions
Radiomic articles in nasopharyngeal cancer are mostly of low methodological quality. The greatest limitations are the lack of external validation, biological correlates, prospective design and open science
The impact of radiomics for human papillomavirus status prediction in oropharyngeal cancer: systematic review and radiomics quality score assessment
No full textHuman papillomavirus (HPV) status assessment is crucial for decision making in oropharyngeal cancer patients. In last years, several articles have been published investigating the possible role of radiomics in distinguishing HPV-positive from HPV-negative neoplasms. Aim of this review was to perform a systematic quality assessment of radiomic studies published on this topic. Radiomics studies on HPV status prediction in oropharyngeal cancer patients were selected. The Radiomic Quality Score (RQS) was assessed by three readers to evaluate their methodological quality. In addition, possible correlations between RQS% and journal type, year of publication, impact factor, and journal rank were investigated. After the literature search, 19 articles were selected whose RQS median was 33% (range 0–42%). Overall, 16/19 studies included a well-documented imaging protocol, 13/19 demonstrated phenotypic differences, and all were compared with the current gold standard. No study included a public protocol, phantom study, or imaging at multiple time points. More than half (13/19) included feature selection and only 2 were comprehensive of non-radiomic features. Mean RQS was significantly higher in clinical journals. Radiomics has been proposed for oropharyngeal cancer HPV status assessment, with promising results. However, these are supported by low methodological quality investigations. Further studies with higher methodological quality, appropriate standardization, and greater attention to validation are necessary prior to clinical adoption
Low-dose computed tomography for lung cancer screening: comparison of performance between annual and biennial screen
No full textObjectives: To compare the performance metrics of two different strategies of lung cancer screening by low-dose computed tomography (LDCT), namely, annual (LDCT1) or biennial (LDCT2) screen. Methods: Recall rate, detection rate, interval cancers, sensitivity, specificity, positive and negative predictive values (PPV and NPV, respectively) were compared between LDCT1 and LDCT2 arms of the MILD trial over the first seven (T0-T6; median follow-up 7.3 years) and four rounds (T0-T3; median follow-up 7.3 years), respectively. Results: 1152 LDCT1 and 1151 LDCT2 participants underwent a total of 6893 and 4715 LDCT scans, respectively. The overall recall rate was higher in LDCT2 arm (6.97 %) than in LDCT1 arm (5.81 %) (p = 0.01), which was counterbalanced by the overall lower number of LDCT scans. No difference was observed for the overall detection rate (0.56 % in both arms). The two LDCT arms had similar specificity (99.2 % in both arms), sensitivity (73.5 %, in LDCT2 vs. 68.5 % in LDCT1, p = 0.62), PPV (42.4 %, in LDCT2, vs. 40.6 %, in LDCT1, p = 0.83) and NPV (99.8 %, in LDCT2 vs. 99.7 %, in LDCT1, p = 0.71). Conclusion: Biennial screen may save about one third of LDCT scans with similar performance indicators as compared to annual screening.Key Points: • Biennial LDCT screening may be as efficient as the annual screening.• Annual and biennial LDCT screening have similar frequency of interval lung cancers.• Biennial screening may save about one third of LDCT scans
A case of relapsing spinal atypical teratoid/rhabdoid tumor (AT/RT) responding to vinorelbine, cyclophosphamide, and celecoxib
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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
Developing a robust two-step machine learning multiclassification pipeline to predict primary site in head and neck carcinoma from lymph nodes
Full text linkThis study aimed to develop a robust multiclassification pipeline to determine the primary tumor location in patients with head and neck carcinoma of unknown primary using radiomics and machine learning techniques. The dataset included 400 head and neck cancer patients with primary tumor in oropharynx, OPC (n = 162), nasopharynx, NPC (n = 137), oral cavity, OC (n = 63), larynx and hypopharynx, HL (n = 38). Two radiomic-based multiclassification pipelines (P1 and P2) were developed. P1 consisted in a direct identification of the primary sites, whereas P2 was based on a two-step approach: in the first step, the number of classes was reduced by merging the two minority classes which were reclassified in the second step. Diverse correlation thresholds (0.75, 0.80, 0.85), feature selection methods (sequential forwards/backwards selection, sequential floating forward selection, neighborhood component analysis and minimum redundancy maximum relevance), and classification models (neural network, decision tree, naïve Bayes, bagged trees and support vector machine) were assessed. P2 outperformed P1, with the best results obtained with the support vector machine classifier including radiomic and clinical features (accuracies of 75.3 % (HL), 75.4 % (OC), 71.3 % (OPC), 92.9 % (NPC)). These results indicate that the two-step multiclassification pipeline integrating radiomics and clinical information is a promising approach to predict the tumor site of unknown primary
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
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