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As patient exposure to ionizing radiation from medical imaging and its risks are continuing issues, this study aimed to evaluate DNA damage and repair markers after myocardial perfusion single-photon emission computed tomography (MPS). Thirty-two patients undergoing Tc-99m sestamibi MPS were studied. Peripheral blood was collected before radiotracer injection at rest and 60-90 min after injection. The comet assay (single-cell gel electrophoresis) was performed with peripheral blood cells to detect DNA strand breaks. Three descriptors were evaluated: the percentage of DNA in the comet tail, tail length, and tail moment (the product of DNA tail percentage and tail length). Quantitative PCR (qPCR) was performed to evaluate the expression of five genes related to signaling pathways in response to DNA damage and repair (ATM, ATR, BRCA1, CDKN1A, and XPC). Mann-Whitney's test was employed for statistical analysis; p < 0.05 was considered significant. Mean Tc-99m sestamibi dose was 15.1 mCi. After radiotracer injection, comparing post-exposure to pre-exposure samples of each of the 32 patients, no statistically significant differences of the DNA percentage in the tail, tail length or tail moment were found. qPCR revealed increased expression of BRCA1 and XPC, without any significant difference regarding the other genes. No significant increase in DNA strand breaks was detected after a single radiotracer injection for MPS. There was activation of only two repair genes, which may indicate that, in the current patient sample, the effects of ionizing radiation on the DNA were not large enough to trigger intense repair responses, suggesting the absence of significant DNA damage.

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Given the frequent co-existence of an aggressive tumor and underlying chronic liver disease, the management of hepatocellular carcinoma (HCC) patients requires experienced multidisciplinary team discussion. Moreover, imaging plays a key role in the diagnosis, staging, restaging, and surveillance of HCC. Currently, imaging assessment of HCC entails the assessment of qualitative characteristics which are prone to inter-reader variability. Radiomics is an emerging field that extracts high-dimensional mineable quantitative features that cannot be assessed visually with the naked eye from medical imaging. The main potential applications of radiomic models in HCC are to predict histology, response to treatment, genetic signature, recurrence, and survival. Despite the encouraging results to date, there are challenges and limitations that need to be overcome before radiomics implementation in clinical practice. The purpose of this article is to review the main concepts and challenges pertaining to radiomics, and to review recent studies and potential applications of radiomics in HCC.

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PURPOSE: To evaluate an MRI-based radiomic texture classifier alone and combined with radiologist qualitative assessment in predicting pathological complete response (pCR) using restaging MRI with internal training and external validation. METHODS: Consecutive patients with locally advanced rectal cancer (LARC) who underwent neoadjuvant therapy followed by total mesorectal excision from March 2012 to February 2016 (Memorial Sloan Kettering Cancer Center/internal dataset, n = 114, 41% female, median age = 55) and July 2014 to October 2015 (Instituto do Câncer do Estado de São Paulo/external dataset, n = 50, 52% female, median age = 64.5) were retrospectively included. Two radiologists (R1, senior; R2, junior) independently evaluated restaging MRI, classifying patients (radiological complete response vs radiological partial response). Model A (n = 33 texture features), model B (n = 91 features including texture, shape, and edge features), and two combination models (model A + B + R1, model A + B + R2) were constructed. Pathology served as the reference standard for neoadjuvant treatment response. Comparison of the classifiers' AUCs on the external set was done using DeLong's test. RESULTS: Models A and B had similar discriminative ability (P = 0.3; Model B AUC = 83%, 95% CI 70%-97%). Combined models increased inter-reader agreement compared with radiologist-only interpretation (κ = 0.82, 95% CI 0.70-0.89 vs k = 0.25, 95% CI 0.11-0.61). The combined model slightly increased junior radiologist specificity, positive predictive value, and negative predictive values (93% vs 90%, 57% vs 50%, and 91% vs 90%, respectively). CONCLUSION: We developed and externally validated a combined model using radiomics and radiologist qualitative assessment, which improved inter-reader agreement and slightly increased the diagnostic performance of the junior radiologist in predicting pCR after neoadjuvant treatment in patients with LARC.

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Radiomics using rectal MRI radiomics has emerged as a promising approach in predicting pathological complete response. In this study, we present a typical pipeline of a radiomics analysis and review recent studies, exploring applications, development of radiomics methodologies and model construction in pCR prediction. Finally, we will offer our opinion about the future and discuss the next steps of rectal MRI radiomics for predicting pCR.

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OBJECTIVE: To investigate associations between genetic mutations and qualitative as well as quantitative features on MRI in rectal adenocarcinoma at primary staging. METHODS: In this retrospective study, patients with rectal adenocarcinoma, genome sequencing, and pretreatment rectal MRI were included. Statistical analysis was performed to evaluate associations between qualitative features obtained from subjective evaluation of rectal MRI and gene mutations as well as between quantitative textural features and gene mutations. For the qualitative evaluation, Fisher's Exact test was used to analyze categorical associations and Wilcoxon Rank Sum test was used for continuous clinical variables. For the quantitative evaluation, we performed manual segmentation of T2-weighted images for radiomics-based quantitative image analysis. Thirty-four texture features consisting of first order intensity histogram-based features (n = 4), second order Haralick textures (n = 5), and Gabor-edge based Haralick textures were computed at two different orientations. Consensus clustering was performed with 34 computed texture features using the K-means algorithm with Euclidean distance between the texture features. The clusters resulting from the algorithm were then used to enumerate the prevalence of gene mutations in those clusters. RESULTS: In 65 patients, 45 genes were mutated in more than 3/65 patients (5%) and were included in the statistical analysis. Regarding qualitative imaging features, on univariate analysis, tumor location was significantly associated with APC (p = 0.032) and RASA1 mutation (p = 0.032); CRM status was significantly associated with ATM mutation (p = 0.021); and lymph node metastasis was significantly associated with BRCA2 (p = 0.046) mutation. However, these associations were not significant after adjusting for multiple comparisons. Regarding quantitative imaging features, Cluster C1 had tumors with higher mean Gabor edge intensity compared with cluster C2 (θ = 0°, p = 0.018; θ = 45°, p = 0.047; θ = 90°, p = 0.037; cluster C3 (θ = 0°, p = 0.18; θ = 45°, p = 0.1; θ = 90°, p = 0.052), and cluster C4 (θ = 0°, p = 0.016; θ = 45°, p = 0.033; θ = 90°, p = 0.014) suggesting that the cluster C1 had tumors with more distinct edges or heterogeneous appearance compared with other clusters. CONCLUSIONS: Although this preliminary study showed promising associations between quantitative features and genetic mutations, it did not show any correlation between qualitative features and genetic mutations. Further studies with larger sample size are warranted to validate our preliminary data.

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Qualitative study whose research subjects were the members of a Health Family Strategy. and has as purpose to know their perspectives about health education and presents them through the dialogical conception of Paulo Freire. In the circles of culture, four themes emerged: family health team, health education, health education practice in team work and how to improve the stock of existing health education, were encode, decode and critically unveiled its concepts, challenges, opportunities and expectations of their educational practices. The field research was the development of a Primary Care Unit of Health of Cachoeira do Campo, Minas Gerais. The results showed that health education is recognized by the subjects as a liability, but its practice is facing cultural barriers, and receives little emphasis in the daily work.

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Estudo qualitativo cujos sujeitos de pesquisa foram os membros de uma equipe da estratégia de saúde da família, e teve como objetivo conhecer suas perspectivas sobre a educação em saúde e problematizá-las por meio da concepção dialógica de Paulo Freire. Nos círculos de cultura, os quatro temas geradores: equipe de saúde da família; educação em saúde; prática da educação em saúde no trabalho da equipe e de que maneira melhorar as ações de educação em saúde existentes, foram codificados, descodificados e desvelados criticamente seus conceitos, dificuldades, possibilidades e expectativas em relação a práticas educativas desenvolvidas. O campo de desenvolvimento da pesquisa foi uma Unidade de Atenção Básica em Saúde de Cachoeira do Campo, Minas Gerais. Os resultados demonstraram que a educação em saúde é reconhecida pelos sujeitos como uma responsabilidade, contudo sua prática se depara com entraves culturais e ainda recebe pouco destaque no cotidiano de trabalho.

Qualitative study whose research subjects were the members of a Health Family Strategy. and has as purpose to know their perspectives about health education and presents them through the dialogical conception of Paulo Freire. In the circles of culture, four themes emerged: family health team, health education, health education practice in team work and how to improve the stock of existing health education, were encode, decode and critically unveiled its concepts, challenges, opportunities and expectations of their educational practices. The field research was the development of a Primary Care Unit of Health of Cachoeira do Campo, Minas Gerais. The results showed that health education is recognized by the subjects as a liability, but its practice is facing cultural barriers, and receives little emphasis in the daily work.

Estudio cualitativo, cuyos sujetos de investigación fueron los miembros de un equipo de un programa de salud familiar, tuvo como objetivo: conocer las perspectivas del equipo sobre la educación en salud y problematizarlas a través de la concepción dialógica de Paulo Freire. En los círculos de cultura los cuatro temas generadores: equipo de salud de la família; educación em salud; practica de la educacion de la família en su trabajo diário y las maneras de mejorar la practica de la educación em la salud, fueron codificados, descodificados y develados criticamente sus conceptos, dificultades, posibilidades y expectativas en relación a sus prácticas educativas. El lugar donde se desarrolló la investigación fue una Unidad de Atención Básica en Salud de Cachoeira do Campo, Minas Gerais. Los resultados demuestraran que la educación en salud es reconocida por los sujetos como siendo una responsabilidad, sin embargo, su práctica se ve afectada por barreras culturales y poco reconocimiento en el trabajo diario.

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