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Item does not contain fulltext Breast computed tomography (BCT) is an emerging application of X-ray tomography in radiological practice. A few clinical prototypes are under evaluation in hospitals and new systems are under development aiming at improving spatial and contrast resolution and reducing delivered dose. At the same time, synchrotron-radiation phase-contrast mammography has been demonstrated to offer substantial advantages when compared with conventional mammography. At Elettra, the Italian synchrotron radiation facility, a clinical program of phase-contrast BCT based on the free-space propagation approach is under development. In this paper, full-volume breast samples imaged with a beam energy of 32 keV delivering a mean glandular dose of 5 mGy are presented. The whole acquisition setup mimics a clinical study in order to evaluate its feasibility in terms of acquisition time and image quality. Acquisitions are performed using a high-resolution CdTe photon-counting detector and the projection data are processed via a phase-retrieval algorithm. Tomographic reconstructions are compared with conventional mammographic images acquired prior to surgery and with histologic examinations. Results indicate that BCT with monochromatic beam and free-space propagation phase-contrast imaging provide relevant three-dimensional insights of breast morphology at clinically acceptable doses and scan times.

In the medical literature, the role of breastfeeding and reproductive factors in the risk of breast carcinoma is still an open debate in premenopausal women. We highlight the role of breastfeeding and reproductive factors in luminal A and luminal B, the most frequent breast cancers. This case-control study analyzes a White premenopausal population of 286 breast cancer patients, divided into molecular subtypes, and 578 controls matched by age. Multivariate logistic regression models were used to assess the relationships of breastfeeding and other reproductive factors (age at menarche, parity, age at first pregnancy, number of children) with the risk of breast cancers. Among the variables examined, reproductive factors did not alter the risk of cancer, whereas breastfeeding up to 12 months was a significant protective factor against luminal B breast cancer (multivariate odds ratio: 0.22, 95% confidence interval: 0.09-0.59, P=0.002). In contrast, luminal A cases did not significantly correlate with breastfeeding or other reproductive factors. Breastfeeding up to 12 months is strongly protective against the more aggressive luminal B, but not against the less aggressive luminal A breast cancer in premenopausal White women.

A Phase-Contrast breast CT facility based on a high-resolution CdTe photon-counting detector is under development at Elettra, the Italian Synchrotron Radiation (SR) facility in Trieste. The CT system exploits propagation-based phasecontrast imaging and phase-retrieval algorithm. The voxel size is 57×57×50 μm3 and the delivered MGDs, about 5 mGy, are comparable with clinical breast CT systems. In the present contribution, the comparisons between histological breast cancers and full breast CT images are presented from samples of breast mastectomy. The high resolution of the breast CT images and low noise due to the phase contrast allow a very fine matching between X-ray CT and histology at acceptable delivered doses.

A quantitative characterization of the soft tissues composing the human breast is achieved by means of a monochromatic CT phase-contrast imaging system, through accurate measurements of their attenuation coefficients within the energy range of interest for breast CT clinical examinations. Quantitative measurements of linear attenuation coefficients are performed on tomographic reconstructions of surgical samples, using monochromatic x-ray beams from a synchrotron source and a free space propagation setup. An online calibration is performed on the obtained reconstructions, in order to reassess the validity of the standard calibration procedure of the CT scanner. Three types of healthy tissues (adipose, glandular, and skin) and malignant tumors, when present, are considered from each sample. The measured attenuation coefficients are in very good agreement with the outcomes of similar studies available in the literature, although they span an energy range that was mostly neglected in the previous studies. No globally significant differences are observed between healthy and malignant dense tissues, although the number of considered samples does not appear sufficient to address the issue of a quantitative differentiation of tumors. The study assesses the viability of the proposed methodology for the measurement of linear attenuation coefficients, and provides a denser sampling of attenuation data in the energy range useful to breast CT.

In this study we demonstrate the first direct comparison between synchrotron x-ray propagation-based CT (PB-CT) and cone-beam breast-CT (CB-CT) on human mastectomy specimens (N = 12) including different benign and malignant lesions. The image quality and diagnostic power of the obtained data sets were compared and judged by two independent expert radiologists. Two cases are presented in detail in this paper including a comparison with the corresponding histological evaluation. Results indicate that with PB-CT it is possible to increase the level of contrast-to-noise ratio (CNR) keeping the same level of dose used for the CB-CT or achieve the same level of CNR reached by CB-CT at a lower level of dose. In other words, PB-CT can achieve a higher diagnostic potential compared to the commercial breast-CT system while also delivering a considerably lower mean glandular dose. Therefore, we believe that PB-CT technique, if translated to a clinical setting, could have a significant impact in improving breast cancer diagnosis.

Item does not contain fulltext Two dosimetric quantities [mean glandular dose (MGD) and entrance surface air kerma (ESAK)] and the diagnostic performance of phase-contrast mammography with synchrotron radiation (MSR) are compared to conventional digital mammography (DM). Seventy-one patients (age range, 41 to 82 years) underwent MSR after a DM examination if questionable or suspicious breast abnormalities were not clarified by ultrasonography. The MGD and the ESAK delivered in both examinations were evaluated and compared. Two on-site radiologists rated the images in consensus according to the Breast Imaging Reporting and Data System assessment categories, which were then correlated with the final diagnoses by means of statistical generalized linear models (GLMs). Receiver operating characteristic curves were also used to assess the diagnostic performance by comparing the area under the curve (AUC). An important MGD and ESAK reduction was observed in MSR due to the monoenergetic beam. In particular, an average 43% reduction was observed for the MGD and a reduction of more than 50% for the ESAK. GLM showed higher diagnostic accuracy, especially in terms of specificity, for MSR, confirmed by AUC analysis ([Formula: see text]). The study design implied that the population was characterized by a high prevalence of disease and that the radiologists, who read the DM images before referring the patient to MSR, could have been influenced in their assessments. Within these limitations, the use of synchrotron radiation with the phase-contrast technique applied to mammography showed an important dose reduction and a higher diagnostic accuracy compared with DM. These results could further encourage research on the translation of x-ray phase-contrast imaging into the clinics.

The aim of this study was to highlight the advantages that propagation-based phase-contrast computed tomography (PB-CT) with synchrotron radiation can provide in breast cancer diagnostics. For the first time, a fresh and intact mastectomy sample from a 60 year old patient was scanned on the IMBL beamline at the Australian Synchrotron in PB-CT mode and reconstructed. The clinical picture was described and characterized by an experienced breast radiologist, who underlined the advantages of providing diagnosis on a PB-CT volume rather than conventional two-dimensional modalities. Subsequently, the image quality was assessed by 11 breast radiologists and medical imaging experts using a radiological scoring system. The results indicate that, with the radiation dose delivered to the sample being equal, the accuracy of a diagnosis made on PB-CT images is significantly higher than one using conventional techniques.

Interval breast cancers (IBC) have been of great concern since breast mammogram screening programs were introduced. We compared IBC to screen-detected cancers (SDC). IBC accounted for one-fifth of all breast cancers diagnosed in women who followed the regional screening program. IBC appeared to be more aggressive than SDC in terms of tumor invasiveness, size, and St Gallen molecular subtype, leading to worse overall and disease-free survival. Background: The introduction of breast screening programs has raised the problem of interval breast cancers (IBC). The aims of this study were to analyze the impact of IBC on the screening program, to compare IBC and screendetected cancers (SDC), and to identify possible predictors of mortality. Patients and Methods: Patients with breast cancer diagnosed during the regional breast screening program between January 2008 and December 2013 at a single center in Italy were included. Demographic, preoperative, and postoperative data were prospectively collected and retrospectively analyzed. Results: Five hundred thirty-four patients were enrolled; 106 women (19.9%) had IBC and 428 women (80.1%) SDC. IBC presented more aggressive features compared to SDC, such as tumor invasiveness (95% vs. 85%; P ¼ .005), tumor size ( pT2 37% vs. 21%; P ¼ .001), grade (G3 39% vs. 17%; P < .001), and St Gallen molecular subtype (triple negative 22% vs. 7%; P < .001), resulting in higher distant recurrence rate (8% vs. 2%; P ¼ .009) and worse overall and disease-free survival (P ¼ .03 and P ¼ .001, respectively). Cox multivariate regression analysis identified St Gallen molecular subtype as the only predictor of mortality in patients with breast cancer (P ¼ .03). Conclusion: IBC accounted for one-fifth of all breast cancers diagnosed in women who followed the regional screening program. Furthermore, IBC appeared to have more aggressive features compared to SDC, leading to worse survival. These worse survivals depended on St Gallen molecular subtype.

The aim of this study was to evaluate the feasibility of phase-contrast mammography with synchrotron radiation using a high-resolution computed radiology (CR) system devoted to mammography.The study was performed at the Synchrotron Radiation for Medical Physics (SYRMEP) beamline of the Elettra synchrotron radiation (SR) facility in Trieste (Italy); X-ray beams were in the range 16-22 keV with a high degree of monochromaticity and spatial coherence. The CR system evaluated is the FCR Profect CS by Fujifilm Global. The first images were obtained from test objects and surgical breast specimens. Images obtained using SR and both screen-film and the CR system were compared with images of the same samples acquired with digital mammography equipment. In view of the good quality of the results obtained, the CR system was used in two mammographic examinations with SR.Images acquired using SR and both screen-film and CR were obtained with the same level of delivered dose. Image quality obtained with CR was similar or superior to that of screen-film images. Moreover, the digital images obtained with SR were always better than those acquired using the digital mammography system.Phase-contrast mammography with SR using the studied CR system is a feasible option.

Introduzione: Il riconoscimento intra-operatorio delle metastasi nel linfonodo sentinella, in pazienti affetti da cancro della mammella, è utile al fine di procedere ad una linfoadenectomia ascellare immediata nel corso del medesimo intervento. Ciò è fondamentale per evitare una terapia adiuvante tardiva ed un incremento della morbilità e dei costi sanitari. Scopo di tale lavoro è dimostrare che, la metodica citologica “touch-imprint” (TIC), utilizzata presso l’ Azienda Ospedaliero-Universitaria di Trieste, risponde a tale necessità e nel contempo valutarne l’affidabilità. Materiali e metodi: Nel periodo 2009-2012, presso la nostra struttura sono stati operati 690 carcinomi mammari, di cui 479 (69.4%) sono stati selezionati per la ricerca del linfonodo sentinella con radiocolloide. In 347 carcinomi di dimensioni inferiori o uguali a T2 è stata eseguita la metodica citologica TIC; il linfonodo sentinella è stato successivamente sottoposto all’ analisi istologica standard (sezioni seriate ogni 100 micron per ematossilina-eosina e immunoistochimica) che è stato assunta come “gold standard”. Risultati: Su 347 TIC 298 casi erano concordanti con la diagnosi istologica (38 veri positivi e 260 veri negativi). Dei 49 casi risultati falsi negativi, l’analisi definitiva ha dimostrato 28 casi di micrometastasi e 21 casi di macrometastasi, mentre dei 38 casi positivi al TIC, 35 risultavano macrometastasi, 2 micrometastasi e 1 caso di cellule tumorali isolate. La sensibilità e specificità del TIC per macrometastasi sono rispettivamente 64.4% e 100%. Solo 29 casi su 347, pari all’ 8.3%, sono stati sottoposti a radicalizzazione ascellare differita, mentre nel periodo 2005-2008, prima dell’introduzione del TIC,utilizzando l’analisi istologica standard del linfonodo sentinella, tale percentuale era del 18.2%. Discussione e conclusioni: Grazie alla metodica TIC il tasso di dissezioni ascellari in differita è diminuito notevolmente (dal 18.2% all’8.3%). Se gli studi, in corso di validazione definitiva, dimostreranno che la linfoadenectomia ascellare nel trattamento delle micrometastasi non è necessaria, si può ipotizzare che il numero di reinterventi sull’ascella possa ulteriormente ridursi. Nella nostra esperienza, grazie alla discreta sensibilità del TIC per le macrometastasi legata all’ ottima confidenza del patologo con i preparati citologici, è stato possibile migliorare in maniera rilevante l’approccio chirurgico sull’ascella ed il timing oncologico, senza impegno aggiuntivo di risorse economiche.

Introduction The first clinical trial of phase-contrast mammography with monochromatic beam was performed at Elettra, the Italian Synchrotron Radiation facility. A lower Mean Glandular Dose (MGD) and a higher specificity were achieved compared to the digital mammography for the patient cohort (more than 70). Purpose The SYRMA-CT project (SYnchrotron Radiation for MAmmography – Computed Tomography) aims to perform the first clinical trial of phase-sensitive breast CT with monochromatic beam. High image quality and low dose are expected according to the results of the first mammography trial. Materials and methods A large area CdTe single photon counting detector (PIXIRAD-8) is used. Phase-retrieval algorithm are applied, thus exploiting propagation based phase-contrast imaging (PPCI). The dose system of the beamline has been calibrated to match the energy requirement up to 40 keV. Due to the peculiar irradiation modality, ad hoc Monte Carlo simulations and experimental measurements were performed for dose evaluation. Results Images of surgical samples included in large test objects (up to 12 cm diameter) were acquired at 38 keV in clinical compatible dose conditions (MGD ∼5 mGy). Phase-retrieval pre-processing was applied improving the CNR of the high-resolution images with (120 μm) 3 voxel size. Conclusion The upgrade of the mammographic facility of the Elettra laboratory towards a new clinical trial is going on. Image quality and dose assessment indicate its feasibility with monochromatic beam. This clinical trial will allow the evaluation of PPCI breast CT in optimal conditions and will give indication for the translation to the hospital of phase-sensitive techniques. Disclosure Nothing to declare.

We present the outcomes of combined feasibility studies carried out at Elettra and Australian Synchrotron to evaluate novel protocols for threedimensional (3D) mammographic phase contrast imaging. A custom designed plastic phantom and some tissue samples have been studied at diverse resolution scales and experimental conditions. Several computed tomography (CT) reconstruction algorithms with different pre-processing and post-processing steps have been considered. Special attention was paid to the effect of phase retrieval on the diagnostic value of the reconstructed images. The images were quantitatively evaluated using objective quality indices in comparison with subjective assessments performed by three experienced radiologists and one pathologist. We show that the propagation-based phase-contrast imaging (PBI) leads to substantial improvement to the contrast-to-noise and to the intrinsic quality of the reconstructed CT images compared with conventional techniques as well as to an important reduction of the delivered doses, thus opening the way to clinical implementations.

The synchrotron radiation (SR) clinical mammography, using as detector a commercial screen-film system, is a further crucial step of the SYRMEP (Synchrotron Radiation for Medical Physics) Project. In March and April of this year, mammographic examinations on nine patients have been carried out with X-rays from ELETTRA, the SR laboratory in Trieste, Italy. The facility for Phase Contrast (PhC) SR mammography is now operative in patient mode and is used for patient examinations, producing breast images in different projections. The entire procedure is automated and is able to achieve the correct exposure on the film taking into consideration the requested limits on the applied dose, as a function of the thickness and glandularity of the breast. The SR mammography shows a higher spatial resolution and contrast detail visibility, in comparison with the conventional analog or digital mammography, with a comparable or lower dose. In some cases of these first nine patients, the radiologists have clarified the ambiguity of the previous examinations. These preliminary results are encouraging and a complete evaluation of the clinical impact of the new method is in progress.

To prospectively evaluate the diagnostic contribution of mammography with synchrotron radiation in patients with questionable or suspicious breast abnormalities identified at combined digital mammography (DM) and ultrasonography (US).The ethics committee approved this prospective study, and written informed consent was obtained from all patients. Mammography with synchrotron radiation was performed with a phase-detection technique at a synchrotron radiation laboratory. Forty-nine women who met at least one of the inclusion criteria (palpable mass, focal asymmetry, architectural distortion, or equivocal or suspicious mass at DM; none clarified at US) were enrolled. Forty-seven women (mean age, 57.8 years ± 8.8 [standard deviation]; age range, 43-78 years) completed the study protocol, which involved biopsy or follow-up for 1 year as the reference standard. Breast Imaging Reporting and Data System (BI-RADS) scores of 1-3 were considered to indicate a negative result, while scores 4-5 were considered to indicate a positive result. The visibility of breast abnormalities and the glandular parenchymal structure at DM and at mammography with synchrotron radiation was compared by using the Wilcoxon signed rank test.In 29 of the 31 patients with a final diagnosis of benign entity, mammography with synchrotron radiation yielded BI-RADS scores of 1-3. In 13 of the remaining 16 patients with a final diagnosis of malignancy, mammography with synchrotron radiation yielded BI-RADS scores of 4-5. Therefore, a sensitivity of 81% (13 of 16 patients) and a specificity of 94% (29 of 31 patients) were achieved with use of the described BI-RADS dichotomization system.These study results suggest that mammography with synchrotron radiation can be used to clarify cases of questionable or suspicious breast abnormalities identified at DM.http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11100745/-/DC1.

The purpose of this study is evaluation of therapeutic impact of magneti c resonance imaging (MRI) in breast cancer patients that cannot be imaged adequately with traditional radiology: dense breasts, microcalcifications suspicious for carcinoma in situ or discordance between mammography and ultra-sound. A review was performed of 493 patients' records: determination of breast MRI effect on c1inical management was made for the selected 70 cases by analysing pre-MRI and post-MRI therapeutic pia ns. Analysis of final pathology was useful to determine if the change in surgical pian prompted by MRI was appropriate. Breast MRI added c1inical information in 52.9% of patients that resulted in 44.3% of management changes that were judged as appropriate in 83.9% of cases. Breast MRI provides additional useful formation, but causes more extensive surgery (40%) with no proven prognostic benefit. MRI should be considered optional in the c1inical staging of breast cancer and performed in selected cases. © 2009 Eisevier Ltd. Ali rights reserved.

A clinical program for X-ray phase contrast (PhC) mammography with synchrotron radiation (SR) has been started in March 2006 at the SYRMEP beamline of Elettra, the SR facility in Trieste, Italy. The original beamline layout has been modified substantially and a clinical facility has been realized. In order to fulfill all security requirements, dedicated systems have been designed and implemented, following redundancy criteria and “fail safe” philosophy. Planar radiographic images are obtained by scanning simultaneously the patient and the detector through the stationary and laminar SR beam. In this first phase of the project a commercial screen-film system has been used as image receptor. Upon approval by the respective authorities, the mammography program is about half way to conclusion. Up to now about 50 patients have been examined. The patients are volunteers recruited by the radiologist after conventional examinations at the hospital resulted in an uncertain diagnosis. As an example one case of PhC SR mammography is shown and compared to conventional digital mammography. Preliminary analysis shows the high diagnostic quality of the PhC SR images that were acquired with equal or less delivered dose compared to the conventional ones. © 2008 Elsevier Ireland Ltd. All rights reserved.

Purpose: The first clinical facility for synchrotron radiation (SR) mammography is now operative at the SYRMEP beamline of ELETTRA, the SR facility in Trieste, Italy. The mammographic facility and the preliminary results of the clinical trial are presented in this contribution. Method and Materials: The distance between the SR source and the patient is about 30 m; the main features of the X-ray beam are: monochromaticity at ~0.2% bandwith in the energy range 8-35 keV, photon flux of about 10 8 ph/(mm 2 s) and dimensions of 21 cm x 3.5 mm at the compressed breast. An innovative dosimetric system allows the on-line dose control during the examination. The images are acquired by scanning the patient, in prone position, in front of the stationary laminar beam; the average scanning time is about 10 s. The detector is a screen film system; it is at ~2 m from the breast in order to fulfil the so-called Phase Contrast (PhC) requirements. The breast thickness and glandularity defines the optimal beam energy for each examination. The patients are enrolled by radiologists, after routine examinations, on the basis of BI-RADS classification, according the research program approved by the local Ethical Committee. Results: This communication concerns the first 9 patients underwent the SR PhC mammography; the images match the quality obtained in previous in vitro studies. With reference to conventional mammography the diagnostic quality of the radiological images is better, without increasing the delivered dose to the patient.

For several years a large variety of in‐vitro medical imaging studies were carried out at the SYRMEP (Synchrotron Radiation for Medical Physics) beamline of the synchrotron radiation facility ELETTRA (Trieste, Italy) utilizing phase sensitive imaging techniques. In particular low dose Phase Contrast (PhC) in planar imaging mode and computed tomography were utilized for full field mammography. The results obtained on in‐vitro samples at the SYRMEP beamline in PhC breast imaging were so encouraging that a clinical program on a limited number of patients selected by radiologists was launched to validate the improvements of synchrotron radiation in mammography. PhC mammography with conventional screen‐film systems is the first step within this project. A digital system is under development for future applications. During the last years the entire beamline has been deeply modified and a medical facility dedicated to in‐vivo mammography was constructed. The facility for PhC synchrotron radiation mammography is now operative in patient mode. The system reveals a prominent increase in image quality with respect to conventional mammograms even at lower delivered dose.

Results are presented of a feasibility study of three-dimensional X-ray tomographic mammography utilising in-line phase contrast. Experiments were performed at SYRMEP beamline of Elettra synchrotron. A specially designed plastic phantom and a mastectomy sample containing a malignant lesion were used to study the reconstructed image quality as a function of different image processing operations. Detailed evaluation and optimization of image reconstruction workflows have been carried out using combinations of several advanced computed tomography algorithms with different pre-processing and post-processing steps. Special attention was paid to the effect of phase retrieval on the diagnostic value of the reconstructed images. A number of objective image quality indices have been applied for quantitative evaluation of the results, and these were compared with subjective assessments of the same images by three experienced radiologists and one pathologist. The outcomes of this study provide practical guidelines for the optimization of image processing workflows in synchrotron-based phase-contrast mammo-tomography.

The main purpose of the SYRMEP (SYnchrotron Radiation for MEdical Physics) research team is the investigation and development of innovative techniques for medical imaging. A dedicated beamline has been built at ELETTRA to evaluate the effectiveness of synchrotron-based techniques in medical radiology with particular interest to mammography, and more in general, to the imaging of biological and biomedical samples, either in planar or tomographic set-ups. Taking advantage of the high intensity and high spatial coherence of Synchrotron Radiation (SR), phase sensitive techniques such as Phase Contrast (PhC) and Diffraction Enhanced Imaging (DEI) can be applied. After successful studies carried out on test objects and in vitro samples, the research in mammography is aiming at in vivo clinical trials. For this purpose, the layout of the SYRMEP beamline has been substantially modified and the safety system has been completely redesigned to guarantee the compliance with current radiation protection guidelines. In the present paper, the main characteristics of the beamline and an overview of the results obtained in different contexts of biomedical imaging are presented. Moreover, the status of the project for clinical mammography is outlined.