Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 79
Filtrar
1.
Proc Natl Acad Sci U S A ; 121(11): e2309576121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38437559

RESUMO

An abundance of laboratory-based experiments has described a vigilance decrement of reducing accuracy to detect targets with time on task, but there are few real-world studies, none of which have previously controlled the environment to control for bias. We describe accuracy in clinical practice for 360 experts who examined >1 million women's mammograms for signs of cancer, whilst controlling for potential biases. The vigilance decrement pattern was not observed. Instead, test accuracy improved over time, through a reduction in false alarms and an increase in speed, with no significant change in sensitivity. The multiple-decision model explains why experts miss targets in low prevalence settings through a change in decision threshold and search quit threshold and propose it should be adapted to explain these observed patterns of accuracy with time on task. What is typically thought of as standard and robust research findings in controlled laboratory settings may not directly apply to real-world environments and instead large, controlled studies in relevant environments are needed.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/diagnóstico por imagem , Mamografia , Fadiga , Laboratórios , Projetos de Pesquisa
2.
Chemistry ; 29(19): e202203742, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36550089

RESUMO

Discrete spin crossover (SCO) heteronuclear cages are a rare class of materials which have potential use in next-generation molecular transport and catalysis. Previous investigations of cubic cage [Fe8 Pd6 L8 ]28+ constructed using semi-rigid metalloligands, found that FeII centers of the cage did not undergo spin transition. In this work, substitution of the secondary metal center at the face of the cage resulted in SCO behavior, evidenced by magnetic susceptibility, Mössbauer spectroscopy and single crystal X-ray diffraction. Structural comparisons of these two cages shed light on the possible interplay of inter- and intramolecular interactions associated with SCO in the NiII analogue, 1 ([Fe8 Ni6 L8 (CH3 CN)12 ]28+ ). The distorted octahedral coordination environment, as well as the occupation of the CH3 CN in the NiII axial positions of 1, prevented close packing of cages observed in the PdII analogue. This led to offset, distant packing arrangements whereby important areas within the cage underwent dramatic structural changes with the exhibition of SCO.

3.
Molecules ; 28(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36771074

RESUMO

We present five new dinuclear triple helicate compounds of types [Mn2L3](ClO4)4, [Co2L3](BF4)4, [Ni2L3](BF4)4, [Cu2L3](BF4)4, and [Zn2L3](BF4)4, where L is a previously reported semi-rigid ligand incorporating two α-diimine primary donor groups and two secondary 4-pyridyl donor groups. All complexes have been characterized in both solution and the solid state. Single crystal X-ray diffraction studies were used to probe the variation in the respective helical structures as the coordinated metal ion was altered, including the effect on the orientations of the secondary binding domains. The influence of the metal ion size, the spin state in the case of Fe(II), and the presence of Jahn-Teller distortions on the overall helical structure has been investigated. These results form a basis for the design and construction of new large metallosupramolecular architectures which manifest properties associated with the constituent helical metalloligand units.

4.
Br J Cancer ; 127(12): 2125-2132, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36224403

RESUMO

BACKGROUND: The diagnosis, management and prognosis of microinvasive breast carcinoma remain controversial. METHODS: We analysed the outcomes of patients with DCIS with and without microinvasion diagnosed between 2003 and 2012 within the Sloane project. RESULTS: Microinvasion was recorded in 521 of 11,285 patients (4.6%), with considerable variation in reported incidence among screening units (0-25%). Microinvasion was associated with high-grade DCIS, larger DCIS size, comedo necrosis and solid, cribriform architecture (all P < 0.001). Microinvasion was more frequent in patients who underwent mastectomy compared with breast-conserving surgery (BCS) (6.9% vs 3.6%, P < 0.001), and in those undergoing axillary nodal surgery (60.4% vs 30.3%, P < 0.001) including the subset undergoing BCS (43.4% vs 8.5%, P < 0.001). Nodal metastasis rate was low and not statistically significant difference from the DCIS only group (P = 0.68). Following median follow-up of 110 months, 3% of patients had recurrent ipsilateral high-grade DCIS, and 4.2% developed invasive carcinoma. The subsequent ipsilateral invasion was of Grade 3 in 71.4% of patients with microinvasion vs 30.4% in DCIS without microinvasion (P = 0.02). Distant metastasis and breast cancer mortality were higher with microinvasion compared with DCIS only (1.2% vs 0.3%, P = 0.01 and 2.1% vs 0.8%; P = 0.005). CONCLUSIONS: The higher breast cancer mortality with microinvasion indicates a more aggressive disease.


Assuntos
Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Humanos , Feminino , Carcinoma Intraductal não Infiltrante/cirurgia , Neoplasias da Mama/cirurgia , Mastectomia , Reino Unido
5.
Radiology ; 303(1): 54-62, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34981975

RESUMO

Background Improving diagnosis of ductal carcinoma in situ (DCIS) before surgery is important in choosing optimal patient management strategies. However, patients may harbor occult invasive disease not detected until definitive surgery. Purpose To assess the performance and clinical utility of mammographic radiomic features in the prediction of occult invasive cancer among women diagnosed with DCIS on the basis of core biopsy findings. Materials and Methods In this Health Insurance Portability and Accountability Act-compliant retrospective study, digital magnification mammographic images were collected from women who underwent breast core-needle biopsy for calcifications that was performed at a single institution between September 2008 and April 2017 and yielded a diagnosis of DCIS. The database query was directed at asymptomatic women with calcifications without a mass, architectural distortion, asymmetric density, or palpable disease. Logistic regression with regularization was used. Differences across training and internal test set by upstaging rate, age, lesion size, and estrogen and progesterone receptor status were assessed by using the Kruskal-Wallis or χ2 test. Results The study consisted of 700 women with DCIS (age range, 40-89 years; mean age, 59 years ± 10 [standard deviation]), including 114 with lesions (16.3%) upstaged to invasive cancer at subsequent surgery. The sample was split randomly into 400 women for the training set and 300 for the testing set (mean ages: training set, 59 years ± 10; test set, 59 years ± 10; P = .85). A total of 109 radiomic and four clinical features were extracted. The best model on the test set by using all radiomic and clinical features helped predict upstaging with an area under the receiver operating characteristic curve of 0.71 (95% CI: 0.62, 0.79). For a fixed high sensitivity (90%), the model yielded a specificity of 22%, a negative predictive value of 92%, and an odds ratio of 2.4 (95% CI: 1.8, 3.2). High specificity (90%) corresponded to a sensitivity of 37%, positive predictive value of 41%, and odds ratio of 5.0 (95% CI: 2.8, 9.0). Conclusion Machine learning models that use radiomic features applied to mammographic calcifications may help predict upstaging of ductal carcinoma in situ, which can refine clinical decision making and treatment planning. © RSNA, 2022.


Assuntos
Neoplasias da Mama , Calcinose , Carcinoma in Situ , Carcinoma Ductal de Mama , Carcinoma Intraductal não Infiltrante , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/patologia , Feminino , Humanos , Masculino , Mamografia , Pessoa de Meia-Idade , Estudos Retrospectivos
6.
Eur Radiol ; 32(1): 602-612, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34117912

RESUMO

OBJECTIVES: In breast cancer screening, two readers separately examine each woman's mammograms for signs of cancer. We examined whether preventing the two readers from seeing each other's decisions (blinding) affects behaviour and outcomes. METHODS: This cohort study used data from the CO-OPS breast-screening trial (1,119,191 women from 43 screening centres in England) where all discrepant readings were arbitrated. Multilevel models were fitted using Markov chain Monte Carlo to measure whether reader 2 conformed to the decisions of reader 1 when they were not blinded, and the effect of blinding on overall rates of recall for further tests and cancer detection. Differences in positive predictive value (PPV) were assessed using Pearson's chi-squared test. RESULTS: When reader 1 recalls, the probability of reader 2 also recalling was higher when not blinded than when blinded, suggesting readers may be influenced by the other's decision. Overall, women were less likely to be recalled when reader 2 was blinded (OR 0.923; 95% credible interval 0.864, 0.986), with no clear pattern in cancer detection rate (OR 1.029; 95% credible interval 0.970, 1.089; Bayesian p value 0.832). PPV was 22.1% for blinded versus 20.6% for not blinded (p < 0.001). CONCLUSIONS: Our results suggest that when not blinded, reader 2 is influenced by reader 1's decisions to recall (alliterative bias) which would result in bypassing arbitration and negate some of the benefits of double-reading. We found a relationship between blinding the second reader and slightly higher PPV of breast cancer screening, although this analysis may be confounded by other centre characteristics. KEY POINTS: • In Europe, it is recommended that breast screening mammograms are analysed by two readers but there is little evidence on the effect of 'blinding' the readers so they cannot see each other's decisions. • We found evidence that when the second reader is not blinded, they are more likely to agree with a recall decision from the first reader and less likely to make an independent judgement (alliterative error). This may reduce overall accuracy through bypassing arbitration. • This observational study suggests an association between blinding the second reader and higher positive predictive value of screening, but this may be confounded by centre characteristics.


Assuntos
Neoplasias da Mama , Detecção Precoce de Câncer , Teorema de Bayes , Neoplasias da Mama/diagnóstico por imagem , Estudos de Coortes , Feminino , Humanos , Mamografia , Programas de Rastreamento , Variações Dependentes do Observador
7.
Eur Radiol ; 32(2): 806-814, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34331118

RESUMO

OBJECTIVES: This study was designed to compare the detection of subtle lesions (calcification clusters or masses) when using the combination of digital breast tomosynthesis (DBT) and synthetic mammography (SM) with digital mammography (DM) alone or combined with DBT. METHODS: A set of 166 cases without cancer was acquired on a DBT mammography system. Realistic subtle calcification clusters and masses in the DM images and DBT planes were digitally inserted into 104 of the acquired cases. Three study arms were created: DM alone, DM with DBT and SM with DBT. Five mammographic readers located the centre of any lesion within the images that should be recalled for further investigation and graded their suspiciousness. A JAFROC figure of merit (FoM) and lesion detection fraction (LDF) were calculated for each study arm. The visibility of the lesions in the DBT images was compared with SM and DM images. RESULTS: For calcification clusters, there were no significant differences (p > 0.075) in FoM or LDF. For masses, the FoM and LDF were significantly improved in the arms using DBT compared to DM alone (p < 0.001). On average, both calcification clusters and masses were more visible on DBT than on DM and SM images. CONCLUSIONS: This study demonstrated that masses were detected better with DBT than with DM alone and there was no significant difference (p = 0.075) in LDF between DM&DBT and SM&DBT for calcifications clusters. Our results support previous studies that it may be acceptable to not acquire digital mammography alongside tomosynthesis for subtle calcification clusters and ill-defined masses. KEY POINTS: • The detection of masses was significantly better using DBT than with digital mammography alone. • The detection of calcification clusters was not significantly different between digital mammography and synthetic 2D images combined with tomosynthesis. • Our results support previous studies that it may be acceptable to not acquire digital mammography alongside tomosynthesis for subtle calcification clusters and ill-defined masses for the imaging technology used.


Assuntos
Neoplasias da Mama , Calcinose , Neoplasias , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Feminino , Humanos , Mamografia
8.
Molecules ; 27(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36235129

RESUMO

Inspired by ethnopharmacological knowledge, we conducted a bioassay-guided fractionation of the leaves of Tristaniopsis laurina which led to the discovery of a new anti-inflammatory compound, tristaenone A (1). The structure was elucidated by detailed spectroscopic data analysis, and the absolute configuration was established using X-ray crystallography analysis. Tristaenone A (1) suppressed LPS and IFN-γ-induced NO, TNF-α and IL-6 production in RAW 264.7 cells with IC50 values of 37.58 ± 2.45 µM, 80.6 ± 5.82 µM and 125.65 ± 0.34 µM, respectively. It also inhibited NF-κB nuclear translocation by 52.93 ± 14.14% at a concentration of 31.85 µM.


Assuntos
Lipopolissacarídeos , NF-kappa B , Animais , Anti-Inflamatórios/farmacologia , Austrália , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Fator de Necrose Tumoral alfa/metabolismo
9.
Br J Cancer ; 125(6): 884-892, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34168297

RESUMO

BACKGROUND: This study investigates whether quantitative breast density (BD) serves as an imaging biomarker for more intensive breast cancer screening by predicting interval, and node-positive cancers. METHODS: This case-control study of 1204 women aged 47-73 includes 599 cancer cases (302 screen-detected, 297 interval; 239 node-positive, 360 node-negative) and 605 controls. Automated BD software calculated fibroglandular volume (FGV), volumetric breast density (VBD) and density grade (DG). A radiologist assessed BD using a visual analogue scale (VAS) from 0 to 100. Logistic regression and area under the receiver operating characteristic curves (AUC) determined whether BD could predict mode of detection (screen-detected or interval); node-negative cancers; node-positive cancers, and all cancers vs. controls. RESULTS: FGV, VBD, VAS, and DG all discriminated interval cancers (all p < 0.01) from controls. Only FGV-quartile discriminated screen-detected cancers (p < 0.01). Based on AUC, FGV discriminated all cancer types better than VBD or VAS. FGV showed a significantly greater discrimination of interval cancers, AUC = 0.65, than of screen-detected cancers, AUC = 0.61 (p < 0.01) as did VBD (0.63 and 0.53, respectively, p < 0.001). CONCLUSION: FGV, VBD, VAS and DG discriminate interval cancers from controls, reflecting some masking risk. Only FGV discriminates screen-detected cancers perhaps adding a unique component of breast cancer risk.


Assuntos
Densidade da Mama , Neoplasias da Mama/diagnóstico por imagem , Mamografia/métodos , Idoso , Estudos de Casos e Controles , Detecção Precoce de Câncer , Feminino , Humanos , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Escala Visual Analógica
10.
Br J Cancer ; 124(5): 1009-1017, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33199800

RESUMO

BACKGROUND: The Sloane audit compares screen-detected ductal carcinoma in situ (DCIS) pathology with subsequent management and outcomes. METHODS: This was a national, prospective cohort study of DCIS diagnosed during 2003-2012. RESULTS: Among 11,337 patients, 7204 (64%) had high-grade DCIS. Over time, the proportion of high-grade disease increased (from 60 to 65%), low-grade DCIS decreased (from 10 to 6%) and mean size increased (from 21.4 to 24.1 mm). Mastectomy was more common for high-grade (36%) than for low-grade DCIS (15%). Few (6%) patients treated with breast-conserving surgery (BCS) had a surgical margin <1 mm. Of the 9191 women diagnosed in England (median follow-up 9.4 years), 7% developed DCIS or invasive malignancy in the ipsilateral and 5% in the contralateral breast. The commonest ipsilateral event was invasive carcinoma (n = 413), median time 62 months, followed by DCIS (n = 225), at median 37 months. Radiotherapy (RT) was most protective against recurrence for high-grade DCIS (3.2% for high-grade DCIS with RT compared to 6.9% without, compared with 2.3 and 3.0%, respectively, for low/intermediate-grade DCIS). Ipsilateral DCIS events lessened after 5 years, while the risk of ipsilateral invasive cancer remained consistent to beyond 10 years. CONCLUSION: DCIS pathology informs patient management and highlights the need for prolonged follow-up of screen-detected DCIS.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/epidemiologia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Intraductal não Infiltrante/epidemiologia , Carcinoma Intraductal não Infiltrante/cirurgia , Feminino , Seguimentos , Humanos , Mastectomia , Prognóstico , Estudos Prospectivos , Reino Unido/epidemiologia
11.
Eur Radiol ; 31(7): 5335-5343, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33475774

RESUMO

OBJECTIVES: To study how radiologists' perceived ability to interpret digital mammography (DM) images is affected by decreases in image quality. METHODS: One view from 45 DM cases (including 30 cancers) was degraded to six levels each of two acquisition-related issues (lower spatial resolution and increased quantum noise) and three post-processing-related issues (lower and higher contrast and increased correlated noise) seen during clinical evaluation of DM systems. The images were shown to fifteen breast screening radiologists from five countries. Aware of lesion location, the radiologists selected the most-degraded mammogram (indexed from 1 (reference) to 7 (most degraded)) they still felt was acceptable for interpretation. The median selected index, per degradation type, was calculated separately for calcification and soft tissue (including normal) cases. Using the two-sided, non-parametric Mann-Whitney test, the median indices for each case and degradation type were compared. RESULTS: Radiologists were not tolerant to increases (medians: 1.5 (calcifications) and 2 (soft tissue)) or decreases (median: 2, for both types) in contrast, but were more tolerant to correlated noise (median: 3, for both types). Increases in quantum noise were tolerated more for calcifications than for soft tissue cases (medians: 3 vs. 4, p = 0.02). Spatial resolution losses were considered less acceptable for calcification detection than for soft tissue cases (medians: 3.5 vs. 5, p = 0.001). CONCLUSIONS: Perceived ability of radiologists for image interpretation in DM was affected not only by image acquisition-related issues but also by image post-processing issues, and some of those issues affected calcification cases more than soft tissue cases. KEY POINTS: • Lower spatial resolution and increased quantum noise affected the radiologists' perceived ability to interpret calcification cases more than soft tissue lesion or normal cases. • Post-acquisition image processing-related effects, not only image acquisition-related effects, also impact the perceived ability of radiologists to interpret images and detect lesions. • In addition to current practices, post-acquisition image processing-related effects need to also be considered during the testing and evaluation of digital mammography systems.


Assuntos
Neoplasias da Mama , Calcinose , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Feminino , Humanos , Mamografia , Intensificação de Imagem Radiográfica , Radiologistas
12.
Radiology ; 290(3): 629-637, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30526360

RESUMO

Purpose To report the impact of changing from screen-film mammography to digital mammography (DM) in a large organized national screening program. Materials and Methods A retrospective analysis of prospectively collected annual screening data from 2009-2010 to 2015-2016 for the 80 facilities of the English National Health Service Breast Cancer Screening Program, together with estimates of DM usage for three time periods, enabled the effect of DM to be measured in a study of 11.3 million screening episodes in women aged 45-70 years (mean age, 59 years). Regression models were used to estimate percentage and absolute change in detection rates due to DM. Results The overall cancer detection rate was 14% greater with DM (P < .001). There were higher rates of detection of grade 1 and 2 invasive cancers (both ductal and lobular), but no change in the detection of grade 3 invasive cancers. The recall rate was almost unchanged by the introduction of DM. At prevalent (first) screening episodes for women aged 45-52 years, DM increased the overall detection rate by 19% (P < .001) and for incident screening episodes in women aged 53-70 years by 13% (P < .001). Conclusion The overall cancer detection rate was 14% greater with digital mammography with no change in recall rates and without confounding by changes in other factors. There was a substantially higher detection of grade 1 and grade 2 invasive cancers, including both ductal and lobular cancers, but no change in the detection of grade 3 invasive cancers. © RSNA, 2018 Online supplemental material is available for this article. See also the editorial by C.I. Lee and J.M. Lee in this issue.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Continuidade da Assistência ao Paciente/estatística & dados numéricos , Mamografia/métodos , Idoso , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Detecção Precoce de Câncer , Inglaterra/epidemiologia , Feminino , Humanos , Programas de Rastreamento , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Estudos Retrospectivos , Medicina Estatal
13.
Eur Radiol ; 29(9): 4825-4832, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30993432

RESUMO

PURPOSE: To study the feasibility of automatically identifying normal digital mammography (DM) exams with artificial intelligence (AI) to reduce the breast cancer screening reading workload. METHODS AND MATERIALS: A total of 2652 DM exams (653 cancer) and interpretations by 101 radiologists were gathered from nine previously performed multi-reader multi-case receiver operating characteristic (MRMC ROC) studies. An AI system was used to obtain a score between 1 and 10 for each exam, representing the likelihood of cancer present. Using all AI scores between 1 and 9 as possible thresholds, the exams were divided into groups of low- and high likelihood of cancer present. It was assumed that, under the pre-selection scenario, only the high-likelihood group would be read by radiologists, while all low-likelihood exams would be reported as normal. The area under the reader-averaged ROC curve (AUC) was calculated for the original evaluations and for the pre-selection scenarios and compared using a non-inferiority hypothesis. RESULTS: Setting the low/high-likelihood threshold at an AI score of 5 (high likelihood > 5) results in a trade-off of approximately halving (- 47%) the workload to be read by radiologists while excluding 7% of true-positive exams. Using an AI score of 2 as threshold yields a workload reduction of 17% while only excluding 1% of true-positive exams. Pre-selection did not change the average AUC of radiologists (inferior 95% CI > - 0.05) for any threshold except at the extreme AI score of 9. CONCLUSION: It is possible to automatically pre-select exams using AI to significantly reduce the breast cancer screening reading workload. KEY POINTS: • There is potential to use artificial intelligence to automatically reduce the breast cancer screening reading workload by excluding exams with a low likelihood of cancer. • The exclusion of exams with the lowest likelihood of cancer in screening might not change radiologists' breast cancer detection performance. • When excluding exams with the lowest likelihood of cancer, the decrease in true-positive recalls would be balanced by a simultaneous reduction in false-positive recalls.


Assuntos
Inteligência Artificial , Neoplasias da Mama/diagnóstico por imagem , Detecção Precoce de Câncer/métodos , Mamografia/métodos , Reações Falso-Negativas , Reações Falso-Positivas , Estudos de Viabilidade , Feminino , Humanos , Programas de Rastreamento/métodos , Probabilidade , Curva ROC , Radiologistas , Carga de Trabalho
14.
Ultraschall Med ; 40(6): 757-763, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29879743

RESUMO

PURPOSE: Optoacoustic imaging with ultrasound (OPUS) can assess in-vivo perfusion/oxygenation through surrogate measures of oxy, deoxy and total hemoglobin content in tissues. The primary aim of our study was to evaluate the ability of OPUS to detect physiological changes in the breast during the menstrual cycle and to determine qualitative/quantitative metrics of normal parenchymal tissue in pre-/post-menopausal women. The secondary aim was to assess the technique's repeatability. MATERIALS AND METHODS: We performed a prospective ethically approved study in volunteers using OPUS (700, 800 and 850 nm wavelengths) in the proliferative/follicular and secretory phase of the menstrual cycle. Regions of interest (ROIs) were drawn on the most superficial region of fibroglandular tissue and same-day intra-observer repeatability was assessed. We used t-tests to interrogate differences in the OPUS measurements due to hormonal changes and interclass correlation coefficients/Bland-Altman plots to evaluate the repeatability of mean ROI signal intensities. RESULTS: 22 pre-menopausal and 8 post-menopausal volunteers were recruited. 21 participants underwent repeatability examinations. OPUS intensity values were significantly higher (p < 0.0001) at all excitation wavelengths in the secretory compared to the proliferative/follicular phase. Post-menopausal volunteers showed similar optoacoustic values to the proliferative/follicular phase of pre-menopausal volunteers. The repeatability of the technique was comparable to other handheld ultrasound modalities. CONCLUSION: OPUS detects changes in perfusion/vascularity related to the menstrual cycle and menopausal status of breast parenchyma.


Assuntos
Neoplasias da Mama , Hormônios , Mama , Neoplasias da Mama/diagnóstico por imagem , Feminino , Hormônios/fisiologia , Humanos , Ciclo Menstrual , Óptica e Fotônica , Estudos Prospectivos
15.
Radiology ; 287(3): 749-757, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29634439

RESUMO

Purpose To investigate the effect of double readings by a second radiologist on recall rates, cancer detection, and characteristics of cancers detected in the National Health Service Breast Screening Program in England. Materials and Methods In this retrospective analysis, 805 206 women were evaluated through screening and diagnostic test results by extracting 1 year of routine data from 33 English breast screening centers. Centers used double reading of digital mammograms, with arbitration if there were discrepant interpretations. Information on reader decisions, with results of follow-up tests, were used to explore the effect of the second reader. The statistical tests used were the test for equality of proportions, the χ2 test for independence, and the t test. Results The first reader recalled 4.76% of women (38 295 of 805 206 women; 95% confidence interval [CI]: 4.71%, 4.80%). Two readers recalled 6.19% of women in total (49 857 of 805 206 women; 95% CI: 6.14%, 6.24%), but arbitration of discordant readings reduced the recall rate to 4.08% (32 863 of 805 206 women; 95% CI: 4.04%, 4.12%; P < .001). A total of 7055 cancers were detected, of which 627 (8.89%; 95% CI: 8.22%, 9.55%; P < .001) were detected by the second reader only. These additional cancers were more likely to be ductal carcinoma in situ (30.5% [183 of 600] vs 22.0% [1344 of 6114]; P < .001), and additional invasive cancers were smaller (mean size, 14.2 vs 16.7 mm; P < .001), had fewer involved nodes, and were likely to be lower grade. Conclusion Double reading with arbitration reduces recall and increases cancer detection compared with single reading. Cancers detected only by the second reader were smaller, of lower grade, and had less nodal involvement. © RSNA, 2018.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Programas de Rastreamento/métodos , Variações Dependentes do Observador , Encaminhamento e Consulta , Idoso , Mama/diagnóstico por imagem , Estudos de Coortes , Inglaterra , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos
16.
N Engl J Med ; 368(13): 1199-209, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23484797

RESUMO

BACKGROUND: The management of metastatic breast cancer requires monitoring of the tumor burden to determine the response to treatment, and improved biomarkers are needed. Biomarkers such as cancer antigen 15-3 (CA 15-3) and circulating tumor cells have been widely studied. However, circulating cell-free DNA carrying tumor-specific alterations (circulating tumor DNA) has not been extensively investigated or compared with other circulating biomarkers in breast cancer. METHODS: We compared the radiographic imaging of tumors with the assay of circulating tumor DNA, CA 15-3, and circulating tumor cells in 30 women with metastatic breast cancer who were receiving systemic therapy. We used targeted or whole-genome sequencing to identify somatic genomic alterations and designed personalized assays to quantify circulating tumor DNA in serially collected plasma specimens. CA 15-3 levels and numbers of circulating tumor cells were measured at identical time points. RESULTS: Circulating tumor DNA was successfully detected in 29 of the 30 women (97%) in whom somatic genomic alterations were identified; CA 15-3 and circulating tumor cells were detected in 21 of 27 women (78%) and 26 of 30 women (87%), respectively. Circulating tumor DNA levels showed a greater dynamic range, and greater correlation with changes in tumor burden, than did CA 15-3 or circulating tumor cells. Among the measures tested, circulating tumor DNA provided the earliest measure of treatment response in 10 of 19 women (53%). CONCLUSIONS: This proof-of-concept analysis showed that circulating tumor DNA is an informative, inherently specific, and highly sensitive biomarker of metastatic breast cancer. (Funded by Cancer Research UK and others.).


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/secundário , DNA de Neoplasias/sangue , Mucina-1/sangue , Metástase Neoplásica/diagnóstico , Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Feminino , Estudo de Associação Genômica Ampla , Humanos , Mutação , Metástase Neoplásica/diagnóstico por imagem , Metástase Neoplásica/genética , Prognóstico , Radiografia , Sensibilidade e Especificidade , Análise de Sequência de DNA/métodos , Carga Tumoral
17.
Eur Radiol ; 26(3): 874-83, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26105023

RESUMO

OBJECTIVE: To compare the performance of different types of detectors in breast cancer detection. METHODS: A mammography image set containing subtle malignant non-calcification lesions, biopsy-proven benign lesions, simulated malignant calcification clusters and normals was acquired using amorphous-selenium (a-Se) detectors. The images were adapted to simulate four types of detectors at the same radiation dose: digital radiography (DR) detectors with a-Se and caesium iodide (CsI) convertors, and computed radiography (CR) detectors with a powder phosphor (PIP) and a needle phosphor (NIP). Seven observers marked suspicious and benign lesions. Analysis was undertaken using jackknife alternative free-response receiver operating characteristics weighted figure of merit (FoM). The cancer detection fraction (CDF) was estimated for a representative image set from screening. RESULTS: No significant differences in the FoMs between the DR detectors were measured. For calcification clusters and non-calcification lesions, both CR detectors' FoMs were significantly lower than for DR detectors. The calcification cluster's FoM for CR NIP was significantly better than for CR PIP. The estimated CDFs with CR PIP and CR NIP detectors were up to 15% and 22% lower, respectively, than for DR detectors. CONCLUSION: Cancer detection is affected by detector type, and the use of CR in mammography should be reconsidered. KEY POINTS: The type of mammography detector can affect the cancer detection rates. CR detectors performed worse than DR detectors in mammography. Needle phosphor CR performed better than powder phosphor CR. Calcification clusters detection is more sensitive to detector type than other cancers.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Mamografia/instrumentação , Idoso , Detecção Precoce de Câncer/instrumentação , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Mamografia/métodos , Programas de Rastreamento/instrumentação , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Agulhas , Variações Dependentes do Observador , Curva ROC , Intensificação de Imagem Radiográfica/métodos
18.
JAMA ; 315(18): 1956-65, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-27163985

RESUMO

IMPORTANCE: Interpreting screening mammograms is a difficult repetitive task that can result in missed cancers and false-positive recalls. In the United Kingdom, 2 film readers independently evaluate each mammogram to search for signs of cancer and examine digital mammograms in batches. However, a vigilance decrement (reduced detection rate with time on task) has been observed in similar settings. OBJECTIVE: To determine the effect of changing the order for the second film reader of batches of screening mammograms on rates of breast cancer detection. DESIGN, SETTING, AND PARTICIPANTS: A multicenter, double-blind, cluster randomized clinical trial conducted at 46 specialized breast screening centers from the National Health Service Breast Screening Program in England for 1 year (all between December 20, 2012, and November 3, 2014). Three hundred sixty readers participated (mean, 7.8 readers per center)-186 radiologists, 143 radiography advanced practitioners, and 31 breast clinicians, all fully qualified to report mammograms in the NHS breast screening program. INTERVENTIONS: The 2 readers examined each batch of digital mammograms in the same order in the control group and in the opposite order to one another in the intervention group. MAIN OUTCOMES AND MEASURES: The primary outcome was cancer detection rate; secondary outcomes were rates of recall and disagreements between readers. RESULTS: Among 1,194,147 women (mean age, 59.3; SD, 7.49) who had screening mammograms (596,642 in the intervention group; 597,505 in the control group), the images were interpreted in 37,688 batches (median batch size, 35; interquartile range [IQR]; 16-46), with each reader interpreting a median of 176 batches (IQR, 96-278). After completion of all subsequent diagnostic tests, a total of 10,484 cases (0.88%) of breast cancer were detected. There was no significant difference in cancer detection rate with 5272 cancers (0.88%) detected in the intervention group vs 5212 cancers (0.87%) detected in the control group (difference, 0.01% points; 95% CI, -0.02% to 0.04% points; recall rate, 24,681 [4.14%] vs 24,894 [4.17%]; difference, -0.03% points; 95% CI, -0.10% to 0.04% points; or rate of reader disagreements, 20,471 [3.43%] vs 20,793 [3.48%]; difference, -0.05% points; 95% CI, -0.11% to 0.02% points). CONCLUSIONS AND RELEVANCE: Interpretation of batches of mammograms by qualified screening mammography readers using a different order vs the same order for the second reading resulted in no significant difference in rates of detection of breast cancer. TRIAL REGISTRATION: isrctn.org Identifier: ISRCTN46603370.


Assuntos
Atenção , Neoplasias da Mama/diagnóstico por imagem , Mamografia , Radiologia , Método Duplo-Cego , Inglaterra , Feminino , Humanos , Modelos Logísticos , Mamografia/estatística & dados numéricos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Radiologia/estatística & dados numéricos , Tamanho da Amostra
19.
Radiology ; 272(1): 73-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24666474

RESUMO

PURPOSE: To retrospectively review diagnostic mammography in women diagnosed with breast cancer who previously had mantle field radiation therapy for Hodgkin disease in England and Wales over a period of 30 years. MATERIALS AND METHODS: From a national cohort study of 5002 women treated with supradiaphragmatic radiation therapy when they were younger than 36 years (mean, 22.1 years) during 1956-2003, 392 patients developed breast cancer. With ethics committee approval and informed consent, mammograms were obtained that showed 230 tumors in 222 (56.6%) patients from 95 hospitals, and the size and appearance of each carcinoma was recorded by two breast radiologists. Comparison was made with a historical report of more than 1000 general-population breast cancers by using Pearson χ(2) test. RESULTS: Thirty-eight tumors were occult on mammograms. Mean tumor maximum diameter was 12.3 mm (n = 81) on oblique view. The quadrant distribution of the tumors was significantly different (P < .001) from the historic controls, and chest radiation therapy patients had a greater proportion of tumors in the upper outer (66.9% [107 of 160] vs 48.7% [385 of 784]) and, to a lesser extent, lower inner (10.6% [17 of 160] vs 7.8% [61 of 784]) quadrants. The dominant radiologic feature was of an irregular mass (56.8% [109 of 192]) followed by microcalcifications (25.0% [48 of 192]). CONCLUSION: This study suggests that in patients who previously underwent mantle radiation therapy for Hodgkin disease, breast cancers are more commonly seen within the upper outer quadrants than are cancers in the general population. Poorly defined masses were the most common appearance.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Doença de Hodgkin/radioterapia , Neoplasias Induzidas por Radiação/diagnóstico por imagem , Neoplasias Induzidas por Radiação/epidemiologia , Adulto , Inglaterra/epidemiologia , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , País de Gales/epidemiologia
20.
AJR Am J Roentgenol ; 203(2): 387-93, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25055275

RESUMO

OBJECTIVE. The objective of our study was to investigate the effect of image processing on the detection of cancers in digital mammography images. MATERIALS AND METHODS. Two hundred seventy pairs of breast images (both breasts, one view) were collected from eight systems using Hologic amorphous selenium detectors: 80 image pairs showed breasts containing subtle malignant masses; 30 image pairs, biopsy-proven benign lesions; 80 image pairs, simulated calcification clusters; and 80 image pairs, no cancer (normal). The 270 image pairs were processed with three types of image processing: standard (full enhancement), low contrast (intermediate enhancement), and pseudo-film-screen (no enhancement). Seven experienced observers inspected the images, locating and rating regions they suspected to be cancer for likelihood of malignancy. The results were analyzed using a jackknife-alternative free-response receiver operating characteristic (JAFROC) analysis. RESULTS. The detection of calcification clusters was significantly affected by the type of image processing: The JAFROC figure of merit (FOM) decreased from 0.65 with standard image processing to 0.63 with low-contrast image processing (p = 0.04) and from 0.65 with standard image processing to 0.61 with film-screen image processing (p = 0.0005). The detection of noncalcification cancers was not significantly different among the image-processing types investigated (p > 0.40). CONCLUSION. These results suggest that image processing has a significant impact on the detection of calcification clusters in digital mammography. For the three image-processing versions and the system investigated, standard image processing was optimal for the detection of calcification clusters. The effect on cancer detection should be considered when selecting the type of image processing in the future.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Mamografia/métodos , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Idoso , Biópsia , Feminino , Humanos , Pessoa de Meia-Idade , Reino Unido
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA