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Papers by catherine klifa

Research paper thumbnail of Intake of dietary carbohydrates in early adulthood and adolescence and breast density among young women

Cancer causes & control : CCC, 2018

Carbohydrate intake increases postprandial insulin secretion and may affect breast density, a str... more Carbohydrate intake increases postprandial insulin secretion and may affect breast density, a strong risk factor for breast cancer, early in life. We examined associations of adolescent and early adulthood intakes of total carbohydrates, glycemic index/load, fiber, and simple sugars with breast density among 182 young women. Diet was assessed using three 24-h recalls at each of five Dietary Intervention Study in Children (DISC) clinic visits when participants were age 10-19 years and at the DISC06 Follow-Up Study clinic visit when participants were age 25-29 years. Associations between energy-adjusted carbohydrates and MRI-measured percent dense breast volume (%DBV) and absolute dense breast volume (ADBV) at 25-29 years were quantified using multivariable-adjusted mixed-effects linear models. Adolescent sucrose intakes and premenarcheal total carbohydrates intakes were modestly associated with higher %DBV (mean %DBV, 16.6 vs 23.5% for sucrose; and 17.2 vs 22.3% for premenarcheal tot...

Research paper thumbnail of Quantification of breast tissue index from MR data using fuzzy clustering

The 26th Annual International Conference of the IEEE Engineering in Medicine and Biology Society

The study objective was to develop a segmentation technique to quantify breast tissue and total b... more The study objective was to develop a segmentation technique to quantify breast tissue and total breast volume from magnetic resonance imaging (MRI) data to obtain a breast tissue index (BTI) related to breast density. Our goal is to quantify MR breast density to improve breast cancer risk assessment for certain high-risk populations for whom mammography is of limited usefulness due to high breast density. A semi-automatic 3D segmentation technique was implemented based on a fuzzy c-means technique (FCM) to segment fibroglandular tissue from fat in the breast images. After validation on a phantom, our FCM technique was first used to test the breast tissue measures reproducibility in two consecutive MR examinations of the same patients. The technique was then applied to measure the BTI on 10 high-risk patients. Results of BTI obtained with the semi-automated FCM method were compared with BTI results for the same patients using two other techniques, manual delineation and global threshold. BTI measures correlated well with mammographic densities (Pearson coefficients r = 0.78 using MR manual delineation, and r = 0.75 using MR FCM). The breast tissue index could therefore become a common measure for future studies of using noncontrast MRI data.

Research paper thumbnail of 2048: Breast Magnetic Resonance Imaging (MRI) Enhancement Beyond the Tumor Margin: Is There An Association With Treatment Response?

breast tissue (chest wall, pectoralis and lung). A dose of 38.5 Gy to the PTV_EVAL was planned in... more breast tissue (chest wall, pectoralis and lung). A dose of 38.5 Gy to the PTV_EVAL was planned in 10 fractions. A 5 cm jaw length and a pitch of 0.215 were used for planning. The doses to the ipsilateral breast, contralateral breast, heart, and both lungs were restricted during plan optimization to meet protocol guidelines. The treatment time and PTV_EVAL doses are reported. Results: Table 1 lists the average (range) of volumes that received the allowable dose according to protocol. For various structures, the RTOG volume limits are based on the percentage of the prescription dose (PD) that is allowed to a percentage volume. The second row lists the allowable volume limit. The third row lists the average and range of volumes that received the dose limit. In all cases, the maximum dose to the contralateral lung was Ͻ3% of the prescription dose. The average (range) treatment time was 10 (7-14) minutes. In 9 of the 10 cases, all PTV_EVAL and sensitive structure volume limits were acceptable (i.e. within 5% of specified value). In one right-sided case, the contralateral lung volume to 5% of the PD was 40% and the respective heart volume was 60%. This PTV_EVAL was located medially and dose limits to the contra lateral breast likely compromised the delivery. A solution with helical tomotherapy could be theoretically found with this particular situation, however, treatment times exceeded practical limits. Conclusions: In the large majority of patients, partial breast treatment helical tomotherapy plans were acceptable by RTOG Protocol 0413 guidelines. Although not the focus of the present study, megavoltage CT scanning prior to each fraction would also add the benefit of daily visualization and localization of the seroma, i.e. the tumor bed (Langen et al, IJROBP, 63S, p. S179, 2005), thus potentially allowing a decrease in treatment margins. Partial breast accelerated irradiation is feasible with helical tomotherapy delivery.

Research paper thumbnail of Study of Breast Tissue Composition Using Magnetic Resonance Imaging and Diffuse Optical Spectroscopy

Biomedical Optics, 2006

Abstract We combined Magnetic Resonance Imaging (MRI) and Diffuse Optical Spectroscopy (DOS) to s... more Abstract We combined Magnetic Resonance Imaging (MRI) and Diffuse Optical Spectroscopy (DOS) to study breast tissue composition in 20 healthy volunteers. A combination of MRI and DOS measures was found to be associated with breast density.

Research paper thumbnail of Characterization of breast lesions using the 3D FIESTA sequence and contrast-enhanced magnetic resonance imaging

Journal of Magnetic Resonance Imaging, 2007

Purpose: To determine whether combining 3D fast imaging employing steady-state acquisition (FIEST... more Purpose: To determine whether combining 3D fast imaging employing steady-state acquisition (FIESTA) and T1weighted contrast-enhanced (CE) sequences could help characterize lesions in 32 women with benign, in situ, or invasive breast lesions. Since FIESTA provides both T1 and T2 information on the same three-dimensional (3D) matrix as high-resolution T1-weighted dynamic data, we aimed to verify whether invasive lesions could be separated from in situ and/or benign lesions using quantitative FIESTA measures of tissue intensity and homogeneity. Material and Methods: With the use of CE-MRI data, regions of interest (ROIs) were manually delineated in enhancing lesions and on surrounding normal tissue. These ROIs were then applied to 3D FIESTA data. Quantitative measures between lesion and normal tissue were compared among the lesion groups. Results: On FIESTA most invasive cancer lesions were hypointense compared to surrounding normal tissue (mean lesion intensity was 89% of normal tissue intensity), whereas most ductal and benign lesions appeared hyperintense compared to surrounding normal tissue (lesions at 100.9% and 121.9% of normal tissue intensity, respectively). Measures obtained from resampled T2-weighted data showed no significant differences between the invasive and benign lesion groups. Conclusion: We detected significant differences between invasive and noninvasive lesions by quantifying intensity differences between the lesions and surrounding normal tissue on FIESTA.

Research paper thumbnail of Menstrual and reproductive characteristics and breast density in young women

Cancer Causes & Control, 2013

Purpose-Breast density is strongly related to breast cancer risk, but determinants of breast dens... more Purpose-Breast density is strongly related to breast cancer risk, but determinants of breast density in young women remain largely unknown.

Research paper thumbnail of Reconstruction 3D de defauts en radiographie industrielle

Certains matériels des centrales nucléaires soumis à de fortes contraintes sont contrôlés réguliè... more Certains matériels des centrales nucléaires soumis à de fortes contraintes sont contrôlés régulièrement par radiographies X ou gamma afin de vérifier leur intégrité. Or l'information donnée par un film radiographique ne permet pas de connaître l'orientation d'un défaut dans une pièce. L'étude consiste à reconstruire ces défauts dans l'espace 3D connaissant trois de leurs projections radiographiques. L'algorithme mis au point combine une reconstruction algébrique ART et une modélisation du volume 3D par des champs markoviens.

Research paper thumbnail of Reliability of the apparent diffusion coefficient assessment of cervical lymph nodes in phantoms and healthy volunteers

Poster: "ECR 2018 / C-0591 / Reliability of the apparent diffusion coefficient assessment of... more Poster: "ECR 2018 / C-0591 / Reliability of the apparent diffusion coefficient assessment of cervical lymph nodes in phantoms and healthy volunteers" by: "A. Iannessi1, H. Beaumont2, B. MOREAU1, C. Hoog1, C. Klifa2; 1Nice/FR, 2Valbonne/FR"

Research paper thumbnail of Pubertal timing and breast density in young women: a prospective cohort study

Breast Cancer Research, 2019

Background Earlier age at onset of pubertal events and longer intervals between them (tempo) have... more Background Earlier age at onset of pubertal events and longer intervals between them (tempo) have been associated with increased breast cancer risk. It is unknown whether the timing and tempo of puberty are associated with adult breast density, which could mediate the increased risk. Methods From 1988 to 1997, girls participating in the Dietary Intervention Study in Children (DISC) were clinically assessed annually between ages 8 and 17 years for Tanner stages of breast development (thelarche) and pubic hair (pubarche), and onset of menses (menarche) was self-reported. In 2006–2008, 182 participants then aged 25–29 years had their percent dense breast volume (%DBV) measured by magnetic resonance imaging. Multivariable, linear mixed-effects regression models adjusted for reproductive factors, demographics, and body size were used to evaluate associations of age and tempo of puberty events with %DBV. Results The mean (standard deviation) and range of %DBV were 27.6 (20.5) and 0.2–86.1...

Research paper thumbnail of Abstract 3262: Biomarkers of response to deslorelin in women at high risk of breast cancer

Prevention Research, 2018

Research paper thumbnail of Discrepancies of assessments in a RECIST 1.1 phase II clinical trial – association between adjudication rate and variability in images and tumors selection

Cancer Imaging, 2018

Background: In imaging-based clinical trials, it is common practice to perform double reads for e... more Background: In imaging-based clinical trials, it is common practice to perform double reads for each image, discrepant interpretations can result from these two different evaluations. In this study we analyzed discrepancies that occurred between local investigators (LI) and blinded independent central review (BICR) by comparing readerselected imaging scans and lesions. Our goal was to identify the causes of discrepant declarations of progressive disease (PD) between LI and BICR in a clinical trial. Methods: We retrospectively analyzed imaging data from a RECIST 1.1-based, multi-sites, phase II clinical trial of 179 patients with adult small cell lung cancer, treated with Cabazitaxel compared to Topotecan. Any discrepancies in the determination of PD between LI and BICR readers were reviewed by a third-party adjudicator. For each imaging time point and reader, we recorded the selected target lesions, non-target lesions, and new lesions. Odds ratios were calculated to measure the association between discrepant declarations of PD and the differences in reviewed imaging scans (e.g. same imaging modality but with different reconstruction parameters) and selected lesions. Reasons for discrepancies were analyzed. Results: The average number of target lesions found by LI and BICR was respectively 2.9 and 3.4 per patient (p < 0.05), 18.4% of these target lesions were actually non-measurable. LI and BICR performed their evaluations based on different baseline imaging scans for 59% of the patients, they selected at least one different target lesion in 85% of patients. A total of 36.7% of patients required adjudication. Reasons of adjudication included differences in 1) reporting new lesions (53.7%), 2) the measured change of the tumor burden (18.5%), and 3) the progression of non-target lesions (11.2%). The rate of discrepancy was not associated with the selection of non-measurable target lesions or with the readers' assessment of different images. Paradoxically, more discrepancies occurred when LI and BICR selected exactly the same target lesions at baseline compared to when readers selected not exactly the same lesions. Conclusions: For a large proportion of evaluations, LI and BICR did not select the same imaging scans and target lesions but with a limited impact on the rate of discrepancy. The majority of discrepancies were explained by the difference in detecting new lesions. Trial Registration: ARD12166 (https://clinicaltrials.gov/ct2/show/NCT01500720).

Research paper thumbnail of Dietary Fat Intake During Adolescence and Breast Density Among Young Women

Cancer Epidemiology Biomarkers & Prevention, 2016

Background: Lack of association between fat intake and breast cancer risk in cohort studies might... more Background: Lack of association between fat intake and breast cancer risk in cohort studies might be attributed to the disregard of temporal effects during adolescence when breasts develop and are particularly sensitive to stimuli. We prospectively examined associations between adolescent fat intakes and breast density. Method: Among 177 women who participated in the Dietary Intervention Study in Children, dietary intakes at ages 10-18 years were assessed on five occasions by 24-hour recalls and averaged. We calculated geometric mean and 95% confidence intervals for MRI-measured breast density at ages 25-29 years across quartiles of fat intake using linear mixed-effect regression. Results: Comparing women in the extreme quartiles of adolescent fat intakes, percent dense breast volume (%DBV) was positively associated with saturated fat (mean ¼ 16.4% vs. 21.5%; P trend < 0.001). Conversely, %DBV was inversely associated with monounsaturated fat (25.0% vs. 15.8%; P trend < 0.001) and the ratio of polyunsaturated fat to saturated fat (P/S ratio; 19.1% vs. 14.3%; P trend < 0.001). When examining intake by pubertal stages, %DBV was inversely associated with intake of polyunsaturated fat (20.8% vs. 16.4%; P trend ¼ 0.04), long-chain omega-3 fat (17.8% vs. 15.8%; P trend < 0.001), and P/S ratio (22.5% vs. 16.1%; P trend < 0.001) before menarche, but not after. These associations observed with %DBV were consistently observed with absolute dense breast volume but not with absolute nondense breast volume. Conclusions: In our study, adolescent intakes of higher saturated fat and lower mono-and polyunsaturated fat are associated with higher breast density measured approximately 15 years later. Impact: The fat subtype composition in adolescent diet may be important in early breast cancer prevention. Cancer Epidemiol Biomarkers Prev; 25(6); 918-26. Ó2016 AACR.

Research paper thumbnail of A Bayesian segmentation approach to 3-D tomographic reconstruction from few radiographs

IEEE International Conference on Acoustics Speech and Signal Processing, 1993

A MAP (maximum a posteriori) 3-D reconstruction technique for estimating a solid object directly ... more A MAP (maximum a posteriori) 3-D reconstruction technique for estimating a solid object directly from sparse cone-beam data has been developed. In the present work, emphasis is placed on radiographic flaw detection in solid materials, which can be viewed as a segmentation of the object into a binary-valued reconstruction. Optimization is performed by iterated conditional modes, with deterministic convergence, but

Research paper thumbnail of Bayesian 3-D tomographic reconstruction from limited numbers of radiographs

IEEE Conference on Nuclear Science Symposium and Medical Imaging

ABSTRACT The authors consider 3-D tomographic reconstruction problems encountered using a small n... more ABSTRACT The authors consider 3-D tomographic reconstruction problems encountered using a small number of noisy radiographs. They present a Bayesian 3-D reconstruction method based on statistical models of the radiographic process and the generalized Markov random field (GGMRF) model for the 30D object. This model permits reconstruction of sharp density transitions in reconstructions. The authors present both the physical and probabilistic modeling issues and describe the techniques necessary to solve the optimization problems. They analytically present a technique for including Compton scattering in the reconstruction process and show the similarity in computation between the two cases

Research paper thumbnail of Abstract P4-01-04: MRI enhancement in stromal tissue surrounding breast tumors: Association with RFS following neoadjuvant chemotherapy

Cancer Research, 2012

Objective: Stromal tissue surrounding breast tumors can harbor abnormalities that predict increas... more Objective: Stromal tissue surrounding breast tumors can harbor abnormalities that predict increased risk of recurrence. The purpose of this study was to evaluate low-level contrast enhancement patterns in normal appearing breast stroma surrounding tumors using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). A secondary objective was to investigate whether enhancement patterns varied with distance from tumor and whether proximity-dependent enhancement was associated with recurrence-free survival following neoadjuvant chemotherapy (NACT). Materials and Methods: Sixty-three patients with locally-advanced breast cancer were imaged with DCE-MRI before (V1) and after one cycle (V2) of adriamycin-cytoxan (AC) therapy. Normal-appearing stromal tissue on MR images was defined as fibroglandular tissue outside of tumor regions. Fibroglandular tissue was segmented from pre-contrast T1-weighted images using a fuzzy C-means clustering method 1 . Tumor regions were identified using a percent enhancement threshold of 70% in the first post-contrast image (PE1). Distance from tumor (proximity) was defined for each stromal voxel as the minimum three-dimensional distance from any tumor voxel. Stromal enhancement was characterized by calculating mean PE and mean signal enhancement ratio (SER = PE1/PE2) in distance shells of 5 mm, from 0 to 40 mm outside of tumor tissue. Global PE and SER were calculated by averaging all stromal voxels from 5 to 40 mm from tumor. Proximity-dependent PE and SER were analyzed using a linear mixed effects model and Cox proportional hazards model for recurrence-free survival. Results: The mixed effects model displayed a decreasing radial trend in PE at both V1(estimated mean = −0.39 per mm, 95% CI (−0.50, −0.29), p Conclusions: These findings show that stromal tissue outside the primary tumor can be quantitatively characterized by DCE-MRI, and suggest that stromal enhancement measurements may be worth exploring as a potential predictor of recurrence/disease-free survival following NACT. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-01-04.

Research paper thumbnail of Repeatability of Quantitative MRI Measurements in Normal Breast Tissue

Translational Oncology, 2014

PURPOSE: To evaluate the variability and repeatability of repeated magnetic resonance imaging (MR... more PURPOSE: To evaluate the variability and repeatability of repeated magnetic resonance imaging (MRI) measurements in normal breast tissues between and within subjects. METHODS: Eighteen normal premenopausal subjects underwent two contrast-enhanced MRI scans within 72 hours or during the same menstrual phase in two consecutive months. A subset of nine women also completed diffusion-weighted imaging (DWI). Fibroglandular tissue (FGT) density and FGT enhancement were measured on the contrast-enhanced MRI. Apparent diffusion coefficient (ADC) values were computed from DWI. Between-and within-subject coefficients of variation (bCV and wCV, respectively) were assessed. Repeatability of all measurements was assessed by the coefficient of repeatability (CR) and Bland-Altman plots. RESULTS: The bCV of FGT density and FGT enhancement at visit 1 and visit 2 ranged from 47% to 63%. The wCV was 13% for FGT density, 22% for FGT enhancement, and 11% for ADC. The CRs of FGT density and FGT enhancement were 0.15 and 0.19, respectively, and for ADC, it was 6.1 × 10 −4 mm 2 /s. CONCLUSIONS: We present an estimate of the variability and repeatability of MR measurements in normal breasts. These estimates provide the basis for understanding the normal variation of healthy breast tissue in MRI and establishing thresholds for agreement between measurements.

Research paper thumbnail of Repeatability of Quantitative MRI Measurements in Normal Breast Tissue

Translational Oncology, 2014

PURPOSE: To evaluate the variability and repeatability of repeated magnetic resonance imaging (MR... more PURPOSE: To evaluate the variability and repeatability of repeated magnetic resonance imaging (MRI) measurements in normal breast tissues between and within subjects. METHODS: Eighteen normal premenopausal subjects underwent two contrast-enhanced MRI scans within 72 hours or during the same menstrual phase in two consecutive months. A subset of nine women also completed diffusion-weighted imaging (DWI). Fibroglandular tissue (FGT) density and FGT enhancement were measured on the contrast-enhanced MRI. Apparent diffusion coefficient (ADC) values were computed from DWI. Between-and within-subject coefficients of variation (bCV and wCV, respectively) were assessed. Repeatability of all measurements was assessed by the coefficient of repeatability (CR) and Bland-Altman plots. RESULTS: The bCV of FGT density and FGT enhancement at visit 1 and visit 2 ranged from 47% to 63%. The wCV was 13% for FGT density, 22% for FGT enhancement, and 11% for ADC. The CRs of FGT density and FGT enhancement were 0.15 and 0.19, respectively, and for ADC, it was 6.1 × 10 −4 mm 2 /s. CONCLUSIONS: We present an estimate of the variability and repeatability of MR measurements in normal breasts. These estimates provide the basis for understanding the normal variation of healthy breast tissue in MRI and establishing thresholds for agreement between measurements.

Research paper thumbnail of Diffuse optical spectroscopy and magnetic resonance imaging of breast tissue

Biomedical Topical Meeting, 2004

... Natasha Shah, Albert Cerussi and Bruce Tromberg Beckman Laser Institute, University of Califo... more ... Natasha Shah, Albert Cerussi and Bruce Tromberg Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Road, Irvine ... 2. BW Pogue, SP Poplack, TO McBride, WA Wells, KS Osterman, UL Osterberg and KD Paulsen, “Quantitative hemoglobin tomography ...

Research paper thumbnail of MRI Enhancement in Stromal Tissue Surrounding Breast Tumors: Association with Recurrence Free Survival following Neoadjuvant Chemotherapy

PLoS ONE, 2013

Rationale and Objectives: Normal-appearing stromal tissues surrounding breast tumors can harbor a... more Rationale and Objectives: Normal-appearing stromal tissues surrounding breast tumors can harbor abnormalities that lead to increased risk of local recurrence. The objective of this study was to develop a new imaging methodology to characterize the signal patterns of stromal tissue and to investigate their association with recurrence-free survival following neoadjuvant chemotherapy. Materials and Methods: Fifty patients with locally-advanced breast cancer were imaged with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) before (V1) and after one cycle (V2) of adriamycin-cytoxan therapy. Contrast enhancement in normal-appearing stroma around the tumor was characterized by the mean percent enhancement (PE) and mean signal enhancement ratio (SER) in distance bands of 5 mm from the tumor edge. Global PE and SER were calculated by averaging all stromal bands 5 to 40 mm from tumor. Proximity-dependent PE and SER were analyzed using a linear mixed effects model and Cox proportional hazards model for recurrence-free survival. Results: The mixed effects model displayed a decreasing radial trend in PE at both V1 and V2. An increasing trend was less pronounced in SER. Survival analysis showed that the hazard ratio estimates for each unit decrease in global SER was statistically significant at V1 [estimated hazard ratio = 0.058, 95% Wald CI (0.003, 1.01), likelihood ratio p = 0.03]; but was not so for V2. Conclusions: These findings show that stromal tissue outside the tumor can be quantitatively characterized by DCE-MRI, and suggest that stromal enhancement measurements may be further developed for use as a potential predictor of recurrence/disease-free survival following therapy.

Research paper thumbnail of Agreement of mammographic measures of volumetric breast density to MRI

PloS one, 2013

Clinical scores of mammographic breast density are highly subjective. Automated technologies for ... more Clinical scores of mammographic breast density are highly subjective. Automated technologies for mammography exist to quantify breast density objectively, but the technique that most accurately measures the quantity of breast fibroglandular tissue is not known. To compare the agreement of three automated mammographic techniques for measuring volumetric breast density with a quantitative volumetric MRI-based technique in a screening population. Women were selected from the UCSF Medical Center screening population that had received both a screening MRI and digital mammogram within one year of each other, had Breast Imaging Reporting and Data System (BI-RADS) assessments of normal or benign finding, and no history of breast cancer or surgery. Agreement was assessed of three mammographic techniques (Single-energy X-ray Absorptiometry [SXA], Quantra, and Volpara) with MRI for percent fibroglandular tissue volume, absolute fibroglandular tissue volume, and total breast volume. Among 99 wo...

Research paper thumbnail of Intake of dietary carbohydrates in early adulthood and adolescence and breast density among young women

Cancer causes & control : CCC, 2018

Carbohydrate intake increases postprandial insulin secretion and may affect breast density, a str... more Carbohydrate intake increases postprandial insulin secretion and may affect breast density, a strong risk factor for breast cancer, early in life. We examined associations of adolescent and early adulthood intakes of total carbohydrates, glycemic index/load, fiber, and simple sugars with breast density among 182 young women. Diet was assessed using three 24-h recalls at each of five Dietary Intervention Study in Children (DISC) clinic visits when participants were age 10-19 years and at the DISC06 Follow-Up Study clinic visit when participants were age 25-29 years. Associations between energy-adjusted carbohydrates and MRI-measured percent dense breast volume (%DBV) and absolute dense breast volume (ADBV) at 25-29 years were quantified using multivariable-adjusted mixed-effects linear models. Adolescent sucrose intakes and premenarcheal total carbohydrates intakes were modestly associated with higher %DBV (mean %DBV, 16.6 vs 23.5% for sucrose; and 17.2 vs 22.3% for premenarcheal tot...

Research paper thumbnail of Quantification of breast tissue index from MR data using fuzzy clustering

The 26th Annual International Conference of the IEEE Engineering in Medicine and Biology Society

The study objective was to develop a segmentation technique to quantify breast tissue and total b... more The study objective was to develop a segmentation technique to quantify breast tissue and total breast volume from magnetic resonance imaging (MRI) data to obtain a breast tissue index (BTI) related to breast density. Our goal is to quantify MR breast density to improve breast cancer risk assessment for certain high-risk populations for whom mammography is of limited usefulness due to high breast density. A semi-automatic 3D segmentation technique was implemented based on a fuzzy c-means technique (FCM) to segment fibroglandular tissue from fat in the breast images. After validation on a phantom, our FCM technique was first used to test the breast tissue measures reproducibility in two consecutive MR examinations of the same patients. The technique was then applied to measure the BTI on 10 high-risk patients. Results of BTI obtained with the semi-automated FCM method were compared with BTI results for the same patients using two other techniques, manual delineation and global threshold. BTI measures correlated well with mammographic densities (Pearson coefficients r = 0.78 using MR manual delineation, and r = 0.75 using MR FCM). The breast tissue index could therefore become a common measure for future studies of using noncontrast MRI data.

Research paper thumbnail of 2048: Breast Magnetic Resonance Imaging (MRI) Enhancement Beyond the Tumor Margin: Is There An Association With Treatment Response?

breast tissue (chest wall, pectoralis and lung). A dose of 38.5 Gy to the PTV_EVAL was planned in... more breast tissue (chest wall, pectoralis and lung). A dose of 38.5 Gy to the PTV_EVAL was planned in 10 fractions. A 5 cm jaw length and a pitch of 0.215 were used for planning. The doses to the ipsilateral breast, contralateral breast, heart, and both lungs were restricted during plan optimization to meet protocol guidelines. The treatment time and PTV_EVAL doses are reported. Results: Table 1 lists the average (range) of volumes that received the allowable dose according to protocol. For various structures, the RTOG volume limits are based on the percentage of the prescription dose (PD) that is allowed to a percentage volume. The second row lists the allowable volume limit. The third row lists the average and range of volumes that received the dose limit. In all cases, the maximum dose to the contralateral lung was Ͻ3% of the prescription dose. The average (range) treatment time was 10 (7-14) minutes. In 9 of the 10 cases, all PTV_EVAL and sensitive structure volume limits were acceptable (i.e. within 5% of specified value). In one right-sided case, the contralateral lung volume to 5% of the PD was 40% and the respective heart volume was 60%. This PTV_EVAL was located medially and dose limits to the contra lateral breast likely compromised the delivery. A solution with helical tomotherapy could be theoretically found with this particular situation, however, treatment times exceeded practical limits. Conclusions: In the large majority of patients, partial breast treatment helical tomotherapy plans were acceptable by RTOG Protocol 0413 guidelines. Although not the focus of the present study, megavoltage CT scanning prior to each fraction would also add the benefit of daily visualization and localization of the seroma, i.e. the tumor bed (Langen et al, IJROBP, 63S, p. S179, 2005), thus potentially allowing a decrease in treatment margins. Partial breast accelerated irradiation is feasible with helical tomotherapy delivery.

Research paper thumbnail of Study of Breast Tissue Composition Using Magnetic Resonance Imaging and Diffuse Optical Spectroscopy

Biomedical Optics, 2006

Abstract We combined Magnetic Resonance Imaging (MRI) and Diffuse Optical Spectroscopy (DOS) to s... more Abstract We combined Magnetic Resonance Imaging (MRI) and Diffuse Optical Spectroscopy (DOS) to study breast tissue composition in 20 healthy volunteers. A combination of MRI and DOS measures was found to be associated with breast density.

Research paper thumbnail of Characterization of breast lesions using the 3D FIESTA sequence and contrast-enhanced magnetic resonance imaging

Journal of Magnetic Resonance Imaging, 2007

Purpose: To determine whether combining 3D fast imaging employing steady-state acquisition (FIEST... more Purpose: To determine whether combining 3D fast imaging employing steady-state acquisition (FIESTA) and T1weighted contrast-enhanced (CE) sequences could help characterize lesions in 32 women with benign, in situ, or invasive breast lesions. Since FIESTA provides both T1 and T2 information on the same three-dimensional (3D) matrix as high-resolution T1-weighted dynamic data, we aimed to verify whether invasive lesions could be separated from in situ and/or benign lesions using quantitative FIESTA measures of tissue intensity and homogeneity. Material and Methods: With the use of CE-MRI data, regions of interest (ROIs) were manually delineated in enhancing lesions and on surrounding normal tissue. These ROIs were then applied to 3D FIESTA data. Quantitative measures between lesion and normal tissue were compared among the lesion groups. Results: On FIESTA most invasive cancer lesions were hypointense compared to surrounding normal tissue (mean lesion intensity was 89% of normal tissue intensity), whereas most ductal and benign lesions appeared hyperintense compared to surrounding normal tissue (lesions at 100.9% and 121.9% of normal tissue intensity, respectively). Measures obtained from resampled T2-weighted data showed no significant differences between the invasive and benign lesion groups. Conclusion: We detected significant differences between invasive and noninvasive lesions by quantifying intensity differences between the lesions and surrounding normal tissue on FIESTA.

Research paper thumbnail of Menstrual and reproductive characteristics and breast density in young women

Cancer Causes & Control, 2013

Purpose-Breast density is strongly related to breast cancer risk, but determinants of breast dens... more Purpose-Breast density is strongly related to breast cancer risk, but determinants of breast density in young women remain largely unknown.

Research paper thumbnail of Reconstruction 3D de defauts en radiographie industrielle

Certains matériels des centrales nucléaires soumis à de fortes contraintes sont contrôlés réguliè... more Certains matériels des centrales nucléaires soumis à de fortes contraintes sont contrôlés régulièrement par radiographies X ou gamma afin de vérifier leur intégrité. Or l'information donnée par un film radiographique ne permet pas de connaître l'orientation d'un défaut dans une pièce. L'étude consiste à reconstruire ces défauts dans l'espace 3D connaissant trois de leurs projections radiographiques. L'algorithme mis au point combine une reconstruction algébrique ART et une modélisation du volume 3D par des champs markoviens.

Research paper thumbnail of Reliability of the apparent diffusion coefficient assessment of cervical lymph nodes in phantoms and healthy volunteers

Poster: "ECR 2018 / C-0591 / Reliability of the apparent diffusion coefficient assessment of... more Poster: "ECR 2018 / C-0591 / Reliability of the apparent diffusion coefficient assessment of cervical lymph nodes in phantoms and healthy volunteers" by: "A. Iannessi1, H. Beaumont2, B. MOREAU1, C. Hoog1, C. Klifa2; 1Nice/FR, 2Valbonne/FR"

Research paper thumbnail of Pubertal timing and breast density in young women: a prospective cohort study

Breast Cancer Research, 2019

Background Earlier age at onset of pubertal events and longer intervals between them (tempo) have... more Background Earlier age at onset of pubertal events and longer intervals between them (tempo) have been associated with increased breast cancer risk. It is unknown whether the timing and tempo of puberty are associated with adult breast density, which could mediate the increased risk. Methods From 1988 to 1997, girls participating in the Dietary Intervention Study in Children (DISC) were clinically assessed annually between ages 8 and 17 years for Tanner stages of breast development (thelarche) and pubic hair (pubarche), and onset of menses (menarche) was self-reported. In 2006–2008, 182 participants then aged 25–29 years had their percent dense breast volume (%DBV) measured by magnetic resonance imaging. Multivariable, linear mixed-effects regression models adjusted for reproductive factors, demographics, and body size were used to evaluate associations of age and tempo of puberty events with %DBV. Results The mean (standard deviation) and range of %DBV were 27.6 (20.5) and 0.2–86.1...

Research paper thumbnail of Abstract 3262: Biomarkers of response to deslorelin in women at high risk of breast cancer

Prevention Research, 2018

Research paper thumbnail of Discrepancies of assessments in a RECIST 1.1 phase II clinical trial – association between adjudication rate and variability in images and tumors selection

Cancer Imaging, 2018

Background: In imaging-based clinical trials, it is common practice to perform double reads for e... more Background: In imaging-based clinical trials, it is common practice to perform double reads for each image, discrepant interpretations can result from these two different evaluations. In this study we analyzed discrepancies that occurred between local investigators (LI) and blinded independent central review (BICR) by comparing readerselected imaging scans and lesions. Our goal was to identify the causes of discrepant declarations of progressive disease (PD) between LI and BICR in a clinical trial. Methods: We retrospectively analyzed imaging data from a RECIST 1.1-based, multi-sites, phase II clinical trial of 179 patients with adult small cell lung cancer, treated with Cabazitaxel compared to Topotecan. Any discrepancies in the determination of PD between LI and BICR readers were reviewed by a third-party adjudicator. For each imaging time point and reader, we recorded the selected target lesions, non-target lesions, and new lesions. Odds ratios were calculated to measure the association between discrepant declarations of PD and the differences in reviewed imaging scans (e.g. same imaging modality but with different reconstruction parameters) and selected lesions. Reasons for discrepancies were analyzed. Results: The average number of target lesions found by LI and BICR was respectively 2.9 and 3.4 per patient (p < 0.05), 18.4% of these target lesions were actually non-measurable. LI and BICR performed their evaluations based on different baseline imaging scans for 59% of the patients, they selected at least one different target lesion in 85% of patients. A total of 36.7% of patients required adjudication. Reasons of adjudication included differences in 1) reporting new lesions (53.7%), 2) the measured change of the tumor burden (18.5%), and 3) the progression of non-target lesions (11.2%). The rate of discrepancy was not associated with the selection of non-measurable target lesions or with the readers' assessment of different images. Paradoxically, more discrepancies occurred when LI and BICR selected exactly the same target lesions at baseline compared to when readers selected not exactly the same lesions. Conclusions: For a large proportion of evaluations, LI and BICR did not select the same imaging scans and target lesions but with a limited impact on the rate of discrepancy. The majority of discrepancies were explained by the difference in detecting new lesions. Trial Registration: ARD12166 (https://clinicaltrials.gov/ct2/show/NCT01500720).

Research paper thumbnail of Dietary Fat Intake During Adolescence and Breast Density Among Young Women

Cancer Epidemiology Biomarkers & Prevention, 2016

Background: Lack of association between fat intake and breast cancer risk in cohort studies might... more Background: Lack of association between fat intake and breast cancer risk in cohort studies might be attributed to the disregard of temporal effects during adolescence when breasts develop and are particularly sensitive to stimuli. We prospectively examined associations between adolescent fat intakes and breast density. Method: Among 177 women who participated in the Dietary Intervention Study in Children, dietary intakes at ages 10-18 years were assessed on five occasions by 24-hour recalls and averaged. We calculated geometric mean and 95% confidence intervals for MRI-measured breast density at ages 25-29 years across quartiles of fat intake using linear mixed-effect regression. Results: Comparing women in the extreme quartiles of adolescent fat intakes, percent dense breast volume (%DBV) was positively associated with saturated fat (mean ¼ 16.4% vs. 21.5%; P trend < 0.001). Conversely, %DBV was inversely associated with monounsaturated fat (25.0% vs. 15.8%; P trend < 0.001) and the ratio of polyunsaturated fat to saturated fat (P/S ratio; 19.1% vs. 14.3%; P trend < 0.001). When examining intake by pubertal stages, %DBV was inversely associated with intake of polyunsaturated fat (20.8% vs. 16.4%; P trend ¼ 0.04), long-chain omega-3 fat (17.8% vs. 15.8%; P trend < 0.001), and P/S ratio (22.5% vs. 16.1%; P trend < 0.001) before menarche, but not after. These associations observed with %DBV were consistently observed with absolute dense breast volume but not with absolute nondense breast volume. Conclusions: In our study, adolescent intakes of higher saturated fat and lower mono-and polyunsaturated fat are associated with higher breast density measured approximately 15 years later. Impact: The fat subtype composition in adolescent diet may be important in early breast cancer prevention. Cancer Epidemiol Biomarkers Prev; 25(6); 918-26. Ó2016 AACR.

Research paper thumbnail of A Bayesian segmentation approach to 3-D tomographic reconstruction from few radiographs

IEEE International Conference on Acoustics Speech and Signal Processing, 1993

A MAP (maximum a posteriori) 3-D reconstruction technique for estimating a solid object directly ... more A MAP (maximum a posteriori) 3-D reconstruction technique for estimating a solid object directly from sparse cone-beam data has been developed. In the present work, emphasis is placed on radiographic flaw detection in solid materials, which can be viewed as a segmentation of the object into a binary-valued reconstruction. Optimization is performed by iterated conditional modes, with deterministic convergence, but

Research paper thumbnail of Bayesian 3-D tomographic reconstruction from limited numbers of radiographs

IEEE Conference on Nuclear Science Symposium and Medical Imaging

ABSTRACT The authors consider 3-D tomographic reconstruction problems encountered using a small n... more ABSTRACT The authors consider 3-D tomographic reconstruction problems encountered using a small number of noisy radiographs. They present a Bayesian 3-D reconstruction method based on statistical models of the radiographic process and the generalized Markov random field (GGMRF) model for the 30D object. This model permits reconstruction of sharp density transitions in reconstructions. The authors present both the physical and probabilistic modeling issues and describe the techniques necessary to solve the optimization problems. They analytically present a technique for including Compton scattering in the reconstruction process and show the similarity in computation between the two cases

Research paper thumbnail of Abstract P4-01-04: MRI enhancement in stromal tissue surrounding breast tumors: Association with RFS following neoadjuvant chemotherapy

Cancer Research, 2012

Objective: Stromal tissue surrounding breast tumors can harbor abnormalities that predict increas... more Objective: Stromal tissue surrounding breast tumors can harbor abnormalities that predict increased risk of recurrence. The purpose of this study was to evaluate low-level contrast enhancement patterns in normal appearing breast stroma surrounding tumors using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). A secondary objective was to investigate whether enhancement patterns varied with distance from tumor and whether proximity-dependent enhancement was associated with recurrence-free survival following neoadjuvant chemotherapy (NACT). Materials and Methods: Sixty-three patients with locally-advanced breast cancer were imaged with DCE-MRI before (V1) and after one cycle (V2) of adriamycin-cytoxan (AC) therapy. Normal-appearing stromal tissue on MR images was defined as fibroglandular tissue outside of tumor regions. Fibroglandular tissue was segmented from pre-contrast T1-weighted images using a fuzzy C-means clustering method 1 . Tumor regions were identified using a percent enhancement threshold of 70% in the first post-contrast image (PE1). Distance from tumor (proximity) was defined for each stromal voxel as the minimum three-dimensional distance from any tumor voxel. Stromal enhancement was characterized by calculating mean PE and mean signal enhancement ratio (SER = PE1/PE2) in distance shells of 5 mm, from 0 to 40 mm outside of tumor tissue. Global PE and SER were calculated by averaging all stromal voxels from 5 to 40 mm from tumor. Proximity-dependent PE and SER were analyzed using a linear mixed effects model and Cox proportional hazards model for recurrence-free survival. Results: The mixed effects model displayed a decreasing radial trend in PE at both V1(estimated mean = −0.39 per mm, 95% CI (−0.50, −0.29), p Conclusions: These findings show that stromal tissue outside the primary tumor can be quantitatively characterized by DCE-MRI, and suggest that stromal enhancement measurements may be worth exploring as a potential predictor of recurrence/disease-free survival following NACT. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-01-04.

Research paper thumbnail of Repeatability of Quantitative MRI Measurements in Normal Breast Tissue

Translational Oncology, 2014

PURPOSE: To evaluate the variability and repeatability of repeated magnetic resonance imaging (MR... more PURPOSE: To evaluate the variability and repeatability of repeated magnetic resonance imaging (MRI) measurements in normal breast tissues between and within subjects. METHODS: Eighteen normal premenopausal subjects underwent two contrast-enhanced MRI scans within 72 hours or during the same menstrual phase in two consecutive months. A subset of nine women also completed diffusion-weighted imaging (DWI). Fibroglandular tissue (FGT) density and FGT enhancement were measured on the contrast-enhanced MRI. Apparent diffusion coefficient (ADC) values were computed from DWI. Between-and within-subject coefficients of variation (bCV and wCV, respectively) were assessed. Repeatability of all measurements was assessed by the coefficient of repeatability (CR) and Bland-Altman plots. RESULTS: The bCV of FGT density and FGT enhancement at visit 1 and visit 2 ranged from 47% to 63%. The wCV was 13% for FGT density, 22% for FGT enhancement, and 11% for ADC. The CRs of FGT density and FGT enhancement were 0.15 and 0.19, respectively, and for ADC, it was 6.1 × 10 −4 mm 2 /s. CONCLUSIONS: We present an estimate of the variability and repeatability of MR measurements in normal breasts. These estimates provide the basis for understanding the normal variation of healthy breast tissue in MRI and establishing thresholds for agreement between measurements.

Research paper thumbnail of Repeatability of Quantitative MRI Measurements in Normal Breast Tissue

Translational Oncology, 2014

PURPOSE: To evaluate the variability and repeatability of repeated magnetic resonance imaging (MR... more PURPOSE: To evaluate the variability and repeatability of repeated magnetic resonance imaging (MRI) measurements in normal breast tissues between and within subjects. METHODS: Eighteen normal premenopausal subjects underwent two contrast-enhanced MRI scans within 72 hours or during the same menstrual phase in two consecutive months. A subset of nine women also completed diffusion-weighted imaging (DWI). Fibroglandular tissue (FGT) density and FGT enhancement were measured on the contrast-enhanced MRI. Apparent diffusion coefficient (ADC) values were computed from DWI. Between-and within-subject coefficients of variation (bCV and wCV, respectively) were assessed. Repeatability of all measurements was assessed by the coefficient of repeatability (CR) and Bland-Altman plots. RESULTS: The bCV of FGT density and FGT enhancement at visit 1 and visit 2 ranged from 47% to 63%. The wCV was 13% for FGT density, 22% for FGT enhancement, and 11% for ADC. The CRs of FGT density and FGT enhancement were 0.15 and 0.19, respectively, and for ADC, it was 6.1 × 10 −4 mm 2 /s. CONCLUSIONS: We present an estimate of the variability and repeatability of MR measurements in normal breasts. These estimates provide the basis for understanding the normal variation of healthy breast tissue in MRI and establishing thresholds for agreement between measurements.

Research paper thumbnail of Diffuse optical spectroscopy and magnetic resonance imaging of breast tissue

Biomedical Topical Meeting, 2004

... Natasha Shah, Albert Cerussi and Bruce Tromberg Beckman Laser Institute, University of Califo... more ... Natasha Shah, Albert Cerussi and Bruce Tromberg Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Road, Irvine ... 2. BW Pogue, SP Poplack, TO McBride, WA Wells, KS Osterman, UL Osterberg and KD Paulsen, “Quantitative hemoglobin tomography ...

Research paper thumbnail of MRI Enhancement in Stromal Tissue Surrounding Breast Tumors: Association with Recurrence Free Survival following Neoadjuvant Chemotherapy

PLoS ONE, 2013

Rationale and Objectives: Normal-appearing stromal tissues surrounding breast tumors can harbor a... more Rationale and Objectives: Normal-appearing stromal tissues surrounding breast tumors can harbor abnormalities that lead to increased risk of local recurrence. The objective of this study was to develop a new imaging methodology to characterize the signal patterns of stromal tissue and to investigate their association with recurrence-free survival following neoadjuvant chemotherapy. Materials and Methods: Fifty patients with locally-advanced breast cancer were imaged with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) before (V1) and after one cycle (V2) of adriamycin-cytoxan therapy. Contrast enhancement in normal-appearing stroma around the tumor was characterized by the mean percent enhancement (PE) and mean signal enhancement ratio (SER) in distance bands of 5 mm from the tumor edge. Global PE and SER were calculated by averaging all stromal bands 5 to 40 mm from tumor. Proximity-dependent PE and SER were analyzed using a linear mixed effects model and Cox proportional hazards model for recurrence-free survival. Results: The mixed effects model displayed a decreasing radial trend in PE at both V1 and V2. An increasing trend was less pronounced in SER. Survival analysis showed that the hazard ratio estimates for each unit decrease in global SER was statistically significant at V1 [estimated hazard ratio = 0.058, 95% Wald CI (0.003, 1.01), likelihood ratio p = 0.03]; but was not so for V2. Conclusions: These findings show that stromal tissue outside the tumor can be quantitatively characterized by DCE-MRI, and suggest that stromal enhancement measurements may be further developed for use as a potential predictor of recurrence/disease-free survival following therapy.

Research paper thumbnail of Agreement of mammographic measures of volumetric breast density to MRI

PloS one, 2013

Clinical scores of mammographic breast density are highly subjective. Automated technologies for ... more Clinical scores of mammographic breast density are highly subjective. Automated technologies for mammography exist to quantify breast density objectively, but the technique that most accurately measures the quantity of breast fibroglandular tissue is not known. To compare the agreement of three automated mammographic techniques for measuring volumetric breast density with a quantitative volumetric MRI-based technique in a screening population. Women were selected from the UCSF Medical Center screening population that had received both a screening MRI and digital mammogram within one year of each other, had Breast Imaging Reporting and Data System (BI-RADS) assessments of normal or benign finding, and no history of breast cancer or surgery. Agreement was assessed of three mammographic techniques (Single-energy X-ray Absorptiometry [SXA], Quantra, and Volpara) with MRI for percent fibroglandular tissue volume, absolute fibroglandular tissue volume, and total breast volume. Among 99 wo...