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1.
Breast Care (Basel) ; 16(5): 435-443, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34720802

RESUMO

INTRODUCTION: Due to the increasing use of dynamic breast MRI and the limited availability of MR-guided interventions, MRI-detected lesions usually undergo a second-look ultrasound (SLUS). We investigated the safety of a negative SLUS and a benign SLUS correlate in excluding malignant and high-risk lesions (B3) and evaluated criteria for the rate of detection on SLUS. METHODS: In the retrospective analysis, all breast MRIs performed between 2011 and 2013 were screened for newly detected lesions. We analyzed the SLUS detection rate dependent on breast density, mass character, lesion size, and histology. We calculated the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of a negative and benign SLUS for malignant lesions (B5) and lesions requiring surgical excision (including high-risk and B5 lesions). RESULTS: We successfully correlated 110 of 397 lesions. The detection rate was significantly higher for mass than for non-mass lesions and correlated with lesion size for mass lesions only. Lesions without/with a benign SLUS correlate were more frequently benign (including B3) or required no further procedure (B2). The sensitivity of SLUS in the detection of B3 and B5 lesions was 58%, and 73% in the detection of B5 lesions. The NPV of a negative or benign SLUS for B3 and B5 lesions was 89%, and 96% for B5 lesions. DISCUSSION: SLUS is a safe diagnostic tool for the management of MRI-detected lesions and can spare patients from undergoing invasive procedures.

2.
PLoS One ; 14(1): e0210291, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30625220

RESUMO

BACKGROUND: The extent of intraductal carcinoma in situ (DCIS) is commonly underestimated due to the discontinuous growth and lack of microcalcifications. Specimen radiography has been established to reduce the rate of re-excision. However, the predictive value for margin assessment with conventional specimen radiography for DCIS is low. In this study we assessed the potential of grating-based phase-contrast computed tomography (GBPC-CT) at conventional X-ray sources for specimen tomography of DCIS containing samples. MATERIALS AND METHODS: GBPC-CT was performed on four ex-vivo breast specimens containing DCIS and invasive carcinoma of non-specific type. Phase-contrast and absorption-based datasets were manually matched with corresponding histological slices as the standard of reference. RESULTS: Matching of CT images and histology was successful. GBPC-CT showed an improved soft tissue contrast compared to absorption-based images revealing more histological details in the same sections. Non-calcifying DCIS exceeding the invasive tumor could be correlated to areas of dilated bright ducts around the tumor. CONCLUSIONS: GBPC-CT imaging at conventional X-ray sources offers improved depiction quality for the imaging of breast tissue samples compared to absorption-based imaging, allows the identification of diagnostically relevant tissue details, and provides full three-dimensional assessment of sample margins.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Calcinose/diagnóstico por imagem , Calcinose/patologia , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/cirurgia , Feminino , Humanos , Técnicas In Vitro , Mamografia/métodos , Microscopia de Contraste de Fase/métodos , Estudos Prospectivos
3.
Eur J Radiol ; 89: 27-32, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28267545

RESUMO

X-Ray Phase-Contrast (XPC) imaging is a novel technology with a great potential for applications in clinical practice, with breast imaging being of special interest. This work introduces an intuitive methodology to combine and visualize relevant diagnostic features, present in the X-ray attenuation, phase shift and scattering information retrieved in XPC imaging, using a Fourier domain fusion algorithm. The method allows to present complementary information from the three acquired signals in one single image, minimizing the noise component and maintaining visual similarity to a conventional X-ray image, but with noticeable enhancement in diagnostic features, details and resolution. Radiologists experienced in mammography applied the image fusion method to XPC measurements of mastectomy samples and evaluated the feature content of each input and the fused image. This assessment validated that the combination of all the relevant diagnostic features, contained in the XPC images, was present in the fused image as well.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Análise de Fourier , Processamento de Imagem Assistida por Computador/métodos , Mamografia/métodos , Adulto , Algoritmos , Feminino , Humanos , Reprodutibilidade dos Testes , Raios X
4.
Psychooncology ; 26(1): 74-80, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26898732

RESUMO

OBJECTIVE: There is ongoing debate whether cancer qualifies as traumatic stressor. We investigated prevalence and course of posttraumatic stress in patients with early breast cancer (BC) during their first year after diagnosis and determined effects of mastectomy and chemotherapy. METHODS: Patients with stage 0-III BC aged ≤65 years were evaluated with the Structured Clinical Interview for DSM-IV modules for acute and posttraumatic stress disorder (ASD and PTSD, respectively) before treatment, after chemotherapy, and 1 year after diagnosis. Matched controls were assessed at matched intervals. Effects of time, mastectomy, and chemotherapy on BC-related PTSD symptom severity were tested with linear mixed model analysis. RESULTS: Stress disorder (ASD or PTSD) related to BC was diagnosed in 6 (3.6%) of 166 patients before treatment and in 3 patients (2.0%) 1 year later. The rate of patients who experienced PTSD symptoms related to BC decreased from 82.5 to 57.3% (p < 0.001), and the mean of BC-related PTSD symptoms diminished from 3.1 to 1.7 (p < 0.001). Only university education significantly predicted the course of BC-related PTSD symptom severity (p = 0.009). In 60 controls, no diagnosis of stress disorder, a rate of 18% women experiencing PTSD symptoms, and a mean of 0.4 PTSD symptoms (p vs. patients <0.001) were found. CONCLUSIONS: Most newly diagnosed patients with BC experience PTSD symptoms, whereas full diagnoses of DSM-IV stress disorder are rare. Symptoms diminish somewhat within 1 year furthered by university education but independently from mastectomy and chemotherapy. Throughout the year after diagnosis, having BC entails markedly increased PTSD symptom burden. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Neoplasias da Mama/psicologia , Índice de Gravidade de Doença , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/psicologia , Idoso , Neoplasias da Mama/diagnóstico , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Prevalência , Prognóstico , Estudos Prospectivos
5.
Sci Rep ; 6: 36991, 2016 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-27841341

RESUMO

Breast microcalcifications play an essential role in the detection and evaluation of early breast cancer in clinical diagnostics. However, in digital mammography, microcalcifications are merely graded with respect to their global appearance within the mammogram, while their interior microstructure remains spatially unresolved and therefore not considered in cancer risk stratification. In this article, we exploit the sub-pixel resolution sensitivity of X-ray dark-field contrast for clinical microcalcification assessment. We demonstrate that the micromorphology, rather than chemical composition of microcalcification clusters (as hypothesised by recent literature), determines their absorption and small-angle scattering characteristics. We show that a quantitative classification of the inherent microstructure as ultra-fine, fine, pleomorphic and coarse textured is possible. Insights underlying the micromorphological nature of breast calcifications are verified by comprehensive high-resolution micro-CT measurements. We test the determined microtexture of microcalcifications as an indicator for malignancy and demonstrate its potential to improve breast cancer diagnosis, by providing a non-invasive tool for sub-resolution microcalcification assessment. Our results indicate that dark-field imaging of microcalcifications may enhance the diagnostic validity of current microcalcification analysis and reduce the number of invasive procedures.


Assuntos
Neoplasias da Mama/diagnóstico , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Feminino , Humanos , Mamografia , Microtomografia por Raio-X
6.
Phys Med Biol ; 61(24): 8750-8761, 2016 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-27893445

RESUMO

Since the breast is one of the most radiosensitive organs, mammography is arguably the area where lowering radiation dose is of the uttermost importance. Phase-based x-ray imaging methods can provide opportunities in this sense, since they do not require x-rays to be stopped in tissue for image contrast to be generated. Therefore, x-ray energy can be considerably increased compared to those usually exploited by conventional mammography. In this article we show how a novel, optimized approach can lead to considerable dose reductions. This was achieved by matching the edge-illumination phase method, which reaches very high angular sensitivity also at high x-ray energies, to an appropriate image processing algorithm and to a virtually noise-free detection technology capable of reaching almost 100% efficiency at the same energies. Importantly, while proof-of-concept was obtained at a synchrotron, the method has potential for a translation to conventional sources.


Assuntos
Mamografia/métodos , Doses de Radiação , Algoritmos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Mamografia/instrumentação , Pessoa de Meia-Idade , Razão Sinal-Ruído , Síncrotrons , Raios X
7.
PLoS One ; 11(6): e0158306, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27362638

RESUMO

OBJECTIVES: Neoadjuvant chemotherapy is the state-of-the-art treatment in advanced breast cancer. A correct visualization of the post-therapeutic tumor size is of high prognostic relevance. X-ray phase-contrast computed tomography (PC-CT) has been shown to provide improved soft-tissue contrast at a resolution formerly restricted to histopathology, at low doses. This study aimed at assessing ex-vivo the potential use of PC-CT for visualizing the effects of neoadjuvant chemotherapy on breast carcinoma. MATERIALS AND METHODS: The analysis was performed on two ex-vivo formalin-fixed mastectomy samples containing an invasive carcinoma removed from two patients treated with neoadjuvant chemotherapy. Images were matched with corresponding histological slices. The visibility of typical post-therapeutic tissue changes was assessed and compared to results obtained with conventional clinical imaging modalities. RESULTS: PC-CT depicted the different tissue types with an excellent correlation to histopathology. Post-therapeutic tissue changes were correctly visualized and the residual tumor mass could be detected. PC-CT outperformed clinical imaging modalities in the detection of chemotherapy-induced tissue alterations including post-therapeutic tumor size. CONCLUSIONS: PC-CT might become a unique diagnostic tool in the prediction of tumor response to neoadjuvant chemotherapy. PC-CT might be used to assist during histopathological diagnosis, offering a high-resolution and high-contrast virtual histological tool for the accurate delineation of tumor boundaries.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Mama/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Antineoplásicos/uso terapêutico , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Terapia Neoadjuvante , Fixação de Tecidos , Resultado do Tratamento
8.
PLoS One ; 10(6): e0130776, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26110618

RESUMO

Phase-contrast mammography using laboratory X-ray sources is a promising approach to overcome the relatively low sensitivity and specificity of clinical, absorption-based screening. Current research is mostly centered on identifying potential diagnostic benefits arising from phase-contrast and dark-field mammography and benchmarking the latter with conventional state-of-the-art imaging methods. So far, little effort has been made to adjust this novel imaging technique to clinical needs. In this article, we address the key points for a successful implementation to a clinical routine in the near future and present the very first dose-compatible and rapid scan-time phase-contrast mammograms of both a freshly dissected, cancer-bearing mastectomy specimen and a mammographic accreditation phantom.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mamografia/métodos , Intensificação de Imagem Radiográfica/métodos , Humanos , Imagens de Fantasmas
9.
Eur Radiol ; 25(12): 3659-68, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25956934

RESUMO

OBJECTIVES: Conventional X-ray attenuation-based contrast is inherently low for the soft-tissue components of the female breast. To overcome this limitation, we investigate the diagnostic merits arising from dark-field mammography by means of certain tumour structures enclosed within freshly dissected mastectomy samples. METHODS: We performed grating-based absorption, absolute phase and dark-field mammography of three freshly dissected mastectomy samples containing bi- and multifocal carcinoma using a compact, laboratory Talbot-Lau interferometer. Preoperative in vivo imaging (digital mammography, ultrasound, MRI), postoperative histopathological analysis and ex vivo digital mammograms of all samples were acquired for the diagnostic verification of our results. RESULTS: In the diagnosis of multifocal tumour growth, dark-field mammography seems superior to standard breast imaging modalities, providing a better resolution of small, calcified tumour nodules, demarcation of tumour boundaries with desmoplastic stromal response and spiculated soft-tissue strands extending from an invasive ductal breast cancer. CONCLUSIONS: On the basis of selected cases, we demonstrate that dark-field mammography is capable of outperforming conventional mammographic imaging of tumour features in both calcified and non-calcified tumours. Presuming dose optimization, our results encourage further studies on larger patient cohorts to identify those patients that will benefit the most from this promising additional imaging modality. KEY POINTS: • X-ray dark-field mammography provides significantly improved visualization of tumour features • X-ray dark-field mammography is capable of outperforming conventional mammographic imaging • X-ray dark-field mammography provides imaging sensitivity towards highly dispersed calcium grains.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Mamografia/métodos , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mastectomia
10.
PLoS One ; 9(5): e93502, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24824594

RESUMO

Phase-contrast x-ray imaging is a promising improvement of conventional absorption-based mammography for early tumor detection. This potential has been demonstrated recently, utilizing structured gratings to obtain differential phase and dark-field scattering images. However, the inherently anisotropic imaging sensitivity of the proposed mono-directional approach yields only insufficient diagnostic information, and has low diagnostic sensitivity to highly oriented structures. To overcome these limitations, we present a two-directional x-ray phase-contrast mammography approach and demonstrate its advantages by applying it to a freshly dissected, cancerous mastectomy breast specimen. We illustrate that the two-directional scanning procedure overcomes the insufficient diagnostic value of a single scan, and reliably detects tumor structures, independently from their orientation within the breast. Our results indicate the indispensable diagnostic necessity and benefit of a multi-directional approach for x-ray phase-contrast mammography.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Mamografia/métodos , Diagnóstico por Imagem , Feminino , Humanos , Sensibilidade e Especificidade
11.
PLoS One ; 9(5): e97101, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24824169

RESUMO

BACKGROUND: Fibroadenoma is the most common benign solid breast lesion type and a very common cause for histologic assessment. To justify a conservative therapy, a highly specific discrimination between fibroadenomas and other breast lesions is crucial. Phase-contrast imaging offers improved soft-tissue contrast and differentiability of fine structures combined with the potential of 3-dimensional imaging. In this study we assessed the potential of grating-based phase-contrast CT imaging for visualizing diagnostically relevant features of fibroadenomas. MATERIALS AND METHODS: Grating-based phase-contrast CT was performed on six ex-vivo formalin-fixed breast specimens containing a fibroadenoma and three samples containing benign changes that resemble fibroadenomas using Talbot Lau interferometry and a polychromatic X-ray source. Phase-contrast and simultaneously acquired absorption-based 3D-datasets were manually matched with corresponding histological slices. The visibility of diagnostically valuable features was assessed in comparison with histology as the gold-standard. RESULTS: In all cases, matching of grating-based phase-contrast CT images and histology was successfully completed. Grating-based phase-contrast CT showed greatly improved differentiation of fine structures and provided accurate depiction of strands of fibrous tissue within the fibroadenomas as well as of the diagnostically valuable dilated, branched ductuli of the fibroadenomas. A clear demarcation of tumor boundaries in all cases was provided by phase- but not absorption-contrast CT. CONCLUSIONS: Pending successful translation of the technology to a clinical setting and considerable reduction of the required dose, the data presented here suggest that grating-based phase-contrast CT may be used as a supplementary non-invasive diagnostic tool in breast diagnostics. Phase-contrast CT may thus contribute to the reduction of false positive findings and reduce the recall and core biopsy rate in population-based screening. Phase-contrast CT may further be used to assist during histopathological workup, offering a 3D view of the tumor and helping to identify diagnostically valuable tissue sections within large tumors.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Fibroadenoma/diagnóstico por imagem , Interferometria/métodos , Tomografia Computadorizada por Raios X/métodos , Feminino , Humanos
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