Measuring the effectiveness of an integrated intervention package to improve the level of infection prevention and control: a multi-centre study in Bangladesh

BACKGROUND

Infection prevention and control (IPC) is a critical component of delivering safe, effective and high-quality healthcare services, and eliminating avoidable healthcare-associated infections (HAIs) in health facilities, predominantly in population-dense settings such as Bangladesh.

AIM

Our study aimed to assess the effect of an integrated intervention package in improving the IPC level of the health facilities in Bangladesh.

METHODS

We conducted a pre-post intervention study in six district hospitals (DHs) and 13 Upazila Health Complexes (UHCs) in the six districts of Bangladesh. Baseline and endline assessments were conducted between March and December 2021 using the adapted World Health Organization Infection Prevention and Control Assessment Framework (WHO-IPCAF) tool. The IPCAF score, ranging from 0-800, was calculated by adding the scores of eight components, and the IPC promotion and practice level was categorized as Inadequate (0-200), Basic (201-400), Intermediate (401-600) and Advanced (601-800). The integrated intervention package including IPC committee formation, healthcare provider training, logistics provision, necessary guidelines distribution, triage/flu corners establishment, and infrastructure development was implemented in all facilities.

RESULTS

The average IPCAF score across all the facilities showed a significant increase from 16% (95% CI: 11.5-20.65%) to 54% (95% CI: 51.4-57.1%). Overall, the IPCAF score increased by 34 percentage points (P<0.001) in DHs and 40 percentage points (P<0.001) in UHCs. Following the intervention, 12 (three DHs, nine UHCs) of 19 facilities progressed from inadequate to intermediate, and another three DHs upgraded from basic to intermediate in terms of IPC level.

CONCLUSION

The integrated intervention package improved IPCAF score in all facilities.

International Interobserver Variability of Breast Density Assessment

PURPOSE

The aim of this study was to determine variability in visually assessed mammographic breast density categorization among radiologists practicing in Indonesia, the Netherlands, South Africa, and the United States.

METHODS

Two hundred consecutive 2-D full-field digital screening mammograms obtained from September to December 2017 were selected and retrospectively reviewed from four global locations, for a total of 800 mammograms. Three breast radiologists in each location (team) provided consensus density assessments of all 800 mammograms using BI-RADS® density categorization. Interreader agreement was compared using Gwet's AC2 with quadratic weighting across all four density categories and Gwet's AC1 for binary comparison of combined not dense versus dense categories. Variability of distribution among teams was calculated using the Stuart-Maxwell test of marginal homogeneity across all four categories and using the McNemar test for not dense versus dense categories. To compare readers from a particular country on their own 200 mammograms versus the other three teams, density distribution was calculated using conditional logistic regression.

RESULTS

For all 800 mammograms, interreader weighted agreement for distribution among four density categories was 0.86 (Gwet's AC2 with quadratic weighting; 95% confidence interval, 0.85-0.88), and for not dense versus dense categories, it was 0.66 (Gwet's AC1; 95% confidence interval, 0.63-0.70). Density distribution across four density categories was significantly different when teams were compared with one another and one team versus the other three teams combined (P < .001). Overall, all readers placed the largest number of mammograms in the scattered and heterogeneous categories.

CONCLUSIONS

Although reader teams from four different global locations had almost perfect interreader agreement in BI-RADS density categorization, variability in density distribution across four categories remained statistically significant.

1362 ANTICHOLINERGIC PRESCRIBING HABITS AND ITS ASSOCIATIONS IN A COMMUNITY POPULATION OF PEOPLE LIVING WITH DEMENTIA

Introduction

Many commonly prescribed medications have inadvertent anticholinergic effects. People with Dementia (PwD) are more vulnerable to these effects and at risk of adverse outcomes, the risk being higher with a greater degree of anticholinergic exposure. We investigated prescribing patterns and Anticholinergic burden (ACB) in a cohort of community-dwelling older adults with dementia and aimed to explore the effect of ACB on cognition, mood, and quality of life(QoL).

Method

The medication and demographic information for 87 (39 female) community-dwelling PwD were obtained from Electronic Care Summaries. We used the German Anticholinergic Burden Scale (GABS) to measure ACB. Additionally, we investigated associations between ACB and cognitive (ADAS-Cog), functional (BADL) and QoL (DemQoL) assessments.

Results

28.7% of participants had a clinically significant score (ACB&gt; 2). The most commonly prescribed medications with ACB were Lansoprazole(18.3%), Mirtazapine(12.6%) and Codeine(12.6%). ACB was higher in males and negatively correlated with age, r(87)=-.21,p=.03. There was no association between ACB and cognition, QoL, functional independence, and neuropsychiatric symptoms. Over six months, PLWD with no ACB had a greater negative change in neuropsychiatric symptoms[t(18)=2.27,p=.04] and functional independence[t(23)=-3.8,p=.001], indicating greater dependence and worsening neuropsychiatric symptoms.

Conclusion

A third of PLWD in the community had clinically significant ACB. No ACB was associated with worsening neuropsychiatric symptoms and functional dependence over a six-month period. Community prescribers should consider regular medication reviews with PLWD and carers to ensure medications are prescribed safely and appropriately.

Clinical Diagnoses and Outcomes After Diagnostic Breast Ultrasound by Nurses and General Practitioner Physicians in Rural Rwanda

PURPOSE

To scale up early detection of breast cancer in low- and middle-income countries, research is needed to inform the role of diagnostic breast ultrasound performed by nonradiologists in resource-constrained settings. The authors examined 2-year clinical follow-up and outcomes among women who underwent diagnostic breast ultrasound performed by nonradiologist clinicians participating in a breast ultrasound training and mentorship program at a rural Rwandan hospital.

METHODS

Imaging findings, management plans, and pathologic results were prospectively collected during the training using a standardized form. Data on follow-up and outcomes for patients receiving breast ultrasound between January 2016 and March 2017 were retrospectively collected through medical record review.

RESULTS

Two hundred twenty-nine breast palpable findings (199 patients) met the study's eligibility criteria. Of 104 lesions initially biopsied, 38 were malignant on initial biopsy; 3 lesions were identified as malignant on repeat biopsy. All 34 patients ultimately diagnosed with cancer received initial recommendations for either biopsy or aspiration by trainees. The positive predictive value of trainee biopsy recommendation was 34.8% (95% confidence interval, 24.8%-45.0%). The sensitivity of trainees' biopsy recommendation for identifying malignant lesions was 92.7% (95% confidence interval, 84.2%-100%). Of 46 patients who did not receive biopsy and were told to return for clinical or imaging follow-up, 37.0% did not return.

CONCLUSIONS

Trained nonradiologist clinicians in Rwanda successfully identified suspicious breast lesions on diagnostic breast ultrasound. Loss to follow-up was common among patients instructed to return for surveillance, so lower biopsy thresholds, decentralized surveillance, or patient navigation should be considered for patients with low- or intermediate-suspicion lesions.

Downstream Mammary and Extramammary Cascade Services and Spending Following Screening Breast Magnetic Resonance Imaging vs Mammography Among Commercially Insured Women

IMPORTANCE

Increasing use of screening breast magnetic resonance imaging (MRI), including among women at low or average risk of breast cancer, raises concerns about resulting mammary and extramammary cascades (downstream services and new diagnoses) of uncertain value.

OBJECTIVE

To estimate rates of cascade events (ie, laboratory tests, imaging tests, procedures, visits, hospitalizations, and new diagnoses) and associated spending following screening breast MRI vs mammography among commercially insured US women.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used 2016 to 2018 data from the MarketScan research database (IBM Corporation), which includes claims and administrative data from large US employers and commercial payers. Participants included commercially insured women aged 40 to 64 years without prior breast cancer who received an index bilateral screening breast MRI or mammogram between January 1, 2017, and June 30, 2018. We used propensity scores based on sociodemographic, clinical, and utilization variables to match MRI recipients to mammogram recipients in each month of index service use. Data were analyzed from October 8, 2020, to October 28, 2021.

EXPOSURES

Breast MRI vs mammography.

MAIN OUTCOMES AND MEASURES

Mammary and extramammary cascade event rates and associated total and patient out-of-pocket spending in the 6 months following the index test.

RESULTS

In this study, 9208 women receiving breast MRI were matched with 9208 women receiving mammography (mean [SD] age, 51.4 [6.7] years). Compared with mammogram recipients, breast MRI recipients had 39.0 additional mammary cascade events per 100 women (95% CI, 33.7-44.2), including 5.0 additional imaging tests (95% CI, 3.8-6.2), 17.3 additional procedures (95% CI, 15.5-19.0), 13.0 additional visits (95% CI, 9.4-17.2), 0.34 additional hospitalizations (95% CI, 0.18-0.50), and 3.0 additional new diagnoses (95% CI, 2.5-3.6). For extramammary cascades, breast MRI recipients had 19.6 additional events per 100 women (95% CI, 8.6-30.7) including 15.8 additional visits (95% CI, 10.2-21.4) and no statistically significant differences in other events. Breast MRI recipients had higher total spending for mammary events ($564 more per woman; 95% CI, $532-$596), extramammary events ($42 more per woman; 95% CI, $16-$69), and overall ($1404 more per woman; 95% CI, $1172-$1636). They also had higher overall out-of-pocket spending ($31 more per woman; 95% CI, $6-$55).

CONCLUSIONS AND RELEVANCE

In this cohort study of commercially insured women, breast MRI was associated with more mammary and extramammary cascade events and spending relative to mammography. These findings can inform cost-benefit assessments and coverage policies to ensure breast MRI is reserved for patients for whom benefits outweigh harms.

Persistent inter-observer variability of breast density assessment using BI-RADS® 5th edition guidelines

OBJECTIVES

Due to most states' legislation, mammographic density categorization has potentially far-reaching implications, but remains subjective based on BIRADS® guidelines. We aimed to determine 1) effect of BI-RADS® 5th edition (5th-ed) vs 4th-edition (4th-ed) guidelines on reader agreement regarding density assessment; 2) 5th-ed vs 4th-ed density distribution, and visual vs quantitative assessment agreement; 3) agreement between experienced vs less experienced readers.

METHODS

In a retrospective review, six breast imaging radiologists (BIR) (23-30 years' experience) visually assessed density of 200 screening mammograms performed September 2012-January 2013 using 5th-ed guidelines. Results were compared to 2016 data of the same readers evaluating the same mammograms using 4th-ed guidelines after a training module. 5th-ed density categorization by seven junior BIR (1-5 years' experience) was compared to eight experienced BIR. Nelson et al.'s kappas (κ_m, κ_w), Fleiss' κ_F, and Cohen's κ were calculated. Quantitative density using Volpara was compared with reader assessments.

RESULTS

Inter-reader weighted agreement using 5th-ed is moderately strong, 0.73 (κ_w, s.e. = 0.01), similar to 4th-ed, 0.71 (κ_w, s.e. = 0.03). Intra-reader Cohen's κ is 0.23-0.34, similar to 4th-ed. Binary not-dense vs dense categorization, using 5th-ed results in higher dense categorization vs 4th-ed (p < 0.001). 5th-ed density distribution results in higher numbers in categories B/C vs 4th-ed (p < 0.001). Distribution for 5th-ed does not differ based on reader experience (p = 0.09). Reader vs quantitative weighted agreement is similar (5th-ed, Cohen's κ = 0.76-0.85; 4th-ed, Cohen's κ = 0.68-0.83).

CONCLUSION

There is persistent subjectivity of visually assessed mammographic density using 5th-ed guidelines; experience does not correlate with better inter-reader agreement.

How Often Does Retrieval of a Clipped Lymph Node Change Adjuvant Therapy Recommendations? A Prospective, Consecutive, Patient Cohort Study

BACKGROUND

Prior studies examining sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NAC) for cN1 patients have demonstrated that 20% of biopsied, clipped lymph nodes (cLNs) are nonsentinel lymph nodes (non-SLNs). Our goal was to determine how often the cLN was a non-SLN among both cN0 and cN1 patients and how often cLN pathology impacted management.

METHODS

Overall, 238 patients treated with NAC and surgery January 2019 to June 2020 were prospectively examined. Patients underwent routine axillary ultrasound, biopsy of suspicious nodes, and clip placement. Radioactive iodine-125 seed localization of the cLN was performed in cN1 patients only. Isolated tumor cells (ITCs) were considered node positive (ypN+) for both cN0 and cN1 cohorts. Chart review was performed to determine if cLNs were non-SLN and their ypN status.

RESULTS

Of 118 cN0 patients, 115 of 118 (97%) underwent successful SLNB, 33 of whom had a cLN present; 21 of 33 (64%) cLNs were non-SLNs. Overall, 9 of 118 (8%) were ypN+; no cLN was ypN+ without additional +SLNs. Of 120 cN1 patients, 104 of 120 (87%) converted to cN0, 98 of 104 (94%) of which had attempted SLNB, and 95 of 98 (97%) successfully mapped. The cLN was a non-SLN in 18 of 95 (19%). Overall, 58 of 104 (56%) cN1 patients were ypN+. One patient had a positive cLN in the absence of +SLNs. This patient underwent axillary lymph node dissection (ALND); adjuvant treatment recommendations were unchanged.

CONCLUSIONS

The cLN was a non-SLN in 19% of cN1 patients. cLN pathology did not impact adjuvant therapy recommendations, calling into question the utility of routinely clipping biopsied lymph nodes.

Skin Nodules as a First Presentation of Synchronous Bilateral Invasive Lobular Breast Carcinoma: A Case Report

The most common cause of skin metastases in adult women is primary breast carcinoma, which comprises about 70% of cases [1]. Skin metastases have non-specific clinical appearances, making it challenging to differentiate them from other benign conditions [1]. We present a case of a 52-year-old female with type II diabetes and a three-month history of refractory skin lesions who did not respond to anti-inflammatory treatment. The patient subsequently complained of a right breast lump, evaluation of which led to the diagnosis of bilateral synchronous invasive lobular carcinoma.

Understanding the future research needs in Postural Orthostatic Tachycardia Syndrome (POTS): Evidence mapping the POTS adult literature

POTS is under diagnosed with an estimated prevalence of 0.2%. North American and Australian researchers, as well as patient groups have called for more research into POTS. However, there has been no comprehensive appraisal of the current POTS evidence base.

AIM

To map the POTS evidence base.

METHODS

Two reviewers systematically searched 12 databases until July 1st 2019 using the search term "Postural Tachycardia Syndrome" (n = 7280) and categorised the literature. Inclusion criteria included all adult published literature with no language restrictions. 779 papers are analysed and mapped.

RESULTS

Seven themes were identified: symptomology and quality of life 16.8% (n = 132), biomedical topics 16.5% (n = 130), co-morbidities 10.3% (n = 81), non-pharmacological management 9.8% (n = 77), aetiologies 6.9% (n = 53), pharmacological management 6.7% (n = 53), and clinical management 6.6% (n = 52). There 45 subthemes. Quality appraisal of the research studies (n = 233) evaluated design, sample size, outcome measures, data analysis and research biases. 74.8% (n = 175) were observational designs and 25.2% (n = 59) were experimental designs (16 using a randomised controlled design, 11 of which had a sample size greater than 21). 47.4% (n = 111) of studies only measured duration of effect for <1 day. 11.5% (n = 27) of studies reported outcomes using an unvalidated subjective measurement tool.

CONCLUSION

The volume of adult POTS literature is small and the validity and reliability of the research lacks rigour. The evidence map methodology provides POTS researchers with a benchmark for research thus far. This paper adds an in-depth research appraisal to the broad calls for action, highlighting the pressing need for multicentre, good quality research in POTS, to support guidelines and consensus development in the future.

Abstract PD4-06: How often does retrieval of a clipped lymph node change adjuvant therapy recommendations? A prospective consecutive patient cohort

Objectives and Rationale: For breast cancer patients receiving neoadjuvant chemotherapy (NAC) and undergoing pre-NAC axillary lymph node biopsy, NCCN guidelines recommend biopsy marker (clip) placement. This recommendation is based on reports that retrieval of the clipped node after NAC minimizes the false negative rate of sentinel lymph node biopsy (SLNB). Prior studies examining this practice in cN1 patients have reported that the clipped node is a non-SLN 20% of the time. There is limited data regarding if the clipped node needs to be retrieved among cN0 patients, and how often the post-NAC pathologic status of the clipped node has potential to change adjuvant therapy decisions. Here we aim to determine: 1) how often the clipped node is a non-SLN among both cN0 and cN1 patients, and 2) how often the retrieved, clipped node is a non-SLN and is the only positive node after NAC, potentially impacting adjuvant treatment recommendations.

Methods: A consecutive cohort of 147 patients treated with NAC and surgery at our institution between January 2019-May 2020 was prospectively examined. Prior to NAC, all patients underwent routine axillary ultrasound (AxUS). For those with an abnormal appearing node, biopsy was performed of the most suspicious lymph node and a clip was placed. All cN0 patients underwent SLNB without localization of the clipped node. Patients who converted from cN1 to cN0 underwent radioactive seed localization of the clipped node and SLNB with dual tracers (radioactive tracer and blue dye). All lymph nodes were analyzed by IHC. Any residual disease, including ITCs, was considered pathologic node positive (ypN+). Patients with DCIS/unknown breast tumor histology (N = 3), those without AxUS (N = 9), those treated with neoadjuvant endocrine therapy (N = 9) and cN1 patients without a clip (N = 2) were excluded. Descriptive analyses were performed to examine the rate of ypN+ disease among cN0 and cN1 patients, and how often the clipped node was a non-SLN containing residual disease. In the cN0 population, if the clipped node was not obtained during SLNB it was considered a non-SLN.

Results: Of 124 patients meeting study criteria, 61 were cN0 and 63 cN1. Among cN0 patients, 21 (34%) had suspicious lymph nodes on AxUS which were biopsied (negative) and clipped. All cN0 patients underwent successful SLNB, with a median of 2 SLNs removed (range 1-10). Of these, 5 (8%) were ypN+. Of the 21 patients with clipped nodes, 14 (67%) of the clipped nodes were non-SLN. If &lt;3 SLNs were sampled, the clipped non-SLN rate was 82% (9/11). If ≥3 were sampled, the clipped non-SLN rate was 50% (5/10). Among patients with clipped nodes and ypN+ disease, there were no cases in which the clipped node was the only positive node.

Among 63 cN1 patients with clipped nodes, 55 (87%) converted to cN0 and underwent SLNB. SLNB was successful in 52/55 (95%) and a median of 3 SLNs were removed (range 1-8). Overall, 28/55 (51%) were ypN+. Of the 52 with successful SLNB, 15 (29%) of the clipped nodes were non-SLN. If &lt;3 SLNs were sampled, the clipped non-SLN rate was 46% (6/13). If ≥3 were sampled, the clipped non-SLN rate was 23% (9/39). In one of 52 (2%) patients, the clipped non-SLN was the only positive node.

Conclusions: In this prospective study, among cN0 patients with negative pre-NAC lymph node biopsies, the clipped node was frequently a non-SLN and pathologic status of the clipped node alone did not impact management. Among cN1 patients suitable for SLNB after NAC, although the clipped node was a non-SLN 29% of the time, it was the only positive node in only one patient. The finding that the post-NAC pathologic status of the clipped lymph node alone potentially changed adjuvant treatment recommendations in only 2% (1/52) of patients warrants further investigation.

Citation Format: Anna Weiss, Claire King, Samantha Grossmith, Leah Portnow, Sughra Raza, Faina Nakhlis, Laura Dominici, Elizabeth A. Mittendorf, Tari A. King. How often does retrieval of a clipped lymph node change adjuvant therapy recommendations? A prospective consecutive patient cohort [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD4-06.

Lesion conspicuity on synthetic screening mammography compared to full field digital screening mammography

OBJECTIVE

To compare lesion conspicuity on synthetic screening mammography (SM) plus digital breast tomosynthesis (DBT) versus full field digital mammography (FFDM) plus DBT.

MATERIALS AND METHODS

Seven breast imagers each prospectively evaluated 107-228 screening mammograms (FFDM, DBT, and SM; total 1206 examinations) over 12 weeks in sets of 10-50 consecutive examinations. Interpretation sessions alternated as follows: SM + DBT, then FFDM, or FFDM + DBT, then SM. Lesion conspicuity on SM versus FFDM (equal/better versus less) was assessed using proportions with 95% confidence intervals. DBT-only findings were excluded.

RESULTS

Overall 1082 of 1206 (89.7%) examinations were assessed BI-RADS 1/2, and 124 of 1206 (10.3%) assessed BI-RADS 0. There were 409 evaluated findings, including 134 masses, 119 calcifications, 72 asymmetries, 49 architectural distortion, and 35 focal asymmetries. SM conspicuity compared to FFDM conspicuity for lesions was rated 1) masses: 77 (57%) equal or more conspicuous, 57 (43%) less conspicuous; 2) asymmetries/focal asymmetries: 61 (57%) equal or more conspicuous, and 46 (43%) less conspicuous; 3) architectural distortion: 46 (94%) equal or more conspicuous, 3 (6%) less conspicuous; 4) calcifications: 115 (97%) equal or more conspicuous, 4 (3%) less conspicuous. SM had better conspicuity than FFDM for calcifications and architectural distortion and similar conspicuity for most masses and asymmetries.

CONCLUSION

Compared to FFDM, SM has better conspicuity for calcifications and architectural distortion and similar conspicuity for most masses and asymmetries.

Training Nonradiologist Clinicians in Diagnostic Breast Ultrasound in Rural Rwanda: Impact on Knowledge and Skills

OBJECTIVE

To assess the effectiveness of diagnostic breast ultrasound training provided for general practitioners and nurses in Rwanda via intensive in-person and subsequent online supervision and mentorship.

METHODS

Four breast radiologists from Brigham and Women's Hospital trained two general practitioner physicians and five nurses in Rwanda over 9 total weeks of in-person training and 20 months of remote mentorship using electronic image review with emailed feedback. Independently recorded assessments were compared to calculate the sensitivity and specificity of trainee assessments, with radiologist assessments as the gold standard. We compared performance in the first versus second half of the training.

RESULTS

Trainees' performance on written knowledge assessments improved after training (57.7% versus 98.1% correct, P = .03). Mean sensitivity of trainee-performed ultrasound for identifying a solid breast mass was 90.6% (SD 4.2%) in the first half of the training (period 1) and 94.0% (SD 6.7%) in period 2 (P = .32). Mean specificity was 94.7% (SD 5.4%) in period 1 and 100.0% (SD 0) in period 2 (P = .10). Mean sensitivity for identifying a medium- or high-suspicion solid mass increased from 79.2% (SD 11.0%) in period 1 to 96.3% (SD 6.4%) in period 2 (P = .03). Specificity was 84.4% (SD 15.0%) in period 1 and 96.7% (SD 5.8%) in period 2 (P = .31).

DISCUSSION

Nonradiologist clinicians (doctors and nurses) in a rural sub-Saharan African hospital built strong skills in diagnostic breast ultrasound over 23 months of combined in-person training and remote mentorship. The sensitivity of trainees' assessments in identifying masses concerning for malignancy improved after sustained mentorship. Assessment of impact on patient care and outcomes is ongoing.

A Randomized Cross-Over Trial Focused on Clinical Breast Exam Skill Acquisition Using High Fidelity versus Low Fidelity Simulation Models in Rwanda

OBJECTIVE

Breast cancer incidence is rising for women in low and middle income country (LMIC)s. Growing the health care workforce trained in clinical breast exam (CBE) is critical to mitigating breast cancer globally. We developed a CBE simulation training course and determined whether training on a low-fidelity (LF) simulation model results in similar skill acquisition as training on high-fidelity (HF) models in Rwanda.

DESIGN

A single-center randomized educational crossover trial was implemented. A preintervention baseline exam (exam 1), followed by a lecture series (exam 2), and training sessions with assigned simulation models was implemented (exam 3)-participants then crossed over to their unassigned model (exam 4). The primary outcome of this study determined mean difference in CBE exam scores between HF and LF groups. Secondary outcomes identified any provider level traits and changes in overall scores.

SETTING

The study was implemented at the University Teaching Hospital, Kigali (CHUK) in Rwanda, Africa from July 2014 to March 2015 PARTICIPANTS: Medical students, residents in surgery, obstetrics and gynecology, and internal medicine residents participated in a 1-day CBE simulation training course.

RESULTS

A total of 107 individuals were analyzed in each arm of the study. Mean difference in exam scores between HF and LF models in exam 1 to 4 was not significantly different (exam 1 0.08 standard error (SE) = 0.47, p = 0.42; exam 2 0.86, SE = 0.69, p = 0.16; exam 3 0.03, SE = 0.38, p = 0.66; exam 4 0.10 SE = 0.37, p = 0.29). Overall exam scores improved from pre- to post-intervention.

CONCLUSIONS

Mean difference in exams scores were not significantly different between participants trained with HF versus LF models. LF models can be utilized as cost effective teaching tools for CBE skill acquisition, in resource poor areas.

Methods of assessing categorical agreement between correlated screening tests in clinical studies

Advances in breast imaging and other screening tests have prompted studies to evaluate and compare the consistency between experts' ratings of existing with new screening tests. In clinical settings, medical experts make subjective assessments of screening test results such as mammograms. Consistency between experts' ratings is evaluated by measures of inter-rater agreement or association. However, conventional measures, such as Cohen's and Fleiss' kappas, are unable to be applied or may perform poorly when studies consist of many experts, unbalanced data, or dependencies between experts' ratings exist. Here we assess the performance of existing approaches including recently developed summary measures for assessing the agreement between experts' binary and ordinal ratings when patients undergo two screening procedures. Methods to assess consistency between repeated measurements by the same experts are also described. We present applications to three large-scale clinical screening studies. Properties of these agreement measures are illustrated via simulation studies. Generally, a model-based approach provides several advantages over alternative methods including the ability to flexibly incorporate various measurement scales (i.e. binary or ordinal), large numbers of experts and patients, sparse data, and robustness to prevalence of underlying disease.

Epigenetic Reprogramming of Cancer-Associated Fibroblasts Deregulates Glucose Metabolism and Facilitates Progression of Breast Cancer

The mechanistic contributions of cancer-associated fibroblasts (CAFs) in breast cancer progression remain to be fully understood. While altered glucose metabolism in CAFs could fuel cancer cells, how such metabolic reprogramming emerges and is sustained needs further investigation. Studying fibroblasts isolated from patients with benign breast tissues and breast cancer, in conjunction with multiple animal models, we demonstrate that CAFs exhibit a metabolic shift toward lactate and pyruvate production and fuel biosynthetic pathways of cancer cells. The depletion or suppression of the lactate production of CAFs alter the tumor metabolic profile and impede tumor growth. The glycolytic phenotype of the CAFs is in part sustained through epigenetic reprogramming of HIF-1α and glycolytic enzymes. Hypoxia induces epigenetic reprogramming of normal fibroblasts, resulting in a pro-glycolytic, CAF-like transcriptome. Our findings suggest that the glucose metabolism of CAFs evolves during tumor progression, and their breast cancer-promoting phenotype is partly mediated by oxygen-dependent epigenetic modifications.

Generation of low-symmetry perovskite structures for ab initio computation

Ion displacements are the fundamental cause of ferroelectricity in perovskites. By properly shifting ions, ab initio computations have been extensively used to investigate the properties of perovskites in various structural phases. In addition to the relatively simple ion displacements, perovskites have another type of structural distortion known as antiferrodistortion or oxygen octahedron tilting. The interplay between these two types of distortions have generated abundant structural phases that can be tedious to prepare for ab initio computation, especially for large supercells. Here, we design and implement a computer program to facilitate the generation of distorted perovskite structures, which can be readily used for ab initio computation to gain further insight into the perovskite of a given structural phase.

A Randomized Cross-Over Trial Focused on Breast Core Needle Biopsy Skill Acquisition and Safety Using High Fidelity Versus Low Fidelity Simulation Models in Rwanda

OBJECTIVE

Breast cancer is the most common cancer diagnosed in low and middle-income countries. Growing the number of health care personnel trained in diagnostic procedures like breast core needle biopsy (BCNB) is critical. We developed a BCNB simulation-training course that evaluated skill acquisition, confidence, and safety, comparing low-cost low fidelity (LF) models to expensive high fidelity (HF) models.

DESIGN

A single-center randomized education crossover trial was implemented. Participants were randomized to HF or LF groups. A preintervention baseline exam followed by lectures and training sessions with a HF or LF model was implemented. A postintervention simulation exam was conducted, and participants crossed over to the other simulation model.

SETTING

The study was implemented at the University Teaching Hospital, Kigali (CHUK) in Rwanda, Africa from October 2014 to March 2015.

PARTICIPANTS

Residents training in surgery or obstetrics and gynecology participated in a 1-day BCNB training course.

RESULTS

A total of 36 residents were analyzed, 19 in the HF arm and 17 in the LF arm. Mean difference in exam scores for HF and LF groups in the baseline exam (exam 1) (0.067, p = 0.94, standard error [SE] of 1.57) postintervention exam (exam 2) (1.85, SE 1.46, p = 0.33), and the crossover exam (exam 3) (4.39, SE = 1.90, p = 0.11) were not significantly different between HF and LF. Overall exam scores improved from pre- to postintervention.

CONCLUSIONS

Our results indicate that mean difference in exams scores were not significantly different between residents trained with HF versus LF models. In resources poor areas-LF models can be utilized as effective teaching tools for skill acquisition for diagnostic surgical procedures.

Abstract OT3-15-02: A randomized, double-blind, placebo-controlled study of 4-hydroxytamoxifen topical gel in women with mammographically dense breasts

Background: Tamoxifen uptake for risk reduction has remained low due to concerns about toxicity despite the efficacy and effectiveness data available. Studies of tamoxifen in the adjuvant and preventive setting have demonstrated that a decline in mammographic density (MD) of approximately 10% is consistently associated with better outcomes. Additionally, MD is one of the strongest independent predictors of breast cancer risk, apart from older age and BRCA1/2 mutation, among women. 4-hydroxytamoxifen topical gel (4-OHT) is a transdermal agent, shown in preliminary studies to be well-tolerated with similar decreases in Ki-67 to oral tamoxifen in presurgical DCIS studies and significant drug concentration in breast parenchyma but very low levels in the systemic circulation. This study examines changes in MD, a potential surrogate biomarker of prevention activity, as the primary endpoint for this one-year early-phase prevention trial using 4-OHT gel in high risk women.

Trial design: Multicenter, randomized, placebo-controlled study of 4-OHT gel (2mg per breast) versus placebo in 152 women with heterogeneously or extremely dense breast tissue for 12 months using standard of care imaging, stratified by enrollment site and baseline breast density category. The primary objective of this study is to evaluate the change in percent MD (using Cumulus software) from baseline to the week 52 in women applying 4 mg (2mg per breast) 4-OHT gel versus placebo. The secondary objectives are to compare the Cumulus vs Volpara breast density measurement methods; evaluate the percentage of women with lowering of BIRADS density; estimate percentage of women with ≥ 10% absolute decrease in quantitative MD percentage; explore patient reported experience assessed by BESS questionnaire; laboratory toxicity assessment (F VIII, vWB factor, SHBG, lipid profile); compare the 2D vs. 3D breast density measurement methods to estimate percent change in mammographic breast density; evaluate serum measurements of parent drug and related metabolite levels and factors related to 4-OHT exposures, such as IGF pathway members, CRP, estradiol, and 4-OHT; collect tissue for biomarkers (among women undergoing optional pre- and post-treatment biopsies); examine the persistence in change of mammographic density one year after 4-OHT vs. placebo gel application has stopped.

Eligibility criteria: Inclusion: Women age 40-69 years, or less than 40 years if 5-year breast cancer Gail risk is greater than/equal to 1.66%; heterogeneously or extremely dense breast tissue based on mammography. Exclusion: abnormal uterine bleeding, or prior diagnosis of endometrial hyperplasia, endometrial polyps, or endometrial cancer; prior use of SERMS and AIs, except for a maximum of 3 months and at least 12 months prior.

Statistical methods: Considering an attrition rate of 15%, 128 evaluable women are expected to have both baseline and 52-week measurements of percent MD. With 64 women in each group, there is 80% power to detect a decrease of 6% in the 4-OHT group versus 2% in the placebo group with a common standard deviation of 8% using a two-sided t-test with a significance level of 0.05. Study accrual: Activated January 2018, as of July 1, 2019, 92 patients have been recruited and 79 were randomized.

Citation Format: Banu K. Arun, Gretchen Gierach, Marion E Scoggins, Seema Khan, Sandra S Rao, Judy Garber, Sughra Raza, Nagi B. Kumar, Heather H Han, John Heine, Bethany Niell, Pavani Chalasani, Kimberly Fitzpatrick, Lee G Wilke, Amy Fowler, Heather C Beckwith, Carrie Mays, Saba Abutaseh, Lana Vornik, Oukseub Lee, Eileen Dimond, Marjorie Perloff, Diane Liu, J. Jack Lee, Powell Brown, Brandy Heckman-Stoddard. A randomized, double-blind, placebo-controlled study of 4-hydroxytamoxifen topical gel in women with mammographically dense breasts [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT3-15-02.

Probing optical resonances of silicon nanostructures using tunable-excitation Raman spectroscopy

Optical materials with a high refractive index enable effective manipulation of light at the nanoscale through strong light confinement. However, the optical near field, which is mainly confined inside such high-index nanostructures, is difficult to probe with existing measurement techniques. Here, we exploit the connection between Raman scattering and the stored electric energy to detect resonance-induced near-field enhancements in silicon nanostructures. We introduce a Raman setup with a wavelength-tunable laser, which allows us to tune the Raman excitation wavelength and thereby identify Fabry-Pérot and Mie type resonances in silicon thin films and nanodisk arrays, respectively. We measure the optical near-field enhancement by comparing the Raman response on and off resonance. Our results show that tunable-excitation Raman spectroscopy can be used as a complimentary far-field technique to reflection measurements for nanoscale characterization and quality control. As proof-of-principle for the latter, we demonstrate that Raman spectroscopy captures fabrication imperfections in the silicon nanodisk arrays, enabling an all-optical quality control of metasurfaces.

Clinical Impact of Diagnostic Breast Ultrasound Performed by Generalist Doctors and Nurses in Rwanda

Purpose

Diagnostic breast ultrasound (US) can be an important tool for the early detection of breast cancer in low-resource settings where efficient strategies to refine the likelihood of malignancy among palpable breast masses are needed. However, the feasibility and clinical role of breast US in such settings has not been described. We trained four general practitioners and five nurses in diagnostic breast US at a rural Rwandan district hospital that serves as a cancer referral facility. We examined management plans, biopsy rates, and patient diagnoses after trainee breast US to determine the impact on clinical care.

Methods

We abstracted US assessment forms and medical records to determine outcomes from trainee US during 21 months of in-person and electronic training by Boston-based radiologists. We examined management plans, biopsy rate, cancer detection rate, rate of benign diagnoses, and cancers diagnosed among patients discharged after initial evaluation.

Results

Between January 2016 and September 2017, 307 patients had trainee-performed diagnostic breast US. After US, 158 (51%) were recommended to undergo biopsy, 30 (10%) were recommended to have aspiration/drainage, 49 (16%) were recommended for clinical/US surveillance, one (0.3%) was referred elsewhere, 65 (21%) were discharged, and four—all with no abnormalities on US—had missing recommendations. Of those recommended for initial biopsy, 151 patients (96%) underwent biopsy at that time. Fifty-six patients (37%) were diagnosed with breast cancer, 44 (30%) with fibroadenoma, and 50 (33%) with other benign diagnoses. Among those with breast masses on US (n = 255), 149 patients (58%) underwent biopsy and 55 (22%) were diagnosed with cancer. As of November 2017, all patients ultimately diagnosed with cancer had had a biopsy at their initial visit. No patients who had been discharged or were receiving surveillance had been subsequently diagnosed with cancer.

Conclusion

Diagnostic breast US by general practitioners and nurses has been a useful tool for the evaluation of breast lesions at a rural Rwandan facility and has helped avoid biopsy for 42% of patients with breast masses on US. Clinical follow-up is ongoing to assess longer-term outcomes and examine cancer detection rates and loss-to-follow-up rates among patients not initially biopsied.

AUTHORS' DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST

The following represents disclosure information provided by authors of this manuscript. All relationships are considered compensated. Relationships are self-held unless noted. I = Immediate Family Member, Inst = My Institution. Relationships may not relate to the subject matter of this manuscript. For more information about ASCO's conflict of interest policy, please refer to www.asco.org/rwc or ascopubs.org/jco/site/ifc . Lydia E. Pace Stock or Other Ownership: Firefly Health Sughra Raza Honoraria: Fujifilm Medical Services Travel, Accommodations, Expenses: Fujifilm Medical Services

Early Clinical Impact of Diagnostic Breast Ultrasound Performed by General Practitioners and Nurses in Rwanda

Background: Diagnostic breast ultrasound (US) could be an important tool for early detection of breast cancer in low-resource settings, where efficient strategies to refine the likelihood of malignancy among palpable breast masses are needed. However, the feasibility and clinical role of diagnostic ultrasound in such settings has not been described. We trained 4 general practitioner doctors (GPs) and 5 nurses in diagnostic breast US at a rural district hospital in Rwanda that serves as a cancer referral facility. Aim: Assess management plans, biopsy rates and patient diagnoses after nurse- and GP-performed breast ultrasounds to determine the impact of diagnostic US on clinical care. Methods: We reviewed outcomes from trainees' ultrasounds during 21 months of in-person and electronic training and mentorship by Boston-based radiologists. Trainees' US assessments and management plans were recorded on structured clinical forms. Patient diagnoses and follow-up were extracted from medical records using a standardized data collection form. Among patients who received breast US, we examined a) clinicians' management plans; b) biopsy rate; c) cancer detection rate; c) rate of benign diagnoses; d) cancers diagnosed among patients who were sent home after initial evaluation. Results: Between January 1, 2016 and September 30, 2017, 307 patients with breast concerns had a diagnostic breast US and a documented trainee US assessment. Of these, following their initial US, 158 (51%) were recommended to receive a biopsy, 30 (10%) were recommended to have aspiration/drainage, 49 (16%) were recommended for clinical or US surveillance, 1 (0.3%) was referred to another facility, 65 (21%) were discharged, and 4 (all with no abnormalities on US) had missing recommendations. Of those recommended for biopsy at initial presentation, 151 (96%) had a biopsy at that time. 56 (37%) were diagnosed with breast cancer, 37 (25%) with fibroadenoma, 7 (5%) with lactating adenoma, and 50 (33%) with other benign diagnoses. Among those with breast masses on US (n=255), 149 (58%) received a biopsy and 55 (22%) were diagnosed with cancer. As of November 23, 2017, all patients ultimately diagnosed with cancer had had a biopsy at their initial visit, and no patients who had been discharged or recommended for clinical or radiographic surveillance had been subsequently diagnosed with cancer. Conclusion: Diagnostic breast US by GPs and nurses has been a useful tool in the evaluation of breast lesions, including palpable masses, at a rural cancer facility in Rwanda. Early findings suggest that it has allowed avoidance of biopsy for 42% of patients with breast masses noted on US. Clinical follow-up and evaluation are ongoing to assess longer-term patient outcomes, cancer detection rates among patients who are not initially biopsied, and rates of follow-up among patients recommended to have clinical or radiographic surveillance.

Impact of Training on Rwandan Health Care Staffs’ Skills in Diagnostic Breast Ultrasound

Purpose

Ultrasound (US) is a key tool in the evaluation of palpable breast masses and helps to refine the likelihood of malignancy and need for additional diagnostic studies. US is available in many low-resource settings, but there is little expertise. We launched a breast US training program for general practitioners (GPs) and nurses at a rural Rwandan district hospital that is a cancer referral facility. We assessed the skills of the GPs and nurses in diagnostic breast US after intensive training.

Methods

Four breast radiologists from Boston trained five nurses and four GPs in Rwanda over 9 weeks of in-person training and 21 months of weekly remote mentoring using electronic image review and feedback. During the in-person training, trainees and radiologists evaluated patients separately. Remote assessments were based on emailed image sharing. We compared lesions with radiologist and trainee assessments to calculate trainee sensitivity using the radiologist assessments as the gold standard.

Results

Of 323 breast and axillary lesions assessed by trainees and radiologists, 279 were breast lesions. Of these, 114 (41%) were evaluated by radiologists in person and 165 (59%) through e-mail. Two hundred thirty-seven lesions (85%) were determined to be breast masses by radiologists, 164 of these as solid masses, 25 complex solid/cystic, 15 definite or probable cysts, 31 normal lymph nodes, and two other masses. The sensitivity of trainees’ assessments in identifying solid masses was 90.2% (95% CI, 85.9% to 94.9%) overall. Among trainees who scanned ≥ 10 lesions, mean sensitivity was 90.6% in the first 14 months and 94.0% in the second 9 months, after in-person training ( P = .3, paired t tests). In cases in which radiologists and trainees perceived solid masses (n = 148), trainees’ sensitivity was 81.4% (95% CI, 72.3% to 90.5%) for detecting suspicious masses or probably benign but in need of additional evaluation ( v benign with no additional evaluation needed). Among trainees who scanned ≥ 10 lesions, sensitivity was 79.1% in the first 14 months and 96.2% in the second 9 months ( P = .03, paired t tests).

Conclusion

Nurses and GPs in a rural sub-Saharan African facility built strong skills in diagnostic US with in-person training and remote electronic mentoring. The sensitivity of assessments for identifying suspicious masses demonstrated significant improvement after sustained mentorship. Assessment of the impact of the training on patient care and outcomes is ongoing.

AUTHORS' DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST

The following represents disclosure information provided by authors of this manuscript. All relationships are considered compensated. Relationships are self-held unless noted. I = Immediate Family Member, Inst = My Institution. Relationships may not relate to the subject matter of this manuscript. For more information about ASCO's conflict of interest policy, please refer to www.asco.org/rwc or ascopubs.org/jco/site/ifc . Sughra Raza Honoraria: Fujifilm Medical Services Travel, Accommodations, Expenses: Fujifilm Medical Services

Impact of In-Person and Electronic Training by Breast Radiologists on Rwandan General Practitioners' and Nurses' Skills in Diagnostic Breast Ultrasound

Background: Ultrasound (US) is a key tool in evaluation of palpable breast masses and can help refine the likelihood of malignancy and the need for further diagnostic studies. US technology is available in many low-resource settings, but there are few specialized radiologists. We launched a diagnostic breast ultrasound training program for general practitioner doctors (GPs) and nurses at a rural Rwandan district hospital that serves as a cancer referral facility. Aim: Assess GPs' and nurses' skill in diagnostic breast ultrasound over 23 months of intensive in-person and online supervision and mentorship. Methods: 4 rotating breast radiologists from Brigham and Women's Hospital trained 5 nurses and 4 doctors in Rwanda over 9 weeks of in-person training and 21 months of weekly remote case consultations and mentorship using electronic review of images with emailed feedback. During in-person trainings, trainees and radiologists evaluated patients separately, while radiologists' electronic assessments were based on emailed images and assessments from trainees. Among breast lesions with documented radiologist and trainee assessments, we compared written trainee and radiologist assessments to calculate the sensitivity of trainee assessments, with radiologist assessments as the gold standard. We used paired t-tests to examine whether the sensitivity varied between the first 14 months (stage I) and the last 9 months (stage 2), after the final in-person training. Results: Of 323 breast and axillary lesions assessed by trainees and radiologists, 279 were breast lesions. Of these, 114 (41%) were evaluated by radiologists in-person, and 165 (59%) through electronic evaluation. 237 (85%) were determined to be breast masses by the radiologists, with 164 of these solid masses, 25 complex solid/cystic lesions, 15 definite or probable simple cysts, 31 normal intramammary lymph nodes, and 2 other masses. Sensitivity of trainees' assessments for identifying a solid mass was 90.2% (95% CI 85.9-94.9) overall. Among trainees who scanned ≥ 10 lesions each, mean sensitivity was 90.6% in stage I, and 94.0% in stage 2 ( P = 0.3). In cases where both radiologists and trainees perceived solid masses (n=148), trainees' assessments had a sensitivity of 81.4% (95% CI 72.3-90.5) overall for detecting masses suspicious for malignancy, or probably benign but needing further evaluation (versus benign with no further evaluation needed). Among trainees who scanned ≥ 10 lesions each, sensitivity was 79.1% during stage I and 96.2% during the stage 2 ( P = 0.03). Conclusion: Nurses and GPs in a rural sub-Saharan African facility built strong skills in diagnostic ultrasound over 23 months of combined in-person training and distance learning via electronic case reviews. The sensitivity of their assessments for identifying masses concerning for malignancy showed significant improvement after sustained mentorship. Assessment of impact on patient care and outcomes is ongoing.

Optimizing Success and Avoiding Mishaps in the Most Difficult Image-guided Breast Biopsies

Breast cancer is an increasing challenge in developed and limited resource areas of the world. Early detection of breast cancer offers the best chance for optimal care and best outcomes. A critical step in early detection is to obtain efficient and accurate tissue diagnoses. Although image-guided core needle breast biopsies are usually straightforward for experienced breast imagers, there are some not uncommon scenarios that present particular challenges. In this review article we will discuss these difficult situations and offer our tried and true methods to ensure safe and successful biopsies, while using stereotactic, ultrasound, and MRI guidance.

Population-based cohort study of variation in the use of emergency cholecystectomy for benign gallbladder diseases

Background

The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals.

Methods

Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2).

Results

Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals.

Conclusion

Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care.

The Breast Imager's Approach to Nonmammary Masses at Breast and Axillary US: Imaging Technique, Clues to Origin, and Management

Ultrasonography (US) of the breast and axilla is primarily used to evaluate a symptomatic patient or to further investigate findings identified with other imaging modalities. Breast imagers are generally familiar with US evaluation of level I, II, and III axillary lymph nodes in the diagnosis and staging of breast cancer. However, the axilla contains nonlymphatic tissue as well, including muscle, fat, and vascular and neurologic structures, and anatomically the breast lies on the chest wall. Therefore, lesions of nonmammary and non-lymph node origin in the axilla or chest wall are not infrequently encountered during US evaluation of the breast or axilla. In fact, such lesions may be the reason that the patient presents to the breast imaging department for evaluation. Understanding the anatomy of the chest wall and axilla and using a systematic US approach will help radiologists expedite accurate diagnosis, suggest optimal additional imaging, and streamline appropriate clinical referral. Key imaging features of nonmammary non-lymph node masses are highlighted, and case examples are provided to illustrate these features. Appropriate patient management is critical in these cases because referral to a breast surgeon may not be the best next step. Depending on institutional referral patterns, other subspecialty surgeons will be involved. Online supplemental material is available for this article.

Avoiding Pitfalls, Maximizing Success at Image-guided Breast Interventions: A Pictorial Review

Imaging and image-guided interventions have become increasingly important in the workup and treatment of breast lesions in the past 2 decades. Radiologists should be aware of potential pitfalls during the workup, the procedure itself, and in the postprocedure follow-up. In this pictorial review, we illustrate challenges related to technique and interpretation related to breast interventions, and suggest ways to maximize success.

Breast density: clinical implications and assessment methods

Breast density assessment is an important component of the screening mammography report and conveys information to referring clinicians about mammographic sensitivity and the relative risk for developing breast cancer. These topics have gained substantial attention because of recent legislation in several states that requires patients to be informed of dense breast tissue and the potential for associated breast cancer risk and decreased mammographic sensitivity. Because of the considerable implications of diagnosing a woman with dense breast tissue, radiologists should strive to be as consistent as possible when assessing breast density. Commonly used methods of breast density assessment range from subjective visual estimation to quantitative calculations of area and volume density percentages made with complex computer algorithms. The basic principles of currently available commercial methods of calculating fibroglandular density are described and illustrated. There is no criterion standard for determining breast density, but understanding the pros and cons of the various assessment methods will allow radiologists to make informed decisions. Radiologists should understand the basic factors involved in breast density assessment, the changes related to density assessment described in the fifth edition of the American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) lexicon, and the capabilities of currently available software. Online supplemental material is available for this article.