Density Grade Research Articles

Breast Density Estimation with Fully Automated Volumetric Method:: Comparison to Radiologists' Assessment by BI-RADS Categories

The objective of our study was to calculate mammographic breast density with a fully automated volumetric breast density measurement method and to compare it to breast imaging reporting and data system (BI-RADS) breast density categories assigned by two radiologists. A total of 476 full-field digital mammography examinations with standard mediolateral oblique and craniocaudal views were evaluated by two blinded radiologists and BI-RADS density categories were assigned. Using a fully automated software, mean fibroglandular tissue volume, mean breast volume, and mean volumetric breast density were calculated. Based on percentage volumetric breast density, a volumetric density grade was assigned from 1 to 4. The weighted overall kappa was 0.895 (almost perfect agreement) for the two radiologists' BI-RADS density estimates. A statistically significant difference was seen in mean volumetric breast density among the BI-RADS density categories. With increased BI-RADS density category, increase in mean volumetric breast density was also seen (P < 0.001). A significant positive correlation was found between BI-RADS categories and volumetric density grading by fully automated software (ρ = 0.728, P < 0.001 for first radiologist and ρ = 0.725, P < 0.001 for second radiologist). Pairwise estimates of the weighted kappa between Volpara density grade and BI-RADS density category by two observers showed fair agreement (κ = 0.398 and 0.388, respectively). In our study, a good correlation was seen between density grading using fully automated volumetric method and density grading using BI-RADS density categories assigned by the two radiologists. Thus, the fully automated volumetric method may be used to quantify breast density on routine mammography.

Mammographic Breast Density Assessment Using Automated Volumetric Software and Breast Imaging Reporting and Data System (BIRADS) Categorization by Expert Radiologists

To investigate agreement on mammographic breast density (MD) assessment between automated volumetric software and Breast Imaging Reporting and Data System (BIRADS) categorization by expert radiologists. Forty cases of left craniocaudal and mediolateral oblique mammograms from 20 women were used. All images had their volumetric density classified using Volpara density grade (VDG) and average volumetric breast density percentage. The same images were then classified into BIRADS categories (I-IV) by 20 American Board of Radiology examiners. The results demonstrated a moderate agreement (κ = 0.537; 95% CI = 0.234-0.699) between VDG classification and radiologists' BIRADS density assessment. Interreader agreement using BIRADS also demonstrated moderate agreement (κ = 0.565; 95% CI = 0.519-0.610) ranging from 0.328 to 0.669. Radiologists' average BIRADS was lower than average VDG scores by 0.33, with their mean being 2.13, whereas the mean VDG was 2.48 (U = -3.742; P < 0.001). VDG and BIRADS showed a very strong positive correlation (ρ = 0.91; P < 0.001) as did BIRADS and average volumetric breast density percentage (ρ = 0.94; P < 0.001). Automated volumetric breast density assessment shows moderate agreement and very strong correlation with BIRADS; interreader variations still exist within BIRADS. Because of the increasing importance of MD measurement in clinical management of patients, widely accepted, reproducible, and accurate measures of MD are required.

Endothelial cell loss after phacoemulsification according to different anterior chamber depths measured by IOL master

PurposeTo compare the loss of corneal endothelial cells after phacoemulsification according to different anterior chamber depths (ACDs), as measured with the IOL Master.MethodsWe conducted a prospective, randomized clinical study on 135 eyes of 135 patients with senile cataracts. Eyes with nuclear density grades of 2 to 4 were divided into three groups according to ACD: ACD I, 1.5 &lt; ACD &lt; 2.5 mm; ACD II, 2.5 &lt; ACD &lt; 3.5 mm; or ACD III, 3.5 &lt; ACD &lt; 4.5 mm. Intraoperative ultrasound time (UST), mean cumulative dissipated energy (CDE), and balanced salt solution (BSS) use were measured. Clinical examinations included central corneal thickness (CCT), endothelial cell count (ECC), and corrected distance visual acuity (CDVA) preoperatively, and 1 day, 1 month, and 2 months postoperatively.ResultsThere were no significant differences in CDE among the ACD groups (P &gt; 0.05). The percentage of endothelial cell loss was significantly higher in ACD I than ACD III in the grade 3 and 4 cataract density groups 2 months after phacoemulsification (P &lt; 0.05). There were also more changes in CCT in all of the cataract density groups in the ACD I group compared to the ACD II and III groups 2 months postoperatively, but the difference was not statistically significant.ConclusionsEyes with shallow ACDs, especially those with relatively hard cataract densities, can be vulnerable to more corneal endothelial cell loss in phacoemulsification surgery. Thus, more attention is needed to avoid corneal decompensation in cataract surgery on patients with shallow ACDs and hard nucleus densities.

Predictors of improvement in semen parameters after varicocelectomy for male subfertility: A prospective study.

We aim to predict results of varicocelectomy on sperm density and progressive motility using preoperative clinical, laboratory and radiological data and to propose cut-off values for significant parameters. This prospective study was carried out between July 2011 and June 2014. We included 123 patients in our study. They were diagnosed with primary infertility with varicocele, were scheduled for varicocelectomy, and completed their follow-up. We excluded patients with azoospermia, total necrospermia, recurrent varicocele, and pituitary hormonal abnormalities. Varicocele was diagnosed and graded by physical examination and colour Doppler ultrasound. Semen analyses were completed preoperatively and 6 months postoperatively. Microscopic subinguinal varicocelectomy was done in all cases. Patient demographics, pre- and postoperative clinical data (varicocele grade and semen parameters) were statistically analyzed. The mean ± standard deviation of age, body mass index, and subfertility duration was 28.3 ± 7.4 years, 29.1 ± 2.7 kg/m(2), and 21.9 ± 7.1 months, respectively. About 53% of our patients (n = 66) had bilateral varicocele, and unilateral disease was found in the other 57 (46.3%) cases. Varicocele grade I was diagnosed in 42 (34.1%) patients, while the other 81 (65.9%) patients had grade II or III. Higher grades of varicocele, preoperative total testosterone level, sperm density, and progressive motility had a statistically significant impact on the outcome of varicocelectomy in univariate testing. Multivariate logistic analysis revealed that grade of preoperative varicocele (95% confidence interval [CI] 5.6-6.3, p = 0.007) and sperm density (95% CI 2.7-1.6, p = 0.0035), and progressive motility (95% CI 1.1-2.3, p = 0.0123) are independent predictors of semen parameters improvement after varicocelectomy. The grade of the varicocele, sperm density, and progressive motility are major predictors of outcome in varicocelectomy. Cut-off values of >8 million/mL and >18% for sperm density and progressive motility, respectively, in men with varicocele grade II or III, indicate a successful outcome.

Clinical Application of Diffusion-Weighted Magnetic Resonance Imaging in Uterine Cervical Cancer.

This study aimed to investigate the application value of apparent diffusion coefficient (ADC) values in evaluating histological type as well as pathologic grade of uterine cervical cancer; and to investigate whether ADC values could reflect tumor cellular density. Ninety-eight patients with histopathologically proven uterine cervical cancer were included in this study. Mean ADC value and minimum ADC value of the tumor were measured. Tumor cellular density was counted using colored multifunction imaging analyzing system. Both mean ADC value and minimum ADC value of squamous cell carcinoma were significantly lower than that of adenocarcinoma (P = 0.001; P = 0.000). Using mean ADC criteria (≤0.965 × 10⁻³ mm/s²) and minimum ADC criteria (≤0.844 × 10⁻³ mm/s²), the sensitivity and specificity for differentiating squamous cell carcinoma from adenocarcinoma were 83.5% and 76.9%, and 77.6% and 92.3%, respectively. Receiver operating characteristic analysis revealed that there was no statistically significant difference in the Az values between them (P = 0.990). Tumor cellular density, mean ADC value, and minimum ADC value of different pathological grade varied significantly (P = 0.000, P = 0.000, P = 0.000). There was a significant positive linear correlation between tumor cellular density and pathological grade of tumor (P = 0.000). Both mean ADC value and minimum ADC value correlated negatively with cellular density (P = 0.000, P = 0.000) and the pathological grade of tumor (P = 0.000, P = 0.000). Comparisons of correlation coefficients showed no significant differences (P = 0.656, P = 0.631). Diffusion-weighted magnetic resonance imaging has a potential ability to indicate the histologic type of uterine cervical cancer. Apparent diffusion coefficient measurements of uterine cervical cancer can represent tumor cellular density, thus providing a new method for evaluating the pathological grade of tumor.

Motor performance improvement via ArcelorMittal’s iCARe® electrical steel range for automotive applications

As previously reported [1-3], ArcelorMittal has a specific electrical steel product line for core laminations, which optimises the performance for automotive traction electrical machines. This iCARe® product family consists of Save grades allowing for higher efficiency, Torque grades allowing for higher torque density and Speed grades for high speed rotors. The iCARe® electrical steels now have been developed towards further loss reduction and polarisation increase. This paper shows the improved machine performance achievable by using these new iCARe® grades. Automotive traction machines require high power density, high efficiency and high torque, to maximise the powertrain’s performance and minimise the use of battery power. Permanent magnet synchronous machines (PMSM) are the preferred choice for electric and hybrid vehicles. When searching for cost reduction via eliminating the need for permanent magnets, wound rotor synchronous machines (WRSM) are an alternative. In this paper, a material comparison study is presented for both a PMSM and a WRSM having the same nominal speed and rated mechanical power. The reference case uses M330-35A electrical steel. The impact of switching to either Save or Torque grades of the latest generation is compared numerically: to determine the efficiency of each combination of machine topology and lamination type, the ArcelorMittal loss model is used [4], an extension of Bertotti’s loss model [5]. The impact of each grade is checked by varying the stack height whilst keeping the output power level constant. Hence the bill of materials is affected, reflecting the amount of active materials (laminations, magnets, windings) needed within each machine type, depending on the chosen electrical steel grade. The results show the efficiency benefits when using low loss Save grades and the torque density benefits when using Torque grades. Moreover, the new Torque grades with lower losses present a new potential for further machine performance enhancement: for instance the Torque 27 grade combines outstanding increase of torque density with high efficiency.

The general radiologist’s role in breast cancer risk assessment: breast density measurement on chest CT

To determine if general radiologists can accurately measure breast density on low-dose chest computed tomographic (CT) scans, two board-certified radiologists with expertise in mammography and CT scan interpretation, and seven general radiologists performed retrospective review of 100 women's low-dose chest CT scans. CT breast density grade based on Breast Imaging Reporting and Data System grades was independently assigned for each case. Kappa statistic was used to compare agreement between the expert consensus grading and those of the general radiologists. Kappa statistics were 0.61–0.88 for the seven radiologists, showing substantial to excellent agreement and leading to the conclusion that general radiologists can be trained to determine breast density on chest CT.

Mammographic density measurements are not affected by mammography system.

Mammographic density (MD) is a significant risk factor for breast cancer and has been shown to reduce the sensitivity of mammography screening. Knowledge of a woman's density can be used to predict her risk of developing breast cancer and personalize her imaging pathway. However, measurement of breast density has proven to be troublesome with wide variations in density recorded using radiologists' visual Breast Imaging Reporting and Data System (BIRADS). Several automated methods for assessing breast density have been proposed, each with their own source of measurement error. The use of differing mammographic imaging systems further complicates MD measurement, especially for the same women imaged over time. The purpose of this study was to investigate whether having a mammogram on differing manufacturer's equipment affects a woman's MD measurement. Raw mammographic images were acquired on two mammography imaging systems (General Electric and Hologic) one year apart and processed using VolparaDensity™ to obtain the Volpara Density Grade (VDG) and average volumetric breast density percentage (AvBD%). Visual BIRADS scores were also obtained from 20 expert readers. BIRADS scores for both systems showed strong positive correlation ([Formula: see text]; [Formula: see text]), while the VDG ([Formula: see text]; [Formula: see text]) and AvBD% ([Formula: see text]; [Formula: see text]) showed stronger positive correlations. Substantial agreement was shown between the systems for BIRADS ([Formula: see text]; [Formula: see text]), however, the systems demonstrated an almost perfect agreement for VDG ([Formula: see text]; [Formula: see text]).

Cytological Evaluation of Tongue Cells and Buccal Mucosa Cells

Objective: C-erbB-2 expression has been detected in 40 to 60% of head and neck squamous cell carcinomas (HNSCC). With regard to preneoplastic lesions, thus suggesting that the loss of CerbB-2 expression is a carcinogenic molecular event. Study Design: This study was conducted on a total of 20 paraffin-embedded HNSCC samples, which were histopathologically diagnosed at the Department of Pathology of medicine Hospital between 2010 and 2011. Paraffin-embedded HNSCC samples 3 mm in thickness, were then cut. The slides were stained with C-erbB-2. Results: There was significant relationship between staining density and differentiation grade (R1⁄4 0,922671). Conclusions: Consequently, it was concluded that cerbB-2 is a poor prognostic factor in HNSCC like in breast tumour.

The relationship between breast density and bone mineral density after menopause

[Purpose] The purpose of this study was to analyze the relationship between breast density and bone mineral density after menopause. [Subjects and Methods] The subjects were 130 patients who participated in a bone densitometry test and had a mammogram taken between January 1st, 2013 to October 1st, 2014. The mammograms were scored breast imaging-reporting and data system. Grade 1 indicates almost only fat, Grade 2 indicates fibroglandular densities, Grade 3 indicates heterogeneously dense tissue, and Grade 4 indicates an extreme density. Correlation analysis was carried out to investigate the relationship between breast density grades and bone mineral densities by age and body mass index. [Results] Breast density had a close relationship with age (−0.59), Body mass index (−0.39), and T-score (0.29). The results indicate that as age and body mass index increase, the grade of the breast density decreases, and as the T-score increases, the grade increases. [Conclusion] A precise evaluation of the of breast cancer risk associated with breast density should be conducted as a large scale prospective study for women in Korea.

Endothelial Cell Loss after Phacoemulsification according to Different Anterior Chamber Depths.

Purpose. To compare the loss of corneal endothelial cells after phacoemulsification according to different anterior chamber depths (ACDs). Methods. We conducted a prospective study on 135 eyes with senile cataracts. Eyes with nuclear density grades of 2 to 4 were divided into three groups according to ACD: ACD I, 1.5 < ACD ≤ 2.5 mm; ACD II, 2.5 < ACD ≤ 3.5 mm; or ACD III, 3.5 < ACD ≤ 4.5 mm. Intraoperative mean cumulative dissipated energy (CDE) was measured. Clinical examinations included central corneal thickness (CCT) and endothelial cell count (ECC) preoperatively and 2 months postoperatively. Results. There were no significant differences in CDE among the ACD groups (P > 0.05). Endothelial cell loss was significantly higher in ACD I than in ACD III in grades 3 and 4 cataract density groups 2 months after phacoemulsification (P < 0.05). There were also more changes in CCT in all of the cataract density groups in the ACD I group compared to the ACD II and III groups 2 months postoperatively, but the difference was not statistically significant. Conclusions. Eyes with shallow ACDs, especially those with relatively hard cataract densities, can be vulnerable to more corneal endothelial cell loss in phacoemulsification surgery.

Conjunctival impression cytology in patients with normal and impaired OSDI scores

PurposeTo describe goblet cell density and Nelson grading in different areas of the ocular surface using conjunctival impression cytology (CIC) among patients with normal and impaired Ocular Surface Disease Index (OSDI) scores. Materials and methodsPatients (n=166) under assessment for dry eye were recruited between 2011 and 2012 and classified according to the OSDI score in 4 categories (normal and impaired). Cytological study (CIC plus Papanicolaou staining) using the Nelson grading system, with modifications in staging, and goblet cell counting were performed on the nasal, temporal, inferior, and superior bulbar conjunctival surfaces. ResultsNelson grading was significantly higher in patients with a severely impaired OSDI score (1.41±0.14) compared to normal patients (0.86±0.09) (p<.01). Goblet cell density was significantly reduced in patients with a severely impaired OSDI score (310.24±56.24 cells per sample) compared with normal subjects (497.31±50.07 cells per sample) (p<.001). Compared with the photoexposed bulbar conjunctiva, goblet cell density on the non-photoexposed conjunctiva was significantly higher both in patients with mild (p<.01) and moderate (p<.001) OSDI scores. ConclusionPatients with severely impaired OSDI scores have less goblet cells and a higher Nelson grade. Goblet cells are more abundant on the non-photoexposed conjunctiva.

Calcination and characterisation studies of a Brazilian manganese ore tailing

This paper discusses the systematic analysis of the results of calcination as a function of size fraction performed on a sample of Brazilian silicate–carbonate manganese ore tailing at 800°C. The raw materials and the corresponding calcination products were analysed using several analytical techniques, including determination of density, specific surface area and porosity, chemical analysis and X-ray diffraction. The morphology and chemical composition of the calcination products were analysed by using scanning electronic microscopy equipped with energy-dispersive X-ray spectrometer (SEM/EDS). Results indicate that the manganese ore tailing consists of silicates, namely, spessartine (Mn3Al2(SiO4)3), tephroite (Mn2(SiO4)) and rhodonite ((Mn,Fe,Mg,Ca)5(SiO3)5) and rhodochrosite (MnCO3). The loss of CO2 and OH during the thermal decomposition of the carbonate (rhodochrosite and dolomite) and hydrated minerals (kaolinite, muscovite and antigorite) in air atmosphere at 800°C resulted in: (1) decrease of the specific surface area and porosity, (2) increase in the density and Mn grade from 27.6% to 32.2% and (3) increase in SiO2 grade from 26.7% to 30.1%. These results indicate that this material is within the chemical specifications of Fe–Si–Mn alloy.

A background decomposition method for domain integration in weak-form meshfree methods

An efficient technique is presented for evaluation of a domain integral in which the integrand is defined by its values at a discrete set of nodes with highly varying density. The proposed technique uses quadtree and octree techniques for 2D and 3D domains, respectively, so that the background of the integration domain can be divided into a few partitions with different grades of nodal density. The integrals over all partitions are then evaluated and added together to get the value of the whole-domain integral. Some numerical examples are given to show the accuracy and efficiency of the presented method.

Biomechanical evaluation of pedicle screw loosening mechanism using synthetic bone surrogate of various densities.

Pedicle screw fixation is a well-established procedure for various spinal disorders. However, pedicle screws failures are still reported. Therefore, there is a need for a greater understanding of the pedicle screw failure mechanism. This experimental study investigates the biomechanical stability of pedicle screws using a synthetic bone surrogate with a special focus on the screw loosening mechanism. Pedicle screws have been inserted in thirty six polyurethane foam blocks of three different densities. In half of the specimens from each density group, pedicle screws were submitted to cyclic bending (toggling) before pullout. The rest of specimens were solely loaded in axial pullout. The peak pullout force and stiffness were determined from load-displacement curve of each specimen. Statistical analyses were performed to investigate on the effect of toggling and bone surrogate density on the pedicle screw's pullout force. The results suggest that the pullout force and stiffness were significantly affected by toggling and density. Higher pullout forces resulted from higher grades of density. The proposed method allowed investigating the pedicle screw loosening mechanism. However, conducing further experimental tests on animal or cadaveric vertebrae are needed to confirm these findings.

Increased angiogenesis in primary myelofibrosis: latent transforming growth factor-β as a possible angiogenic factor.

ObjectiveThe aim of this work was to demonstrate a possible relationship between anti-latency-associated peptide human latent transforming growth factor beta 1 (latent TGF-β1) expression in megakaryocytes and microvascular density in bone marrow biopsies from patients with essential thrombocythemia and primary myelofibrosis.MethodsMicrovascular density was evaluated by immunohistochemical analysis and the expression of latent TGF-β1 in samples (100 megakaryocytes per bone marrow sample) from 18 essential thrombocythemia and 38 primary myelofibrosis (19 prefibrotic and 19 fibrotic) patients. Six bone marrow donor biopsies were used as controls. Fibrosis in the bone marrow biopsies was evaluated according to the European Consensus.ResultsThe average fibrosis grade differed between essential thrombocythemia and primary myelofibrosis groups when compared to the control group. Latent TGF-β1 expression differed significantly between the fibrotic primary myelofibrosis (PMF) group and the control group (p-value < 0.01). A high degree of neo-angiogenesis (demonstrated by analysis of CD34 expression) was detected in patients with myelofibrosis. There were correlations between latent TGF-β1 expression and microvascular density (r = 0.45; p-value < 0.0009) and between degree of microvascular density and fibrosis grade (r = 0.80; p-value < 0.0001). Remarkable differences for neo-angiogenesis were not observed between patients with essential thrombocythemia and controls.ConclusionAngiogenesis participates in the pathogenesis of primary myelofibrosis, in both the prefibrotic and fibrotic stages, while latent TGF-β is differentially expressed only in the prefibrotic stage.

Citología de impresión conjuntival en pacientes con valores OSDI normales y alterados

PurposeTo describe goblet cell density and Nelson grading in different areas of the ocular surface using conjunctival impression cytology (CIC) among patients with normal and impaired Ocular Surface Disease Index (OSDI) scores. Material and methodsPatients (n=166) under assessment for dry eye were recruited between 2011 and 2012 and classified according to the OSDI score in 4 categories (normal and impaired). Cytological study (CIC plus Papanicolaou staining) using the Nelson grading system, with modifications in staging, and goblet cell counting were performed on the nasal, temporal, inferior, and superior bulbar conjunctival surfaces. ResultsNelson grading was significantly higher in patients with a severely impaired OSDI score (1.41±0.14) compared to normal patients (0.86±0.09) (P<.01). Goblet cell density was significantly reduced in patients with a severely impaired OSDI score (310.24±56.24 cells per sample) compared with normal subjects (497.31±50.07 cells per sample) (P<.001). Compared with the photoexposed bulbar conjunctiva, goblet cell density on the non-photoexposed conjunctiva was significantly higher both in patients with mild (P<.01) and moderate (P<.001) OSDI scores. ConclusionPatients with severely impaired OSDI scores have less goblet cells and a higher Nelson grade. Goblet cells are more abundant on the non-photoexposed conjunctiva.

Treatment of chronic radiation proctopathy with radiofrequency ablation (with video)

Chronic radiation proctopathy (CRP) is a common sequela occurring even many years after pelvic radiation. Current ablative therapies for bleeding ectatic vessels have the potential for deep tissue injury leading to ulcerations, perforation, and fistulas. Radiofrequency ablation (RFA) therapy avoids deep tissue injury and is a promising treatment for CRP. To assess the long-term safety and efficacy of RFA for the treatment of CRP. Multicenter, retrospective analysis of a prospectively collected database. Veterans Affairs Boston Healthcare System, Massachusetts; Sarasota Memorial Hospital and Suncoast Endoscopy of Sarasota, Florida. A total of 39 consecutive patients with CRP. Endoscopic RFA of CRP. The primary endpoint of the study was complete resolution of rectal bleeding. Secondary endpoints included visually scored improvement of CRP on endoscopic follow-up by using a rectal telangiectasia density (RTD) grading score, improvement in hemoglobin level, and adverse events related to the procedure. A total of 39 male patients (mean [± standard deviation {SD}] age 72.9 ± 6.6 years) were included in the study. The mean number of RFA sessions was 1.49 (median 1, interquartile range [IQR] 1-2, range 1-4), with a mean interval of 18 weeks between sessions. Rectal bleeding stopped completely in all patients during the mean follow-up of 28 months (range 7-53 months). A significant improvement occurred in the mean (± SD) hemoglobin level from 11.8 ± 2 to 13.5 ± 1.6 g % (P< .0001). Endoscopic severity also improved significantly with an improvement in the median RTD score from 3 (IQR 2-3) to 0 (IQR 0-1) (P< .0001). Treatment with RFA led to discontinuation of blood transfusion and iron therapy in 92% and 82% patients, respectively. Retrospective analysis, lack of control group. RFA therapy led to complete resolution of rectal bleeding in all treated CRP patients, with improvement in clinical and endoscopic indices without any major adverse events. Further controlled studies are needed to establish RFA as the endoscopic therapy of choice for treatment of CRP.

High volumetric breast density predicts risk for breast cancer in postmenopausal, but not premenopausal, Korean Women.

We investigated the association between mammographic breast density and breast cancer risk in Korean women according to menopausal status and breast cancer subtypes. We enrolled 677 patients diagnosed with breast cancer and 1,307 healthy controls who participated in screening mammography at the National Cancer Center. Breast density was estimated using volumetric breast composition measurement. Of the total population, 1,156 (58.3 %) women were postmenopausal. The risk of breast cancer increased progressively with the increment of volumetric density grade (VDG) in postmenopausal women (p < 0.001). High breast density (VDG 4) was significantly associated with breast cancer compared with low breast density (VDG 1/2) regardless of body mass index. However, the association with parity and history of hormone replacement therapy (HRT) was only found in those with ≥2 children and those not receiving HRT. Breast density was positively associated with breast cancer risk regardless of histologic grade, tumor size, lymph node involvement, Ki67 index, and hormone receptor status. The association was more prominent in human epidermal growth factor receptor 2 (HER2)-positive tumors (VDG 1/2 vs. VDG 4 for HER2 normal, odds ratio [OR] 2.21, 95 % confidence interval [CI] 1.28-3.83, p < 0.001; for HER2 positive, OR 8.63, 95 % CI 3.26-22.83, p = 0.001; P heterogeneity = 0.030). However, no significant association was found between breast density and breast cancer risk in premenopausal women except for those with large-sized tumors (>2 cm) and a Ki67 index >15 %. High volumetric breast density is significantly associated with the risk of breast cancer in postmenopausal women; however, these relationships were not found in premenopausal women.

TU-F-18C-06: Which Women Based On Clinical Benefits and Dose Should Be Considered For Breast Screening with Tomosynthesis?

Purpose: To consider, on a patient specific basis according to volumetric breast density (VBD) the mean glandular dose (MGD) imparted by mammography and tomosynthesis so as to determine which women might benefit from tomosynthesis in consideration with the clinical benefits. Methods: For a set of 23 Hologic combo-mode images, MGD was calculated for the tomosynthesis and mammogram acquisitions, with glandularity derived from a personalised measure of VBD. The doses for each acquisition type were compared as a function of VBD, and correlated with breast thickness. Results: For dense breasts - precisely, those with a Volpara Density Grade (VDG) (analogous to BI-RADS) of 3 and 4 - the MGDs were approximately equal for both tomosynthesis and mammography. However, for low density breasts - those with a VDG of 1 and 2 - the MGD was significantly greater in the tomosynthesis examination than for the mammogram. The compressed breast thickness was generally greater for the lower density (VDG 1 and 2) breasts, than for higher density (VDG 3 and 4) breasts. Conclusion: In breasts of low VBD, examination by mammography offers a lower patient specific MGD than tomosynthesis, sometimes substantially. In breasts of high VBD, the MGD values are approximately equal. The lower MGD is likely due to the increased compressed breast thickness observed in the low density cases. This causes such images to be acquired at a higher MGD in tomosynthesis in order to obtain a satisfactory contrast-to-noise ratio. This results from fundamental differences in the characteristics of the function relating contrast-to-noise ratio to dose between the techniques. Since the possibility of lesion masking arising from tissue superposition is limited in low density breasts, clinicians need to consider the diagnostic benefits versus the apparent increased dose in fatty breasts, which will remain even if the 2D component is stopped. Volpara Solutions Ltd market software for measuring volumetric breast density (Volpara Density), and measuring personalised mean glandular dose (Volpara Dose).