- Diagnostic Radiology
Professor - University Medical Line, Radiology
Member, Stanford Cancer Institute
Board Certification: American Board of Radiology, Diagnostic Radiology (1993)
Residency: Yale New Haven Medical Center Radiology Residency (1993) CT
Internship: Steward Carney Hospital (1989) MA
Medical Education: Boston University School of Medicine (1988) MA
Multishot Diffusion-Weighted MRI of the Breasts in the Supine vs. Prone Position.
Journal of magnetic resonance imaging : JMRI
BACKGROUND: Diffusion-weighted imaging (DWI) may allow for breast cancer screening MRI without a contrast injection. Multishot methods improve prone DWI of the breasts but face different challenges in the supine position.PURPOSE: To establish a multishot DWI (msDWI) protocol for supine breast MRI and to evaluate the performance of supine vs. prone msDWI.STUDY TYPE: Prospective.POPULATION: Protocol optimization: 10 healthy women (ages 22-56), supine vs. prone: 24 healthy women (ages 22-62) and five women (ages 29-61) with breast tumors.FIELD STRENGTH/SEQUENCE: 3-T, protocol optimization msDWI: free-breathing (FB) 2-shots, FB 4-shots, respiratory-triggered (RT) 2-shots, RT 4-shots, supine vs. prone: RT 4-shot msDWI, T2-weighted fast-spin echo.ASSESSMENT: Protocol optimization and supine vs. prone: three observers performed an image quality assessment of sharpness, aliasing, distortion (vs. T2), perceived SNR, and overall image quality (scale of 1-5). Apparent diffusion coefficients (ADCs) in fibroglandular tissue (FGT) and breast tumors were measured.STATISTICAL TESTS: Effect of study variables on dichotomized ratings (4/5 vs. 1/2/3) and FGT ADCs were assessed with mixed-effects logistic regression. Interobserver agreement utilized Gwet's agreement coefficient (AC). Lesion ADCs were assessed by Bland-Altman analysis and concordance correlation (rhoc ). P value <0.05 was considered statistically significant.RESULTS: Protocol optimization: 4-shots significantly improved sharpness and distortion; RT significantly improved sharpness, aliasing, perceived SNR, and overall image quality. FGT ADCs were not significantly different between shots (P=0.812), FB vs. RT (P=0.591), or side (P=0.574). Supine vs. prone: supine images were rated significantly higher for sharpness, aliasing, and overall image quality. FGT ADCs were significantly higher supine; lesion ADCs were highly correlated (rhoc =0.92).DATA CONCLUSION: Based on image quality, supine msDWI outperformed prone msDWI. Lesion ADCs were highly correlated between the two positions, while FGT ADCs were higher in the supine position.EVIDENCE LEVEL: 2.TECHNICAL EFFICACY: Stage 1.
View details for DOI 10.1002/jmri.28582
View details for PubMedID 36583628
A comparison of the imaging appearance of breast cancer in African American women with non-Latina white women.
2022; 93: 75-82
PURPOSE: To assess differences in the mammographic and sonographic appearance of breast cancer in African American (AA) and Non-Latina White (NLW) women.METHODS: We identified AA and NLW women with biopsy proven ductal carcinoma in situ or invasive breast cancer between June 1, 2015 and May 31, 2018. Racial differences in Breast Imaging and Reporting Data System (BI-RADS) imaging features were analyzed by imaging cohorts, i.e. screen detected vs. clinical presentation, using logistic regression adjusted for histology and molecular subtypes.RESULTS: We analyzed 270 AA women with 278 cancers (166 screen detected, 112 clinical) and 586 NLW women with 599 cancers (397 screen detected, 202 clinical). Compared with NLW women, AA women had higher rates of non-dense breast composition (almost entirely fatty 12.0% vs. 4.6%, scattered fibroglandular 50.9% vs. 45.2%; overall P<0001) in both cohorts and were less likely to have screen detected architectural distortion, (odds ratio (OR)=0.38, 95% CI 0.18-0.80). AA women were less likely than NLW women to have screen detected irregular than oval/round masses (mammography: OR=0.36, 95% CI 0.19-0.68; sonography: OR=0.48, 95% CI 0.24-0.94), and more likely to present clinically with high density masses (OR=3.03, 95% CI 1.12-8.20) demonstrating posterior enhancement (OR=3.02, 95% CI 1.11-8.27).CONCLUSION: There are racial differences in the mammographic and sonographic appearance of breast cancer even after accounting for higher rates of triple negative breast cancer in AA women. Understanding these differences may provide breast imagers with a framework to approach breast cancer diagnosis in the AA population in clinical practice.
View details for DOI 10.1016/j.clinimag.2022.11.004
View details for PubMedID 36413877
Prospective assessment of adjunctive ultrasound-guided diffuse optical tomography in women undergoing breast biopsy: Impact on BI-RADS assessments.
European journal of radiology
2021; 145: 110029
PURPOSE: To assess the impact of adjunctive ultrasound guided diffuse optical tomography (US-guided DOT) on BI-RADS assessment in women undergoing US-guided breast biopsy.METHOD: This prospective study enrolled women referred for US-guided breast biopsy between 3/5/2019 and 3/19/2020. Participants underwent US-guided DOT immediately before biopsy. The US-guided DOT acquisition generated average maximum total hemoglobin (HbT) spatial maps and quantitative HbT values. Four radiologists blinded to histopathology assessed conventional imaging (CI) to assign a CI BI-RADS assessment and then integrated DOT information in assigning a CI&DOT BI-RADS assessment. HbT was compared between benign and malignant lesions using an ANOVA test and Tukey's test. Benign biopsies were tabulated, deeming BI-RADS≥4A as positive. Reader agreement was assessed.RESULTS: Among 61 included women (mean age 48years), biopsy demonstrated 15 (24.6%) malignant and 46 (75.4%) benign lesions. Mean HbT was 55.3±22.6M in benign lesions versus 85.4±15.6M in cancers (p<.001). HbT threshold of 78.5M achieved sensitivity 80% (12/15) and specificity 89% (41/46) for malignancy. Across readers and patients, 197 pairs of CI BI-RADS and CI&DOT BI-RADS assessments were assigned. Adjunctive US-guided DOT achieved a net decrease in 23.5% (31/132) of suspicious (CI BI-RADS≥4A) assessments of benign lesions (34 correct downgrades and 3 incorrect upgrades). 38.3% (31/81) of 4A assessments were appropriately downgraded. No cancer was downgraded to a non-actionable assessment. Interreader agreement analysis demonstrated kappa=0.48-0.53 for CI BI-RADS and kappa=0.28-0.44 for CI&DOT BI-RADS.CONCLUSIONS: Integration of US-guided DOT information achieved a 23.5% reduction in suspicious BI-RADS assessments for benign lesions. Larger studies are warranted, with attention to improved reader agreement.
View details for DOI 10.1016/j.ejrad.2021.110029
View details for PubMedID 34801874
Early Assessment Window for Predicting Breast Cancer Neoadjuvant Therapy using Biomarkers, Ultrasound, and Diffuse Optical Tomography.
Breast cancer research and treatment
PURPOSE: The purpose of the study was to assess the utility of tumor biomarkers, ultrasound (US) and US-guided diffuse optical tomography (DOT) in early prediction of breast cancer responseto neoadjuvant therapy (NAT).METHODS: This prospective HIPAA compliant study was approved by the institutional review board. Forty one patients were imaged with US and US-guided DOT prior to NAT, at completion of the first three treatment cycles, and prior to definitive surgery from February 2017 to January 2020. Miller-Payne grading was used to assess pathologic response. Receiver operating characteristic curves (ROCs) were derived from logistic regression using independent variables, including: tumor biomarkers, US maximum diameter, percentage reduction of the diameter (%US), pretreatment maximum total hemoglobin concentration (HbT) and percentage reduction in HbT (%HbT) at different treatment time points. Resulting ROCs were compared using area under the curve (AUC). Statistical significance was tested using two-sided two-sample student t-test with P<0.05 considered statistically significant. Logistic regression was used for ROC analysis.RESULTS: Thirty-eight patients (mean age=47, range 24-71years) successfully completed the study, including 15 HER2+of which 11 were ER+; 12 ER+or PR+/HER2-, and 11 triple negative. The combination of HER2 and ER biomarkers, %HbT at the end of cycle 1 (EOC1) and %US (EOC1) provided the best early prediction, AUC=0.941 (95% CI 0.869-1.0). Similarly an AUC of 0.910 (95% CI 0.810-1.0) with %US (EOC1) and %HbT (EOC1) can be achieved independent of HER2 and ER status. The most accurate prediction, AUC=0.974 (95% CI 0.933-1.0), was achieved with %US at EOC1 and %HbT (EOC3) independent of biomarker status.CONCLUSION: The combined use of tumor HER2 and ER status, US, and US-guided DOT may provide accurate prediction of NAT response as early as the completion of the first treatment cycle.CLINICAL TRIAL REGISTRATION NUMBER: NCT02891681. https://clinicaltrials.gov/ct2/show/NCT02891681 , Registration time: September 7, 2016.
View details for DOI 10.1007/s10549-021-06239-y
View details for PubMedID 33970392
The impact of adjunctive tomosynthesis on screening mammography outcomes in two widely diverse radiology practices.
The breast journal
To determine the effect of adjunctive digital breast tomosynthesis screening on dissimilar mammography practices. We compared the outcomes of breast cancer screening with digital mammography versus digital mammography combined with tomosynthesis in two independent breast imaging practices from June 1, 2015, to May 31, 2016. Institution one was a hospital-based academic practice of breast imaging specialists and institution two was a community-based practice with academic affiliation served by general radiologists. Screening mammography was linked to subsequent diagnostic imaging and pathology. Subject characteristics and performance metrics were compared via t test for continuous variables and the chi-square test for categorical variables. A two-sided z test was performed to test modality differences for assessment and pathology subtype. Of the 54 638 women, 54% (n = 29 295) were from institution one and 55% (n = 30 013) underwent digital mammography alone. Women undergoing mammography with tomosynthesis were older (60.8 years vs 56.9 years, P < .001) and had slightly less dense breast composition (P = .001). Performance metrics varied substantially between institutions. At both institutions the biopsy rate, positive predictive value of screening (PPV1 ), and invasive cancer detection rate increased significantly with adjunctive tomosynthesis. At institution one, the biopsy rate increased from 1.4% to 1.9%, the PPV1 from 6.0% to 8.2%, and the invasive cancer detection rate from 3.4 to 4.9/1000 women screened. At institution two, the respective increases were from 0.7% to 1.0%, 5.5% to 11.0%, and 2.3% to 4.1/1000. Tomosynthesis recalled asymmetry less and mass more and resulted in fewer BI-RADS 1 and 2 assessments than screening with mammography alone. Adjunctive tomosynthesis appears to have a consistent impact on breast cancer screening performance metrics despite marked variation in breast imaging practice. Combined tomosynthesis screening has a significantly higher PPV1 , leads to a greater number of biopsies, and detects more invasive cancer than screening with digital mammography.
View details for DOI 10.1111/tbj.14121
View details for PubMedID 33274490