Screening mammography frequency following dense breast notification among a predominantly Hispanic/Latina screening cohort

PURPOSE

Nationally legislated dense breast notification (DBN) informs women of their breast density (BD) and the impact of BD on breast cancer risk and detection, but consequences for screening participation are unclear. We evaluated the association of DBN in New York State (NYS) with subsequent screening mammography in a largely Hispanic/Latina cohort.

METHODS

Women aged 40-60 were surveyed in their preferred language (33% English, 67% Spanish) during screening mammography from 2016 to 2018. We used clinical BD classification from mammography records from 2013 (NYS DBN enactment) through enrollment (baseline) to create a 6-category variable capturing prior and new DBN receipt (sent only after clinically dense mammograms). We used this variable to compare the number of subsequent mammograms (0, 1, ≥ 2) from 10 to 30 months after baseline using ordinal logistic regression.

RESULTS

In a sample of 728 women (78% foreign-born, 72% Hispanic, 46% high school education or less), first-time screeners and women who received DBN for the first time after prior non-dense mammograms had significantly fewer screening mammograms within 30 months of baseline (Odds Ratios range: 0.33 (95% Confidence Interval (CI) 0.12-0.85) to 0.38 (95% CI 0.17-0.82)) compared to women with prior mammography but no DBN. There were no differences in subsequent mammogram frequency between women with multiple DBN and those who never received DBN. Findings were consistent across age, language, health literacy, and education groups.

CONCLUSION

Women receiving their first DBN after previous non-dense mammograms have lower mammography participation within 2.5 years. DBN has limited influence on screening participation of first-time screeners and those with persistent dense mammograms.

Role of Online Patient Portal Self-Scheduling and Self-Referral Pathways to Decrease Health Disparity for Screening Mammography

PURPOSE

The aim of this study was to assess the rate of self-scheduling and self-referral for screening mammography and to assess sociodemographic factors associated with their use in an academic health care system in southern California.

METHODS

Patients scheduled for screening mammography between February 1, 2021, and September 20, 2022, were included in this retrospective study. Multivariable logistic regression models were used to assess associations among sociodemographic factors, self-referral, and online self-scheduling pathways.

RESULTS

In total, 22,306 patients were scheduled for screening mammography (mean age, 59 years; 66.8% White, 20.4% Asian, and 20.6% Hispanic). Overall, 3,566 (16.0%) used online self-scheduling, and 1,232 (5.5%) self-referred for screening mammography. Patients 70 years or older (versus 50 years or younger) (odds ratio [OR], 0.41; 95% confidence interval [CI], 0.34-0.51), Spanish (versus English) speakers (OR, 0.22; 95% CI, 0.16-0.31), and those on Medicaid (versus commercially insured) (OR, 0.71; 95% CI, 0.50-0.99) were less likely to self-schedule. Hispanic patients (versus non-Hispanic) (OR, 1.39; 95% CI, 1.20-1.61), Asian patients (versus White) (OR, 1.64; 95% CI, 1.46-1.85), and patients residing in the most (versus least) disadvantaged neighborhoods (OR, 1.16; 95% CI, 1.02-1.33) were more likely to self-schedule. Furthermore, patients 70 years or older (versus 50 or younger) (OR, 0.70; 95% CI, 0.52-0.93) and Spanish speakers (OR, 0.05; 95% CI, 0.03-0.09) were less likely to self-refer, whereas Black patients (versus White) (OR, 1.89; 95% CI, 1.30-2.75), patients on Medicaid (versus commercially insured) (OR, 3.70; 95% CI, 2.65-5.13), and patients living in the most (versus least) disadvantaged neighborhoods (OR, 1.52; 95% CI, 1.27-1.82) were more likely to self-refer.

CONCLUSIONS

Sociodemographic differences in online patient portal use and self-referral for screening mammography suggest that the two pathways have been successful in addressing some of the existing scheduling barriers and are a step toward closing the disparity gap.

Breast cancer surveillance in BRCA positive Sri Lankan women: health equity for a high-risk group at a limited resource setting

BACKGROUND

BRCA1 and BRCA2 pathogenic variants account for 90% of hereditary breast malignancies, incurring a lifetime breast cancer risk of 85% and 40-45% respectively, in affected individuals. Well-resourced health care settings offer genetic counselling and genetic screening for susceptible individuals, followed by intense breast cancer surveillance programmes for those identified at high risk of breast cancer. Such high standards of care are not available in countries with limited resources. This study assessed breast cancer surveillance behaviors among a cohort of BRCA positive Sri Lankan women.

METHODS

A retrospective case review of all patients diagnosed with pathogenic variants in BRCA1 and BRCA2 genes from 2015 to 2022 at the Human Genetics Unit, Faculty of Medicine, University of Colombo was carried out followed by telephone interviews of the respondents. Patients who were not contactable, deceased, undergone bilateral mastectomy and males were excluded from the interview component of the study. Standard descriptive statistics were used to analyze the data using SPSS statistics version 25.

RESULTS

Only 25 patients were diagnosed during the study period:14/25 women responded (6/25 deceased, 3/25 non-contactable; 2/25 excluded). 71.4% (10/14) had performed breast self-examination during the preceding month; 35.7% (5/14) had a clinical breast examination (CBE), and 50% (7/14) had undergone a screening/diagnostic mammogram during the last one year. 28.5% (4/14) had undergone both mammography and CBE; 21.45% (3/14) mammogram only, 7.1% (1/14) had CBE only. 42.8%(6/14) had not undergone any surveillance(mammography, CBE or MRI). None had dual screening with mammogram and MRI. 85.71% (12/14) women expressed willingness to participate in a regular screening programme if made available.

CONCLUSION

Fifty percent of BRCA1/2 positive women in our study had not undergone annual imaging-based surveillance by mammography or MRI, and none had undergone annual dual screening with mammography and MRI, indicating inadequate breast cancer surveillance in this high-risk group.

Attitudes of Gynecologists toward Referral of Women to Breast Imaging Clinics for Breast Cancer Screening or Diagnosis

PURPOSE

To investigate whether gynecologists considered the age of women when requesting ultrasound (US) and/or mammography examinations. Furthermore, to determine in which situations gynecologists referred patients to breast imaging clinics for breast examinations, and aimed to establish the reasons behind cases of non-referral.

MATERIALS AND METHODS

A questionnaire-based survey was conducted from February to April 2023 among gynecologists practicing at government, university, or private hospitals/centers. The participants were contacted through an online Web link ( www.googledocs.com ).

RESULTS

The questionnaire was completed by 80 gynecologists. In total, 96.2% of the participants referred women to breast imaging clinics. The proportion of female physicians (70%) was higher than that of male physicians, and 55% were younger than 40 years. Menopause, hormone replacement therapy, and hereditary/genetic or familial breast cancer were the most commonly considered risk factors when referring women. Overall, 75% of participants requested mammography for women aged ≥ 40 years. For women between the ages of 30 and 40, mammography was requested by 40% of physicians. For women younger than 30, US was requested by 70% of participants, while a small number of participants (7.5%) requested mammography if deemed necessary.

CONCLUSION

Gynecologists tend to refer women to breast imaging clinics for screening rather than for diagnostic purposes. Female gynecologists have a higher tendency for referral, especially if there is a risk factor involved. Seminars or courses at gynecology conferences can be organized by experienced breast imaging specialists to give detailed information about breast cancer and examination methods according to patient age. This will ensure better breast assessment.

Feasibility of predicting a screening digital breast tomosynthesis recall using features extracted from the electronic medical record

PURPOSE

Tools to predict a screening mammogram recall at the time of scheduling could improve patient care. We extracted patient demographic and breast care history information within the electronic medical record (EMR) for women undergoing digital breast tomosynthesis (DBT) to identify which factors were associated with a screening recall recommendation.

METHOD

In 2018, 21,543 women aged 40 years or greater who underwent screening DBT at our institution were identified. Demographic information and breast care factors were extracted automatically from the EMR. The primary outcome was a screening recall recommendation of BI-RADS 0. A multivariable logistic regression model was built and included age, race, ethnicity groups, family breast cancer history, personal breast cancer history, surgical breast cancer history, recall history, and days since last available screening mammogram.

RESULTS

Multiple factors were associated with a recall on the multivariable model: history of breast cancer surgery (OR: 2.298, 95% CI: 1.854, 2.836); prior recall within the last five years (vs no prior, OR: 0.768, 95% CI: 0.687, 0.858); prior screening mammogram within 0-18 months (vs no prior, OR: 0.601, 95% CI: 0.520, 0.691), prior screening mammogram within 18-30 months (vs no prior, OR: 0.676, 95% CI: 0.520, 0.691); and age (normalized OR: 0.723, 95% CI: 0.690, 0.758).

CONCLUSIONS

It is feasible to predict a DBT screening recall recommendation using patient demographics and breast care factors that can be extracted automatically from the EMR.

Experience of a single healthcare system with screening mammography before and after COVID-19 shutdown

PURPOSE

To evaluate COVID-19's longitudinal impact on screening mammography volume trends.

METHODS

HIPAA-compliant, IRB-approved, single institution, retrospective study of screening mammogram volumes before (10/21/2016-3/16/2020) and greater than two years after (6/17/2020-11/30/2022) a state-mandated COVID-19 shutdown (3/17/2020-6/16/2020) were reviewed. A segmented quasi-poisson linear regression model adjusting for seasonality and network and regional population growth compared volume trends before and after the shutdown of each variable: age, race, language, financial source, risk factor for severe COVID-19, and examination location.

RESULTS

Adjusted model demonstrated an overall increase of 65 screening mammograms per month before versus a persistent decrease of 5 mammograms per month for >2 years after the shutdown (p < 0.0001). In subgroup analysis, downward volume trends were noted in all age groups <70 years (age < 50: +9/month before vs. -7/month after shutdown; age 50-60: +17 vs. -7; and age 60-70: +21 vs. -2; all p < 0.001), those identifying as White (+55 vs. -8, p < 0.0001) and Black (+4 vs. +1, p = 0.009), all financial sources (Medicare: +22 vs. -3, p < 0.0001; Medicaid: +5 vs. +2, p = 0.006; private insurance/self-pay: +38 vs. -4, p < 0.0001), women with at least one risk factor for severe COVID-19 (+30 vs. -48, p < 0.0001), and screening mammograms performed at a hospital-based location (+48 vs. -14, p = 0.0001).

CONCLUSION

The screening mammogram volume trend more than two years after the COVID-19 shutdown has continued to decline for most patient populations. Findings highlight the need to identify additional areas for education and outreach.

The long-term psychosocial consequences of screen-detected ductal carcinoma in situ and invasive breast cancer

OBJECTIVE

Ductal carcinoma in situ (DCIS) is a risk factor for invasive breast cancer (IBC). The prognosis of DCIS is considerably better than for IBC, yet women do not distinguish between the threat. We aimed to compare the psychosocial consequences of screen-detected DCIS and IBC, and to examine this comparison over time.

METHODS

We surveyed a Danish mammography-screening cohort from 2004 to 2018. We assessed outcomes at six-time points: baseline, 1, 6, 18, 36 months, and 14 years after the screening. We measured psychosocial consequences with the Consequences Of Screening - Breast Cancer (COS-BC): a condition-specific questionnaire that is psychometrically validated and encompasses 14 psychosocial dimensions. We used weighted linear models with generalized estimating equations to compare responses between groups. We used a 1% level of significance.

RESULTS

170 out of 1309 women were diagnosed with breast cancer (13.0%). 23 were diagnosed with DCIS (13.5%) and 147 with IBC (86.5%). From baseline to six months after diagnosis, there were no significant differences between women with DCIS and IBC. However, mean scores indicated that IBC generally was more affected than DCIS. After six months, we observed that women with DCIS and IBC might be affected differently in the long term; mean scores and mean differences showed that IBC were more affected on some scales, while DCIS were on others.

CONCLUSION

Overall, the DCIS and IBC experienced similar levels of psychosocial consequences. Women might benefit from renaming DCIS to exclude cancer nomenclature.

Prioritizing Screening Mammograms for Immediate Interpretation and Diagnostic Evaluation on the Basis of Risk for Recall

PURPOSE

The aim of this study was to develop a prioritization strategy for scheduling immediate screening mammographic interpretation and possible diagnostic evaluation.

METHODS

A population-based cohort with screening mammograms performed from 2012 to 2020 at 126 radiology facilities from 7 Breast Cancer Surveillance Consortium registries was identified. Classification trees identified combinations of clinical history (age, BI-RADS® density, time since prior mammogram, history of false-positive recall or biopsy result), screening modality (digital mammography, digital breast tomosynthesis), and facility characteristics (profit status, location, screening volume, practice type, academic affiliation) that grouped screening mammograms by recall rate, with ≥12/100 considered high and ≥16/100 very high. An efficiency ratio was estimated as the percentage of recalls divided by the percentage of mammograms.

RESULTS

The study cohort included 2,674,051 screening mammograms in 925,777 women, with 235,569 recalls. The most important predictor of recall was time since prior mammogram, followed by age, history of false-positive recall, breast density, history of benign biopsy, and screening modality. Recall rates were very high for baseline mammograms (21.3/100; 95% confidence interval, 19.7-23.0) and high for women with ≥5 years since prior mammogram (15.1/100; 95% confidence interval, 14.3-16.1). The 9.2% of mammograms in subgroups with very high and high recall rates accounted for 19.2% of recalls, an efficiency ratio of 2.1 compared with a random approach. Adding women <50 years of age with dense breasts accounted for 20.3% of mammograms and 33.9% of recalls (efficiency ratio = 1.7). Results including facility-level characteristics were similar.

CONCLUSIONS

Prioritizing women with baseline mammograms or ≥5 years since prior mammogram for immediate interpretation and possible diagnostic evaluation could considerably reduce the number of women needing to return for diagnostic imaging at another visit.

Failure of stereotactic core needle biopsy in women recalled for suspicious calcifications at screening mammography: frequency, causes, and final outcome in a multi-institutional, observational follow-up study

OBJECTIVES

We determined the failure rate of stereotactic core needle biopsy (SCNB) and its causes and final outcome in women recalled for calcifications at screening mammography.

METHODS

We included a consecutive series of 624,039 screens obtained in a Dutch screening region between January 2009 and July 2019. Radiology reports and pathology results were obtained of all recalled women during 2-year follow-up.

RESULTS

A total of 3495 women (19.6% of 17,809 recalls) were recalled for suspicious calcifications. SCNB was indicated in 2818 women, of whom 12 had incomplete follow-up and another 12 women refused biopsy. DCIS or invasive cancer was diagnosed in 880 of the remaining 2794 women (31.5%). SCNB failed in 62 women (2.2%, 36/2794). These failures were mainly due to a too posterior (n = 30) or too superficial location (n = 17) of the calcifications or calcifications too faint for biopsy (n = 13). Of these 62 women, 10 underwent surgical biopsy, yielding one DCIS (intermediate grade) and two invasive cancers (one intermediate grade and one high grade) and another two women were diagnosed with DCIS (both high grade) at follow-up. Thus, the malignancy rate after SCNB failure was 8.1% (5/62). Calcifications were depicted neither at SCNB specimen radiography nor at pathology in 16 women after (repeated) SCNB (0.6%, 31/2732). None of them proved to have breast cancer at 2-year follow-up.

CONCLUSIONS

The failure rate of SCNB for suspicious calcifications is low but close surveillance is warranted, as breast cancer may be present in up to 8% of these women.

KEY POINTS

• The failure rate of stereotactic core needle biopsy (SCNB) for calcifications recalled at screening mammography was 2.2%. • Failures were mainly due to calcifications that could not be reached by SCNB or calcifications too faint for biopsy. • The management after failed SCNB was various. At least, close surveillance with a low threshold for surgical biopsy is recommended as breast cancer may be present in up to 8% of women with SCNB failure.

Racial and socioeconomic inequities in breast cancer screening before and during the COVID-19 pandemic: analysis of two cohorts of women 50 years +

BACKGROUND

Routine screening mammography at two-year intervals is widely recommended for the prevention and early detection of breast cancer for women who are 50 years + . Racial and other sociodemographic inequities in routine cancer screening are well-documented, but less is known about how these long-standing inequities were impacted by the disruption in health services during the COVID-19 pandemic. Early in the pandemic, cancer screening and other prevention services were suspended or delayed, and these disruptions may have had to disproportionate impact on some sociodemographic groups. We tested the hypothesis that inequities in screening mammography widened during the pandemic.

METHODS

A secondary analysis of patient data from a large state-wide, non-profit healthcare system in Washington State. Analyses were based on two mutually exclusive cohorts of women 50 years or older. The first cohort (n = 18,197) were those women screened in 2017 who would have been due for repeat screening in 2019 (prior to the pandemic's onset). The second cohort (n = 16,391) were women screened in 2018 due in 2020. Explanatory variables were obtained from patient records and included race/ethnicity, age, rural or urban residence, and insurance type. Multivariable logistic regression models estimated odds of two-year screening for each cohort separately. Combining both cohorts, interaction models were used to test for differences in inequities before and during the pandemic.

RESULTS

Significant sociodemographic differences in screening were confirmed during the pandemic, but these were similar to those that existed prior. Based on interaction models, women using Medicaid insurance and of Asian race experienced significantly steeper declines in screening than privately insured and white women (Odds ratios [95% CI] of 0.74 [0.58-0.95] and 0.76 [0.59-0.97] for Medicaid and Asian race, respectively). All other sociodemographic inequities in screening during 2020 were not significantly different from those in 2019.

CONCLUSIONS

Our findings confirm inequities for screening mammograms during the first year of the COVID-19 pandemic and provide evidence that these largely reflect the inequities in screening that were present before the pandemic. Policies and interventions to tackle long-standing inequities in use of preventive services may help ensure continuity of care for all, but especially for racial and ethnic minorities and the socioeconomically disadvantaged.

Clinicopathological characteristics and survival results of patients with ultralow risk breast cancer

BACKGROUND AND OBJECTIVE

To identify subgroups with good progress over an extended period, we used diagnostic screening, tumour palpability, tumour phenotype, and node involvement.

PATIENTS AND METHODS

We identified patients with good progress by means of a descriptive, observational and retrospective study.

RESULTS

Of 746 patients diagnosed with node-negative breast cancer between 2001 and 2015: 110 (14.75%) had non-palpable screening-diagnosed tumours; 88 (80%) were endocrine-sensitive, 10 (9.10%) were triple-negative and 11 (10%) were HER2. Only 3 patients developed metastases, and there were 4 deaths: 2 from breast cancer and 2 from other causes. The distant recurrence-free interval (DRFI) was 95.60%: 100% in 34 endocrine-sensitive histological grade 1 (equivalent to luminal A) tumours, and 94.40% (95% CI 86.76-102.04) in 54 grade 2-3 (luminal B) tumours. In triple-negative and HER2 cases, it was 100%. In tumours <1 cm it was 100%, and >1 cm it was 95.50% (95% CI 79.42-100.98).

CONCLUSIONS

Patients with non-palpable tumours detected by mammogram screening have ultralow risk. The good progress in the luminal A, triple-negative, HER2, and less than 1 cm subgroups may explain the efficacy of the treatment but it also makes them candidates to de-escalation of their treatment.

Intra- and inter-rater reliability of compressed breast thickness, applied force, and pressure distribution in screening mammography

Background

Ensuring equivalent and reproducible breast compression between mammographic screening rounds is important for the diagnostic performance of mammography, yet the extent to which screening mammography positioning and compression is reproducible for the individual woman is unknown.

Purpose

To investigate the intra- and inter-rater reliability of breast compression in screening mammography.

Materials and Methods

Eleven breast-healthy women participated in the study. Two experienced radiographers independently positioned and compressed the breasts of each participant in two projections—right craniocaudal and left mediolateral oblique—and at two time points. The spatial pressure distribution on the compressed breast was measured using a pressure sensor matrix. Applied force, compressed breast thickness, force in field of view, contact area, mean pressure, and center of mass (anterio-posterior and mediolateral axes) were measured. The reliabilities of the measures between the time points for each radiographer (intra-rater reliability) and between the radiographers (inter-rater reliability) were analyzed using the intraclass correlation coefficient (ICC).

Results

Intra- and inter-rater reliabilities from both projections demonstrated good to excellent ICCs (≥0.82) for compressed breast thickness, contact area, and anterio-posterior center of mass. The other measures produced ICCs that varied from poor (≤0.42) to excellent (≥0.93) between time points and between radiographers.

Conclusion

Intra- and inter-rater reliability of breast compression was consistently high for compressed breast thickness, contact area, and anterio-posterior center of mass but low for mediolateral center of mass and applied force. Further research is needed to establish objective and clinically useful parameters for the standardization of breast compression.

Reducing False-Positive Biopsies using Deep Neural Networks that Utilize both Local and Global Image Context of Screening Mammograms

Breast cancer is the most common cancer in women, and hundreds of thousands of unnecessary biopsies are done around the world at a tremendous cost. It is crucial to reduce the rate of biopsies that turn out to be benign tissue. In this study, we build deep neural networks (DNNs) to classify biopsied lesions as being either malignant or benign, with the goal of using these networks as second readers serving radiologists to further reduce the number of false-positive findings. We enhance the performance of DNNs that are trained to learn from small image patches by integrating global context provided in the form of saliency maps learned from the entire image into their reasoning, similar to how radiologists consider global context when evaluating areas of interest. Our experiments are conducted on a dataset of 229,426 screening mammography examinations from 141,473 patients. We achieve an AUC of 0.8 on a test set consisting of 464 benign and 136 malignant lesions.

Implant deformity on screening mammography, an unusual presentation of breast implant associated lymphoma

Breast implant associated anaplastic large cell lymphoma (BIA-ALCL) is a rare condition related to textured breast implants. Recognition of characteristic imaging and pathological features are important, given the absence of symptoms can delay diagnosis, as illustrated by this case. Late-onset peri-implant effusion is commonly encountered whilst an associated mass or lymphadenopathy are rare. Clinical and radiological suspicion enables dedicated pathology work-up for diagnosis. Ultrasound is vital for initial work-up whilst MRI and PET-CT assist in staging. Surgical explantation is followed by adjuvant chemo-radiotherapy according to disease extent.

Cost-effectiveness of screening mammography in a low income country: a Markov simulation analysis

Background

Breast cancer is the most common cancer diagnosed in women. Screening mammography is the only imaging screening study for breast cancer with a proven. mortality benefit. This study aims to analyze the cost-effectiveness of screening mammography in Ethiopia.

Methods

Multistate Markov model was used for computer simulation to estimate cost and health benefits of screening mammography interventions for age-group of 40–49 years and 50–59 years. The cost-effectiveness analysis was made for 4 policies based on where the screening mammography procedures were conducted: government institution only, the private institution only, 50% ratio for each, and 10% private institution policy. Outputs were expressed in total cost, life-years gained (LYG) incremental cost-effectiveness ratio (ICER), and incremental net monetary benefit (INMB).

Results

All 4 policies of annual screening mammography failed to achieve acceptable ICER and lead to a net loss in INMB. The lowest ICER value was for government institution-only policy with 3510.3 USD/LYG and 3224.9 USD/LYG both above the cost-effectiveness threshold of 2808.5 USD. The cost per single death averted for each group was 110,206.7 USD and 77,088.2 USD for age-group 40–49 years and 50–59 years respectively.

Conclusion

Screening mammography could not be shown to be cost-effective in Ethiopia with the current low cost-effectiveness threshold. Alternative screening approach like annual clinical breast examination may need to be investigated.

Monochromatic X-rays: The future of breast imaging

PURPOSE

To present details about the innovative and disruptive technology of monochromatic X-rays and its application to breast imaging.

METHODS

To analyze results of studies done using a prototype system for breast imaging that generates monochromatic X-rays through fluorescence emission. To assess signal-to-noise ratio (SNR) as a measure of image quality at different doses in breast phantoms of different sizes and review the comparison of parameters with a standard mammography system.

RESULTS

Monochromatic X-rays reduce the radiation dose per mammogram by a factor of 5 to 10 times. For phantom simulating thick breast (9 cm), the SNR for monochromatic system was 2.6 times higher and the dose 4.2 times lower than the respective values obtained with the conventional system within the same 5 mm × 5 mm square area of the 100% glandular step wedge. For the conventional broadband system to equal the SNR of the monochromatic system, it would require a dose of 19 mGy, 29 times higher than the dose delivered by the monochromatic system. Contrast-enhanced digital mammography with monochromatic X-rays is shown to provide a simpler and more effective technique at substantially lower radiation dose.

CONCLUSIONS

Lowering radiation dose by a factor of 5 to 10 while maintaining image quality implies a major reduction in total exposure from breast cancer screening and dramatically less risk of radiation-induced cancers in at-risk women. The high SNRs for very thick breast phantoms provide strong evidence that screening with lower breast compression is possible while maintaining image quality.

Outcomes of screening mammography performed prior to fertility treatment in women ages 40-49

OBJECTIVE

There are currently various conflicting recommendations for breast cancer screening with mammography in women between ages 40-49. There are no specific guidelines for breast cancer screening in women of this age group prior to assisted reproductive technology (ART) for the treatment of infertility. The purpose of our study was to evaluate outcomes of screening mammography, specifically ordered for the purpose of pre-fertility treatment clearance in women aged 40-49 years old.

MATERIALS AND METHODS

This was an IRB approved retrospective study of women aged 40-49 presenting for screening mammography prior to ART between January 2010 and October 2018. Clinical history, imaging, and pathology results were gathered from the electronic medical record. Descriptive statistics were performed.

RESULTS

Our study cohort consisted of 118 women with a mean age of 42 years (range 40-49). Sixteen of 118 (14%) women were recalled from screening for additional diagnostic work-up. Five of the 16 (31%) were recommended for biopsy (BI-RADS 4 or 5). One of 5 biopsies yielded a malignant result (PPV 20%). Overall cancer detection rate was 0.85% or 8.5 women per 1000 women screened. The single cancer in this cohort was an ER+ PR+ HER2- invasive ductal carcinoma.

CONCLUSION

Screening mammography in women 40-49 performed prior to initiation of ART may identify asymptomatic breast malignancy. In accordance with ACR and SBI guidelines to screen women of this age group, women of this age group should undergo screening mammography prior to ART.

Variations in pathways and resource use in follow-up after abnormal mammography screening: a nationwide register-based study

PURPOSE

Mammography screening reduces breast cancer mortality, but a successful screening programme depends on both high participation and a sufficient follow-up of abnormalities. This study investigated patterns of follow-up after abnormal screening mammography in Denmark, and whether the variation was associated with health care resource use.

METHODS

We included 19,458 women aged 50-69 years with an abnormal screening mammography during a 3-year period of 2014-2016. Women were followed until the end of 2018. Their follow-up pathway was categorized in terms of the timeliness, appropriateness (i.e. whether all recommended diagnostic tests were utilized), and the ratio of benign vs. malignant surgeries. Further, we estimated health care resource use including post-diagnostic imaging and surgery procedures.

RESULTS

Ninety-seven percent of women had a diagnostic follow-up test within 6 months and 94% of those had diagnostic procedures in accordance with the recommendations. The proportion with timely follow-up (i.e. within 1 month) was 83%, but varied significantly between administrative regions (p < 0.001), and also between women with a screen-detected cancer and those with a false-positive mammogram (87% vs. 81%, p < 0.001). The ratio between having a benign versus a malignant surgery was 1:8, but it varied depending on which tests were used for diagnosis. The average number of procedures was, generally, in accordance with the recommendations.

CONCLUSION

In most cases, follow-up after abnormal screening mammography followed national recommendations. We nevertheless found that this was not always the case in certain subgroups and administrative regions.

Detection rate of breast malignancy of needle localization biopsy of breast microcalcification

OBJECTIVE

The current study aimed to retrospectively assess the cancer detection rate of needle localization biopsy of breast microcalcifications undetectable on sonography.

MATERIALS AND METHODS

Patients who underwent mammography-guided needle localization biopsy of breast microcalcifications undetectable on sonography from January 2005 to December 2017 were included in the study. Patients with incomplete medical records were excluded from the study. Patient mammograms were categorized using the Breast Imaging-Reporting and Data System (BI-RADS) assessment criteria. The percentages of benign and malignant lesions were determined by pathological examination of surgically recovered specimens. Correlation between preoperative imaging assessment and final diagnosis was investigated, and the complications associated with the procedures were recorded.

RESULTS

A total of 301 needle-localized biopsies were performed under mammographic guidance. The mean age of the patients was 58.18 ± 7.73 years. The overall ductal carcinoma in situ (DCIS) and cancer detection rate was 23.3%. The proportion of patients with BI-RADS 0 category and undergoing second mammography was higher in the DCIS and cancer group. A total of 227 patients did not undergo second mammography. Of these patients, 70 demonstrated BI-RADS 4 category, 34 were diagnosed with DCIS, and 5 were diagnosed with breast cancer during subsequent follow-up.

CONCLUSION

Needle-localized excision of microcalcifications undetectable on sonography has high detection rate for early stage of breast cancer with low risk of associated complications. Regular mammography is a satisfactory follow-up tool for female patients with microcalcifications in the breasts. Additional studies should be performed to compare between needle-localized excision and vacuum-assisted breast biopsy.

Impact of the COVID-19 pandemic on breast cancer screening volumes and patient screening behaviors

Purpose

In order to facilitate targeted outreach, we sought to identify patient populations with a lower likelihood of returning for breast cancer screening after COVID-19-related imaging center closures.

Methods

Weekly total screening mammograms performed throughout 2019 (baseline year) and 2020 (COVID-19-impacted year) were compared. Demographic and clinical characteristics, including age, race, ethnicity, breast density, breast cancer history, insurance status, imaging facility type used, and need for interpreter, were compared between patients imaged from March 16 to October 31 in 2019 (baseline cohort) and 2020 (COVID-19-impacted cohort). Census data and an online map service were used to impute socioeconomic variables and calculate travel times for each patient. Logistic regression was used to identify patient characteristics associated with a lower likelihood of returning for screening after COVID-19-related closures.

Results

The year-over-year cumulative difference in screening mammogram volumes peaked in week 21, with 2962 fewer exams in the COVID-19-impacted year. By week 47, this deficit had reduced by 49.4% to 1498. A lower likelihood of returning for screening after COVID-19-related closures was independently associated with younger age (odds ratio (OR) 0.78, p < 0.001), residence in a higher poverty area (OR 0.991, p = 0.014), lack of health insurance (OR 0.65, p = 0.007), need for an interpreter (OR 0.68, p = 0.029), longer travel time (OR 0.998, p < 0.001), and utilization of mobile mammography services (OR 0.27, p < 0.001).

Conclusion

Several patient factors are associated with a lower likelihood of returning for screening mammography after COVID-19-related closures. Knowledge of these factors can guide targeted outreach to vulnerable patients to facilitate breast cancer screening.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10549-021-06252-1.

Impact of Age, Race, and Socioeconomic Status on Women's Perceptions and Preferences Regarding Communication of Estimated Breast Cancer Risk

RATIONALE AND OBJECTIVES

Performing breast cancer risk assessment at the time of screening mammography has potential to increase high-risk identification, appropriate supplemental screening, and risk management. The study's goal is to investigate women's interest in risk assessment and preferred method of risk communication in a diverse patient population.

MATERIALS AND METHODS

Surveys in English and five non-English languages were distributed to women presenting for screening mammography at eight screening mammography facilities between February and May 2019 to assess their interest in risk assessment, preferred method, and level of detail of estimated risk communication in hypothetical scenarios where estimated risks are average and elevated.

RESULTS

Among 683 survey respondents, 592 (87%) expressed interest in learning about their estimated lifetime risk of breast cancer. Controlling for age, race/ethnicity, and education, women with higher income were more interested in risk assessment than comparison group (p<0.05). The most preferred method of average risk communication was by a mailed letter accompanying mammographic results (57%), but more women exclusively preferred face-to-face communications of elevated risk than of average risk estimate (191, 28% vs. 128, 19%, p<0.0001). Phone communication was more preferred by younger women, electronic communication was less preferred by older women and those with lower income, and non-Hispanic blacks and older women preferred less detailed communication (p<0.05).

CONCLUSION

Sociodemographic factors influence women's interest in risk assessment and preference in risk communication about breast cancer. Screening Mammogram facilities implementing risk assessment should consider risk communication strategies that are most effective for their patient population.

Association between radiologists' and facilities' characteristics and mammography screening detection of ductal carcinoma in situ

PURPOSE

The aim of our study was, first, to measure association between radiologists and facilities characteristics and DCIS detection. Second, to assess whether those characteristics affect differently the likelihood of detection of DCIS versus invasive breast cancer. When applicable, we examined whether the identified characteristics were similarly associated with low-grade and high-grade DCIS detection.

METHODS

This retrospective cohort study included 1,750,002 digital screening mammograms (2145 screen-detected DCIS) performed in the Quebec breast cancer screening program between 2007 and 2015 inclusively. The associations between radiologists' and facilities' characteristics and (1) the DCIS detection rate, (2) the invasive detection rate, and (3) the odds of DCIS on invasive detection were assess. For statistically significant associations in the latter analysis, analyses stratified by DCIS grade were performed. Multivariable logistic regression with generalized estimating equations estimates to account for correlation among mammograms was used.

RESULTS

Compared to radiologists with recall rate between 5.0 and 9.9%, radiologists with recall rate between 15.0-19.9% and ≥ 20% reached a higher DCIS detection rate, with adjusted detection ratios of, respectively, 1.33 (95% confidence interval = 1.15-1.53) and 1.43 (95% confidence interval = 1.13-1.81). Increase in radiologist' recall rate was statistically significantly associated with an increase in detection of low/intermediate-grade DCIS (P < 0.001), while not in high-grade DCIS (P = 0.15).

CONCLUSIONS

A major determinant of DCIS detection is the radiologists' recall rate. Abnormalities referred by radiologists with higher recall rates should be identified in order to understand how to decrease recall rate while keeping an optimal DCIS and invasive detection rate.

Effect of the EQUIP initiative on additional images performed at screening mammography: a pilot study

PURPOSE

The Enhancing Quality Using the Inspection Program (EQUIP) initiative was launched to improve clinical image quality. The purpose of this study was to determine if the implementation of the EQUIP reporting system resulted in an increased number of extra views performed at the technologists' discretion during screening mammography.

MATERIALS AND METHODS

Following IRB approval at a single comprehensive cancer center, patients who underwent screening mammography with combination full-field digital mammography plus digital breast tomosynthesis during a 6-month period before (January 2017 to June 2017) and after (January 2018 to June 2018) EQUIP implementation were identified. For each patient, both screening mammograms were retrospectively reviewed by 1 of 3 subspecialized breast radiologists (3-10 years of experience). The following data were recorded: demographics, breast density, surgical history, technologist, number and type of extra views, final BI-RADS assessment, radiologist-assigned indication for the view, and radiologist-assigned necessity of the view. McNemar's test for paired data was computed with p value of <0.05 considered statistically significant.

RESULTS

Of 820 patients, 370 (45%) had additional views in 2018 compared to 317 (39%) in 2017. After EQUIP, patients were 38% more likely to have additional views (OR = 1.38, 95% CI = 1.11-1.73). The total number of additional views in 2018 was 636 compared to 530 in 2017 (20% increase). Among patients with extra views in both years, the number of additional views per patient did not significantly increase post EQUIP implementation (OR = 1.18, 95% CI = 0.73-1.92). The most common extra view was exaggerated craniocaudal lateral, and the most common reason cited by the reviewing radiologist was lateral fibroglandular tissue at the edge of the images. Most of the extra views performed in 2018 were not performed in 2017 and over half were deemed unnecessary. Eight of eleven technologists demonstrated an increased frequency of screening mammograms with extra views performed post EQUIP.

CONCLUSION

Following EQUIP implementation, screening mammography patients were significantly more likely to have extra views performed at the technologists' discretion. Our findings emphasize the importance of ongoing technologist education and radiologist feedback.

Relationship between Mammographic Findings and Breast Abnormalities in a Nigerian Population

PURPOSE

This study aims to describe the mammographic findings in a population of Nigerian women and to explore the relationships between abnormal mammographic findings, breast malignancy, and breast composition.

METHODOLOGY

This was a retrospective study of consecutive mammograms carried out at Union Diagnostics and Clinical Services in Lagos, Nigeria from 2016 to 2018. Demographic information, indications for and findings on mammographic evaluation were obtained. A logistic regression fit model was used to establish the correlation between mammographic findings, breast density, and suspicion for breast malignancy (higher BIRADS scores). P ≤ 0.05 represented a statistically significant result.

RESULTS

A total of 304 patients were involved in this study (age range 20-80 years, mean age 49.0 ± 10.5 years). The patients between 40 and 49 years formed the largest age group with 128 patients (42.4%). Most patients were referred for a breast mass/lump (115/304-38.6%); 56 patients (18.8%) presenting for routine screening. The most common finding on the mammograms was BIRADS 4 in both breasts in 96 patients (31.6%). Most patients had heterogeneous breast density (195 patients - 64.1%). Multivariate logistic regression analysis showed a significant correlation between history of mass, poorly defined margins, and suspicion of malignancy. There was no statistically significant association between abnormal mammographic findings and higher breast density.

CONCLUSION

Poorly defined margins were positively correlated with BIRADS ratings suspicious for malignancy. The presence of a breast mass was positively correlated with a higher BIRADS score when other possible cofounding variables were not accounted for. Patient age did not correlate with breast density in this study.

Massage therapy in the breast imaging department: repurposing an ancient anxiety reducing method

BACKGROUND

Massage therapy's ability to mitigate breast imaging associated anxiety has not been previously studied. Anxiety is, however, often cited as a harm of screening mammography with few options offered to diminish anxiety other than not screening. Reducing anxiety may improve compliance, and reduce breast cancer mortality and morbidity. A complimentary massage therapy program evaluated patient acceptance, anxiety perception and perceived value of massage.

METHODS

Over 10 weeks, verbal agreement was obtained from 113 breast imaging patients who desired a hand or shoulder/neck massage. Licensed massage therapists performed massages before, and/or during, or after, or in between imaging tests. After the massage, questionnaires assessed patients' self-rated perceptions of anxiety before and after massage on a scale from 0 to 10. Participants' age-group, reason for appointment, self-rated value of massage service, and willingness to return to and willingness to refer to the facility were reported. Changes in perceived average anxiety were estimated using a linear mixed effects model. Fisher's exact test was used to evaluate associations among categorical variables.

RESULTS

A significant decrease in perceived anxiety was observed following massage (d = -3.2, p < 0.001). 107/108 (99%) of respondents reported an improved patient experience with massage. 84/106 (79%) reported willingness to pay at least $5 for massage service.

CONCLUSION

Massage therapy improves the patient experience and decreases perceptions of anxiety. It may be associated with improved breast imaging compliance. Patients' willingness to pay for the service may defray some cost of a massage program.

Subject positions in screening mammography and implications for informed choice

OBJECTIVE

Screening mammography has potential benefits as well as harms, but these are not always communicated to women. We therefore explored how women discuss screening mammography, the subject positions made available in their discourse, and the implications of these for informed choice. Design: We conducted 16 individual interviews with women aged 44-72 years who were attenders (n = 11) and non-attenders (n = 5) of screening, and analysed transcripts through Foucauldian Discourse Analysis. Main Outcome Measures: A semi-structured interview guide, informed by literature and researcher expertise, was used to collect data. Results: The women constructed screening mammography as either helpful or potentially harmful. We identified three subject positions-The Responsible Woman (who attends screening), The Irresponsible Woman (who does not attend screening), and the Judicious Woman (who engages in alternate breast health practices). Conclusion: These subject positions have the potential to limit women's choices, constrain shared decision-making with health professionals, and restrict women's engagement in risk-reducing behaviours. An expanded range of options ultimately offers an alternate future in which women's autonomy to control their own bodies is better supported.

Prediction of Cancer Masking in Screening Mammography Using Density and Textural Features

RATIONALE AND OBJECTIVES

High mammographic density reduces the diagnostic accuracy of screening mammography due to masking of tumors, resulting in possible delayed diagnosis and missed cancers. Women with high masking risk could be preselected for alternative screening regimens less susceptible to masking. In this study, various models to predict masking status are presented based on biometric and image-based parameters.

MATERIALS AND METHODS

For a cohort of 67 nonscreen-detected (cancers detected via other means after a negative mammogram) and 147 screen-detected invasive cancers, quantitative volumetric breast density, BI-RADS density, and the distribution and appearance of dense tissue through statistical and texture metrics were measured. Age and Body Mass Index were recorded. Stepwise multivariate logistic regressions were computed to select those parameters that predicted nonscreen-detected cancers. Accuracy of the models was evaluated using the area under receiver operator characteristic curve (AUC).

RESULTS

Using BI-RADS density alone to predict masking risk yielded an AUC of 0.64 (95% confidence interval [0.57-0.70]). Age-adjusted BI-RADS density or volumetric breast density had AUCs of 0.72 [0.64-0.79] and 0.71 [0.62-0.78], respectively. A model extracted from the full pool of variables had an AUC of 0.75 [0.67-0.82].

CONCLUSION

The optimal model predicts masking more accurately than density alone, suggesting that texture metrics may be useful in models to guide a stratified screening strategy.

Overview of Breast Cancer Screening and Diagnosis

Screening mammography saves lives. The mainstay of screening has been mammography. Multiple alternative options, however, for supplemental imaging are now available. Some are just improved anatomic delineation whereas others include physiology added to anatomy. A third group (molecular imaging) is purely physiologic. This article describes and compares the available options and for which patient populations they should be used.

Tumour characteristics of bilateral screen-detected cancers and bilateral interval cancers in women participating at biennial screening mammography

BACKGROUND

Unilateral interval breast cancers show less favourable prognostic features than unilateral screen-detected cancers, but data on tumour characteristics of bilateral interval cancers in a systematically screened population are sparse. Therefore, we compared tumour characteristics of bilateral interval cancers with those of bilateral screen-detected cancers.

METHODS

We included all 468,720 screening mammograms of women who underwent biennial screening mammography in the South of the Netherlands between January 2005 and January 2015. We collected breast imaging reports, biopsy results and surgical reports of all recalled women and of all women who presented with interval breast cancer. In women with synchronous bilateral breast cancer, the tumour with the highest tumour stage was defined as the index cancer. For comparison of data between both groups Fisher exact test and Chi-square test were used.

RESULTS

Synchronous bilateral cancer was diagnosed in 2.2% of screen-detected cancers (64/2947) and in 3.2% of interval cancers (24/753) (P = 0.1). Index tumours of bilateral screen-detected cancers and interval cancers showed similar characteristics, except for a larger proportion of T-stage 2 or worse (T2+) cancers among interval cancers (16/24 (66.7%) versus 23/58 (39.7%) (P = 0.03). Index cancers, compared to contralateral cancers, were less frequently stage T1 in both bilateral screen-detected cancers and bilateral interval cancers (35/64 (60.3%) versus 40/64 (88.9%) (P = 0.001) and 8/24 (33.3%) versus 18/24 (85.7%) (P < 0.001), respectively). In bilateral screen-detected cancers, contralateral cancers were more often stage 1a-c (P < 0.001) compared to index cancers. In bilateral index cancers, index cancers were more often of the lobular subtype (P < 0.001).

CONCLUSION

Index cancers of bilateral screen-detected cancers and bilateral interval cancers show significant differences in tumour size, whereas nodal status, receptor status and final surgical treatment are comparable. In bilateral screen-detected cancer, index cancers had a significantly higher tumour stage. In bilateral screen-detected cancer, index cancers were more often the ductal invasive subtype compared to contralateral cancers.

Breast compression techniques in screening mammography - A Maltese evaluation project

INTRODUCTION

In screening mammography, the radiographer should be responsible for providing mammograms of high diagnostic value, possibly without subjecting clients to a painful experience. This skill is demonstrated via the technique of breast compression and is explored in this study by analysing insights about methods and underlying principles in regards to this procedure.

METHODS

One-to-one semi-structured interviews were conducted with radiographers who perform screening mammography in Malta. For data analysis, a descriptive phenomenological approach following a simplified version of Hycner's (1985) method was adopted.

RESULTS

Five general themes were extracted from the data; meeting the client, preparing the client, the mammography procedure, pain from compression and client turnout. It was determined that the participants alter their breast compression technique according to the client rather than following a rigid step-by-step process and that explanation and requesting client feedback are essential to obtain cooperation. Additionally, mammography positioning and compression application are tailored in a way that encourage compliance, however not at the expense of degrading image quality. Ultimately, it is also believed that a proper breast compression technique positively influences client turnout.

CONCLUSION

The results of this study demonstrate that radiographers should be flexible in their approach in order to carry out a successful breast compression technique. However, it has also been shown that such effectiveness in practice is gained from experience rather than initial training. If exposed to this study's findings, new mammographers would be able to form a robust core of knowledge before embarking on the challenging specialisation of mammography.

Communication Practices of Mammography Facilities and Timely Follow-up of a Screening Mammogram with a BI-RADS 0 Assessment

RATIONALE AND OBJECTIVES

The objective of this study was to evaluate the association of communication practices with timely follow-up of screening mammograms read as Breast Imaging Reporting and Data Systems (BI-RADS) 0 in the Population-based Research Optimizing Screening through Personalized Regimens (PROSPR) consortium.

MATERIALS AND METHODS

A radiology facility survey was conducted in 2015 with responses linked to screening mammograms obtained in 2011-2014. We considered timely follow-up to be within 15 days of the screening mammogram. Generalized estimating equation models were used to evaluate the association between modes of communication with patients and providers and timely follow-up, adjusting for PROSPR site, patient age, and race and ethnicity.

RESULTS

The analysis included 34,680 mammography examinations with a BI-RADS 0 assessment among 28 facilities. Across facilities, 85.6% of examinations had a follow-up within 15 days. Patients in a facility where routine practice was to contact the patient by phone if follow-up imaging was recommended were more likely to have timely follow-up (odds ratio [OR] 4.63, 95% confidence interval [CI] 2.76-7.76), whereas standard use of mail was associated with reduced timely follow-up (OR 0.47, 95% CI 0.30-0.75). Facilities that had standard use of electronic medical records to report the need for follow-up imaging to a provider had less timely follow-up (OR 0.56, 95% CI 0.35-0.90). Facilities that routinely contacted patients by mail if they missed a follow-up imaging visit were more likely to have timely follow-up (OR 1.65, 95% CI 1.02-2.69).

CONCLUSIONS

Our findings support the value of telephone communication to patients in relation to timely follow-up. Future research is needed to evaluate the role of communication in completing the breast cancer screening episode.

Associations of County-level Radiologist and Mammography Facility Supply with Screening Mammography Rates in the United States

RATIONALE AND OBJECTIVES

The present study aims to assess associations of Medicare beneficiary screening mammography rates with local mammography facility and radiologist availability.

MATERIALS AND METHODS

Mammography screening rates for Medicare fee-for-service beneficiaries were obtained for US counties using the County Health Rankings data set. County-level certified mammography facility counts were obtained from the United States Food and Drug Administration. County-level mammogram-interpreting radiologist and breast imaging subspecialist counts were determined using Centers for Medicare & Medicaid Services fee-for-service claims files. Spearman correlations and multivariable linear regressions were performed using counties' facility and radiologist counts, as well as counts normalized to counties' Medicare fee-for-service beneficiary volume and land area.

RESULTS

Across 3035 included counties, average screening mammography rates were 60.5% ± 8.2% (range 26%-88%). Correlations between county-level screening rates and total mammography facilities, facilities per 100,000 square mile county area, total mammography-interpreting radiologists, and mammography-interpreting radiologists per 100,000 county-level Medicare beneficiaries were all weak (r = 0.22-0.26). Correlations between county-level screening rates and mammography rates per 100,000 Medicare beneficiaries, total breast imaging subspecialist radiologists, and breast imaging subspecialist radiologists per 100,000 Medicare beneficiaries were all minimal (r = 0.06-0.16). Multivariable analyses overall demonstrated radiologist supply to have a stronger independent effect than facility supply, although effect sizes remained weak for both.

CONCLUSION

Mammography facility and radiologist supply-side factors are only weakly associated with county-level Medicare beneficiary screening mammography rates, and as such, screening mammography may differ from many other health-care services. Although efforts to enhance facility and radiologist supply may be helpful, initiatives to improve screening mammography rates should focus more on demand-side factors, such as patient education and primary care physician education and access.

Screening mammography among nursing home residents in the United States: Current guidelines and practice

OBJECTIVE

United States (US) guidelines regarding when to stop routine breast cancer screening remain unclear. No national studies to-date have evaluated the use of screening mammography among US long-stay nursing home residents. This cross-sectional study was designed to identify prevalence, predictors, and geographic variation of screening mammography among that population in the context of current US guidelines.

MATERIALS AND METHODS

Screening mammography prevalence, identified with Physician/Supplier Part B claims and stratified by guideline age classification (65-74, ≥75 years), was estimated for all women aged ≥65 years residing in US Medicare- and Medicaid- certified nursing homes (≥1 year) with an annual Minimum Data Set (MDS) 3.0 assessment, continuous Medicare Part B enrollment, and no clinical indication for screening mammography as of 2011 (n = 389,821). The associations between resident- and regional- level factors, and screening mammography, were estimated by crude and adjusted prevalence ratios from robust Poisson regressions clustered by facility.

RESULTS

Women on average were 85.4 (standard deviation ±8.1) years old, 77.9% were disabled, and 76.3% cognitively impaired. Screening mammography prevalence was 7.1% among those aged 65-74 years (95% Confidence Interval (CI): 6.8%-7.3%) and 1.7% among those ≥75 years (95% CI, 1.7%-1.8%), with geographic variation observed. Predictors of screening in both age groups included race, cognitive impairment, frailty, hospice, and some comorbidities.

CONCLUSIONS

These results shed light on the current screening mammography practices in US nursing homes. Thoughtful consideration about individual screening recommendations and the implementation of more clear guidelines for this special population are warranted to prevent overscreening.

Non-communicable chronic diseases and timely breast cancer screening among women of the Eastern Caribbean Health Outcomes Research Network (ECHORN) Cohort Study

PURPOSE

The Caribbean population faces a growing burden of multiple non-communicable chronic diseases (NCDs). Breast cancer is the leading cause of cancer death for women in the Caribbean. Given the substantial burden of NCDs across the region, cancer prevention and control strategies may need to be specifically tailored for people with multiple co-morbidities. Preventive screening, such as timely mammography, is essential but may be either facilitated or hampered by chronic disease control. The main objective of this study is to examine the relationship between a chronic disease and timely breast cancer screening.

METHODS

We conducted a cross-sectional data analysis using baseline data from the Eastern Caribbean Health Outcomes Research Network (ECHORN) Cohort Study-ECS. Our independent variables were presence of chronic diseases (hypertension or diabetes), defined as having been told by a clinical provider. Our dependent variable was timely screening mammography, as defined by receipt of mammography within the past 2 years. We examined bivariate and multivariate associations of covariates and timely screening mammography.

RESULTS

In our sample (n = 841), 52% reported timely screening mammography. Among those with timely screening, 50.8% reported having hypertension, and 22.3% reported having diabetes. In our bivariate analyses, both diabetes and hypertension were associated with timely screening mammography. In partially adjusted models, we found that women with diabetes were significantly more likely to report timely screening mammography than women without diabetes. In our fully adjusted models, the association was no longer significant. Having a usual source of healthcare and a woman's island of residence were significantly associated with timely screening mammography (p < 0.05).

CONCLUSIONS

We found that half of eligible women received timely screening mammography. Diabetes and hypertension, though common, are not associated with timely screening mammography. Usual source of care remains an important factor to timely breast cancer screening.

Performance Goals for an Adjunct Diagnostic Test to Reduce Unnecessary Biopsies After Screening Mammography: Analysis of Costs, Benefits, and Consequences

PURPOSE

Because benign biopsies resulting from false-positive mammographic findings are a known harm of breast cancer screening, physicians and test manufacturers are searching for ways to reduce their frequency. The aim of this study was to estimate potential costs and consequences associated with using an adjunct diagnostic test for triaging women with suspicious mammographic findings before biopsy.

METHODS

A decision model was developed to compare the use of an adjunct test before biopsy to the current standard of care for suspicious mammographic findings. The decision analysis was performed from the perspective of a national health payer, with a 1-year time horizon among women representative of the US screening population aged 40 to 79 years. Three primary outcomes were assessed: (1) incremental costs, (2) number of benign biopsies avoided, and (3) number of missed opportunities for diagnosing cancer per million women screened. Input parameters were obtained from the medical literature and expert opinion. Sensitivity analyses were performed to evaluate the effects of uncertainty in parameter estimates.

RESULTS

The base-case analysis demonstrated that the use of an adjunct diagnostic test with 95% sensitivity, 75% specificity, and a cost of $1,000 would eliminate 8,127 unnecessary breast biopsies per million women screened. However, this would cost the US health care system an additional $6,462,977 and result in 255 missed opportunities for diagnosing cancer per million women screened.

CONCLUSIONS

The addition of an adjunct test for triaging women for breast biopsy after abnormal findings on screening mammography would likely eliminate many unnecessary biopsies but also increase overall health care costs. This exploratory analysis highlights the fact that mammography remains a relatively inexpensive and effective breast cancer screening and diagnostic modality.

Incidence and tumour characteristics of bilateral and unilateral interval breast cancers at screening mammography

BACKGROUND

Detected by screening mammography, bilateral breast cancer has a different pathological profile compared to unilateral breast cancer. We investigated the incidence of bilateral interval breast cancers and compared their characteristics with those of unilateral interval breast cancers.

METHODS

We included all 468,720 screening mammograms of women who underwent biennial screening mammography in the South of the Netherlands between January 2005 and January 2015. We collected breast imaging reports, biopsy results and surgical reports of all referred women and of all women who presented with interval breast cancer. The tumour with the highest tumour stage (index cancer) was used for comparison with unilateral interval cancers.

RESULTS

A total of 753 interval cancers were detected, of which 24 (3.2%) were bilateral. Among the invasive interval cancers, bilateral cancers more frequently showed a lobular histology than unilateral cancers (37.5% (9/24) vs. 16.1% (111/691), P = .01). There is a trend towards a larger proportion of bilateral than unilateral interval cancers graded 1 (45.8% (11/24) vs. 27.8% (192/691), P = .08). There were no other statistically significant differences in tumour characteristics. Also, the proportion of interval cancers showing significant mammographic abnormalities at the latest screen was comparable for unilateral and bilateral interval cancers (23.0% vs. 25.0%, P = .9).

DISCUSSION

Bilateral interval cancers comprise a small proportion of all interval cancers. Except of a higher proportion of invasive lobular cancers and a more favourable histological grade of invasive cancers, tumour characteristics are comparable for bilateral and unilateral interval breast cancers.

The Challenges of Screening Mammography in Racial/Ethnic Minority Populations in the United States: A mini-review and observations from a predominantly Hispanic community

Screening mammography is recommended by U.S. medical organizations for breast cancer screening in average risk women because of its demonstrated reductions in breast cancer mortality. However, significant disparities in breast cancer screening utilization and mortality remain among racial/ethnic minorities. Efforts have appropriately been directed at increasing engagement with screening services in these populations, however, there is a dearth of data regarding false-positive rates and overdiagnosis in minority patients engaged in breast cancer screening. We recently examined screening practices among a predominantly Hispanic population presenting to an academic medical center in New York, NY, and found that approximately 53% of women experienced at least one false-positive mammography result over a median of 8.9 years of screening. We also observed that Hispanic women were more likely to screen annually than white women despite recommendations to screen less frequently. In this review, we briefly review the benefits and harms of screening mammography in average-risk women, namely, false-positive results and breast cancer overdiagnosis, followed by a discussion of the disparities in breast cancer screening and mortality among racial/ethnic minority populations. We then present our own recent observations and propose that future interventions among Hispanic and other minority populations could include patient- and provider-centered educational programs that focus on providing a balanced discussion of benefits and harms of screening mammography.

Breast cancer screening utilization among women from Muslim majority countries in Ontario, Canada

Breast cancer screening disparities continue to prevail with immigrant women being at the forefront of the under screened population. There is a paucity of knowledge about the role of religious affiliation or cultural orientation on immigrant women's cancer screening uptake. This study examined differences in uptake of breast cancer screening among women from Muslim and non- Muslim majority countries in Ontario, Canada. A cohort of 1,851,834 screening-eligible women living in Ontario during April 1, 2013 to March 31, 2015 was created using linked health and social administrative databases. The study found that being born in a Muslim majority country was associated with lower breast cancer screening uptake after adjusting for region of origin, neighbourhood income, and primary care-related factors. However, screening uptake in Muslim majority countries varied by world region with the greatest differences found in Sub-Saharan Africa and South Asia. Screening uptake was lower for women who had no primary care provider, were in a traditional fee-for service model of primary care, had a male physician, had an internationally trained physician, resided in a low income neighbourhood, and entered Canada under the family class of immigration. Religion may play a role in screening uptake, however, the variation in rates by regions of origin, immigration class, and access to primary care providers alludes to confluence of socio-demographic, cultural beliefs and practices, immigration trajectories and system level factors. Facilitating access for immigrant women to regular primary care providers, particularly female providers and enrollment in primary care models could enhance screening uptake.

Effect of exposure factors on image quality in screening mammography

INTRODUCTION

The aim of this research was to study the effect of exposure factors on image quality for digital screening mammography units in Kuwait which use Tungsten (W) targets with Rhodium (Rh) and Silver (Ag) as filters.

METHODS

Mammography Accreditation Phantom Model 015 was imaged using a Hologic Selenia Digital mammography unit with W targets and Rh and Ag filters. Four images, each at 26, 28, 30, and 32 kVp, were obtained using each target-filter combination (W/Rh and W/Ag). The images were evaluated by five senior technologists for the number of specks, fibers and masses visible on each image. Statistical analysis was carried out using non-parametric tests at p = 0.05 level.

RESULTS

There were significant changes in the visibility of fibers and specks between different kVp values with W/Rh (p < 0.001). However, with W/Ag combination, significant differences were observed in the fibers only (p < 0.001). Among the kVp values used, 28 kV emerged as the optimal value. Comparison of images obtained with the two filter materials, led to significant differences in the visibility of fibers and specks (p < 0.008). At 32 kVp, there were significant differences in the visibility of specks only (p < 0.008).

CONCLUSION

A W/Rh target-filter combination provides better image quality than that provided by W/Ag. In particular, 30 and 32 kVp X-ray beams produce higher quality images than the lower kV values.

Correlation Between Screening Mammography Interpretive Performance on a Test Set and Performance in Clinical Practice

RATIONALE AND OBJECTIVES

Evidence is inconsistent about whether radiologists' interpretive performance on a screening mammography test set reflects their performance in clinical practice. This study aimed to estimate the correlation between test set and clinical performance and determine if the correlation is influenced by cancer prevalence or lesion difficulty in the test set.

MATERIALS AND METHODS

This institutional review board-approved study randomized 83 radiologists from six Breast Cancer Surveillance Consortium registries to assess one of four test sets of 109 screening mammograms each; 48 radiologists completed a fifth test set of 110 mammograms 2 years later. Test sets differed in number of cancer cases and difficulty of lesion detection. Test set sensitivity and specificity were estimated using woman-level and breast-level recall with cancer status and expert opinion as gold standards. Clinical performance was estimated using women-level recall with cancer status as the gold standard. Spearman rank correlations between test set and clinical performance with 95% confidence intervals (CI) were estimated.

RESULTS

For test sets with fewer cancers (N = 15) that were more difficult to detect, correlations were weak to moderate for sensitivity (woman level = 0.46, 95% CI = 0.16, 0.69; breast level = 0.35, 95% CI = 0.03, 0.61) and weak for specificity (0.24, 95% CI = 0.01, 0.45) relative to expert recall. Correlations for test sets with more cancers (N = 30) were close to 0 and not statistically significant.

CONCLUSIONS

Correlations between screening performance on a test set and performance in clinical practice are not strong. Test set performance more accurately reflects performance in clinical practice if cancer prevalence is low and lesions are challenging to detect.

Analysis of Participant Factors That Affect the Diagnostic Performance of Screening Mammography: A Report of the Alliance for Breast Cancer Screening in Korea

OBJECTIVE

To analyze participant factors that affect the diagnostic performance of screening mammography.

MATERIALS AND METHODS

We enrolled 128756 cases from 10 hospitals between 2005 and 2010. We analyzed recall rate, cancer detection rate (CDR) per 1000 examinations, positive predictive value (PPV), sensitivity, specificity, false positive rate (FPR), and interval cancer rate (ICR) per 1000 negative examinations according to participant factors including age, breast density, and number of visit to the same institution, and adjusted for confounding variables.

RESULTS

Increasing age improved recall rates (27.4% in 40's, 17.5% in 50's, 11.1% in 60's, and 8.6% in 70's), CDR (2.7, 3.2, 2.0, and 2.4), PPV (1.0, 1.8, 1.8, and 2.8%), sensitivity (81.3, 88.8, 90.3, and 94.7%), specificity (72.7, 82.7, 89.0, and 91.7%), and FPR (27.3, 17.3, 11.0, and 8.4%) (p < 0.05). Higher breast density impaired recall rates (4.0% in P1, 9.0% in P2, 28.9% in P3, and 27.8% in P4), PPV (3.3, 2.3, 1.2, and 1.3%), specificity (96.1, 91.2, 71.4, and 72.5%), and FPR (3.9, 8.9, 28.6, and 27.6%) (p < 0.001). It also increased CDR (1.3, 2.1, 3.3, and 3.6) and ICR (0.2, 0.3, 0.6, and 1.6) (p < 0.05). Successive visits to the same institution improved recall rates (20.9% for one visit, 10.7% for two visits, 7.7% for more than three visits), PPV (1.6, 2.8, and 2.7%), specificity (79.4, 89.6, and 92.5%), and FPR (20.6, 10.4, and 7.5%) (p < 0.001).

CONCLUSION

Young age and dense breasts negatively affected diagnostic performance in mammography screening, whereas successive visits to the same institution had a positive effect. Examinee education for successive visits to the same institution would improve the diagnostic performance.

Differential Use of Screening Mammography in Older Women Initiating Metformin versus Sulfonylurea

PURPOSE

Differential use of screening mammography may lead to biased detection of breast cancer. This study aimed to compare receipt of screening mammography and the incidence of screen-detected breast cancer between metformin and sulfonylurea initiators.

METHODS

We used 2006-2014 US Medicare claims to identify initiators of metformin or sulfonylurea aged 65+ years continuously enrolled in Parts A/B for ≥2 years pre-initiation and ≥2 years post-initiation. We reported frequencies of screening mammograms and screen-detected breast cancer in 1 year pre-initiation among all cohort members and in 1 year post-initiation among cancer-free cohort members. Weighted screening risk differences (RDs) were estimated comparing metformin to sulfonylurea group.

RESULTS

We identified 41,436 and 13,367 initiators of metformin and sulfonylurea, 35% and 24% of which had ≥1 screening mammogram in 1 year pre-initiation (weighted RD: 6 percentage points; 95% CI: 5 to 7), respectively. The weighted RD for screen-detected breast cancer associated with metformin was 0.00 percentage points (95% CI: -0.09 to 0.09). Among cancer-free cohort members, metformin initiators had 5 percentage points (95% CI: 4 to 6) and 0.11 percentage points (95% CI: -0.02 to 0.23) absolute risk excess of screening mammography and screen-detected breast cancer in 1 year post-initiation, compared with sulfonylurea initiators, respectively.

CONCLUSIONS

Metformin initiators were more likely to receive screening mammograms than sulfonylurea initiators pre- and post-initiation, indicating possible detection bias due to differential screening mammography. Researchers should be aware of the potential for more screening mammograms pre- and post-initiation when interpreting the findings of metformin on breast cancer incidence. Copyright © 2017 John Wiley & Sons, Ltd.

Breast Cancer Screening in Patients With Newly Diagnosed Lung and Colorectal Cancer: A Population-Based Study of Utilization

PURPOSE

To assess breast cancer screening utilization in Medicare beneficiaries with colorectal and lung cancer versus cancer-free controls.

METHODS

Female fee-for-service Medicare beneficiaries who were ≥67 years old and diagnosed with lung or colorectal cancer between 2000 and 2011 and who reported to a Surveillance, Epidemiology, and End Results (SEER) registry (case group) were followed for 2 years after their diagnoses, unless death, a diagnosis of breast cancer, or the end of 2013 came first. A similar number of cancer-free controls were individually matched to cases by age, race, registry region, and follow-up time. Screening utilization was defined as the percentage of women with ≥1 screening mammogram during follow-up.

RESULTS

Overall, 104,164 cases (48% colorectal, 52% lung; 30% advanced cancer) and 104,164 controls were included. Among women with lung or colorectal cancer, 22% underwent ≥1 screening mammogram versus 26% of controls (odds ratio [OR] 0.80; 95% confidence interval [CI] 0.78-0.82). Stratified by cancer type, 28% of colorectal cancer cases versus 29% of controls (OR 0.98; 95% CI 0.95-1.01) and 17% of lung cancer cases versus 23% of controls (OR 0.63; 95% CI 0.60-0.65) received ≥1 mammogram. When stratified by stage, 8% with advanced cancer versus 18% of controls (OR 0.33; 95% CI 0.31-0.35) and 30% with early-stage cancer versus 30% of controls (OR 1; 95% CI 0.97-1.02) underwent ≥1 mammogram.

CONCLUSION

Screening mammography utilization rates are similar between Medicare beneficiaries with early-stage cancer versus controls. Although the majority of patients with advanced-stage cancer appropriately do not pursue screening mammography, a small number (8%) continue with screening.

Audit of mammography requests in Abakaliki, South-East Nigeria

BACKGROUND

Breast cancer is the leading cancer in women in both developed and developing countries. Screening mammography detects breast cancer even before a lump can be palpated, with better prognosis. The introduction of mammographic technique for screening breast cancer, despite its importance, has been slow to adopt and virtually non-existent in many parts of Sub-Saharan Africa including Nigeria. For this reason, the indications of mammography have not been well defined in our setting. The aim of this study was to audit our mammography requests, with a view to improving its application in our setting.

METHODS

This is a descriptive study carried out on 69 female patients who had mammography at the National Obstetric Fistula Centre, Abakaliki, from January 2014 to December 2015. Findings on clinical examination were entered in a proforma. Mammography was performed in craniocaudal and mediolateral views using the Lorad M-IV (film-screen) mammography machine. Data was analysed using the Statistical Package for Social Sciences (SPSS) version 21.

RESULTS

All 69 patients were females. Their mean age was 42.1 ± 11 years. Majority of the patients (69.6%) were between 30 and 49 years. The commonest indication for mammography was breast lump which was found in 46 patients (66.7%). Breast pain was present in 36 (52.2%) of patients. The different Breast Imaging Reporting and Data System (BIRADS) categories were BIRADS 0: 20 (28.99%), BIRADS 1: 8 (11.59%), BIRADS 2: 9 (13.04%), BIRADS 3: 4 (5.8%), BIRADS 4: 19 (27.54%) and BIRADS 5: 9 (13.04%).

CONCLUSIONS

Diagnostic mammography remains the commonest indication for mammography in our setting. Public awareness, poverty reduction and ready availability of mammography facilities are required to improve screening mammography in our setting.

Direct Interactive Public Education by Breast Radiologists About Screening Mammography: Impact on Anxiety and Empowerment

PURPOSE

Anxiety has been called a "harm" of screening mammography. The authors provided direct, interactive education to lay audiences and measured these sessions' impact on anxiety and any increased understanding of breast cancer screening.

METHODS

Academic breast radiologist provided seven 1-hour sessions of structured lectures and question-and-answer periods. Lay language and radiologic images were used to discuss disease background, screening guidelines, and areas of debate. One hundred seventeen participants (mean age, 45 ± 15 years) completed voluntary, anonymous, institutional review board-approved pre and postsession questionnaires relaying their attitudes regarding screening and the impact of the sessions. Results are summarized descriptively.

RESULTS

Mean reported anxiety regarding screening (on a scale ranging from 1-5; 1 = no anxiety) was 2.5 ± 1.3. Anxiety was attributed to unknown results (56.4%), anticipation of pain (21.8%), known risk factors (14.5%), general uncertainty (12.7%), waiting for results (9.1%), possibility of more procedures (3.6%), and personal breast cancer history (3.6%). Ninety-seven percent reported that immediate results would lower anxiety (78% of those women indicated a 75%-100% decrease in anxiety); 93% reported that radiologist consultation with images would lower anxiety (75.6% indicated a 75%-100% decrease in anxiety). After the lecture, women reported (on a scale ranging from 1-5) increased understanding of the topic (4.7 ± 0.6), encouragement to screen (4.6 ± 0.7), and reduced anxiety (4.0 ± 1.1). Ninety-seven percent to 100% provided correct responses to these questions: rationale for screening in the absence of family history, recall does not equate to cancer diagnosis, benefit of prior films, and continued importance of physical examination.

CONCLUSION

Attendees of radiologist-provided direct public lectures reported decreased anxiety and improved knowledge regarding screening mammography. The resultant reduced anxiety ("harm") and educational empowerment help enable informed decision making and may promote screening attendance.

A Simulation Screening Mammography Module Created for Instruction and Assessment: Radiology Residents vs National Benchmarks

RATIONALE AND OBJECTIVES

To improve mammographic screening training and breast cancer detection, radiology residents participated in a simulation screening mammography module in which they interpreted an enriched set of screening mammograms with known outcomes. This pilot research study evaluates the effectiveness of the simulation module while tracking the progress, efficiency, and accuracy of radiology resident interpretations and also compares their performance against national benchmarks.

MATERIALS AND METHODS

A simulation module was created with 266 digital screening mammograms enriched with high-risk breast lesions (seven cases) and breast malignancies (65 cases). Over a period of 27 months, 39 radiology residents participated in the simulation screening mammography module. Resident sensitivity and specificity were compared to Breast Cancer Surveillance Consortium (BCSC data through 2009) national benchmark and American College of Radiology (ACR) Breast Imaging Reporting and Data System (BI-RADS) acceptable screening mammography audit ranges.

RESULTS

The sensitivity, the percentage of cancers with an abnormal initial interpretation (BI-RADS 0), among residents was 84.5%, similar to the BCSC benchmark sensitivity of 84.9% (sensitivity for tissue diagnosis of cancer within 1 year following the initial examination) and within the acceptable ACR BI-RADS medical audit range of ≥75%. The specificity, the percentage of noncancers that had a negative image interpretation (BI-RADS 1 or 2), among residents was 83.2% compared to 90.3% reported in the BCSC benchmark data, but lower than the suggested ACR BI-RADS range of 88%-95%.

CONCLUSIONS

Using simulation modules for interpretation of screening mammograms is a promising method for training radiology residents to detect breast cancer and to help them achieve competence toward national benchmarks.

Utilization of screening mammography in older women according to comorbidity and age: protocol for a systematic review

BACKGROUND

Approximately half of new invasive breast cancer cases diagnosed each year in the United States occur among women aged 65 years and older. The increasing life expectancy coupled with the attendant rise in breast cancer incidence and elimination of out-of-pocket expenses for screening mammography as a result of the Affordable Care Act could lead to higher utilization rates of screening mammography. Although research indicates that life expectancy should be a strong consideration when making screening decisions among older women, the extent to which screening mammography utilization is tailored to comorbidity and life expectancy is not well established.

METHODS/DESIGN

To identify relevant studies, a systematic search of the literature will be conducted using PubMed and EMBASE between January 1, 1991, and March 1, 2016. Additional studies will be found through citation review or by contacting experts in the field. The inclusion criteria will be any study design comprised of women aged 65 and older, assessing women's comorbidity, functional impairments, and/or health status, and reporting outcome measures that addressed mammography utilization within the last 1-5 years. For each study, two authors will independently abstract data regarding study eligibility and outcomes to determine relevance. Quantitative results will be extracted from text and tables, choosing preferably those adjusted for important confounders.

DISCUSSION

The review will provide evidence on the impact of comorbidity, functional limitations, and health status on screening mammography utilization in older women and inform decision aids in this area.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016032661.

Radiologists' interpretive skills in screening vs. diagnostic mammography: are they related?

PURPOSE

This study aims to determine whether radiologists who perform well in screening also perform well in interpreting diagnostic mammography.

MATERIALS AND METHODS

We evaluated the accuracy of 468 radiologists interpreting 2,234,947 screening and 196,164 diagnostic mammograms. Adjusting for site, radiologist, and patient characteristics, we identified radiologists with performance in the highest tertile and compared to those with lower performance.

RESULTS

A moderate correlation was noted for radiologists' accuracy when interpreting screening versus their accuracy on diagnostic examinations: sensitivity (r_spearman=0.51, 95% CI: 0.22, 0.80; P=.0006) and specificity (r_spearman=0.40, 95% CI: 0.30, 0.49; P<.0001).

CONCLUSION

Different educational approaches to screening and diagnostic imaging should be considered.

Compliance With Screening Mammography Guidelines After a False-Positive Mammogram

PURPOSE

To assess whether women with a false-positive mammogram who do return for screening are less likely to be compliant with screening mammography guidelines than are women with a negative mammogram.

METHODS

This institutional review board-approved, HIPAA-compliant retrospective cohort study includes women >40 years old who received 9,385 consecutive, nonbaseline screening mammograms between December 1, 2012 and December 31, 2013. Using linear regression, we evaluated differences in time between mammograms by prior recall status, after adjusting for location of current mammogram (outpatient office versus mobile unit) and age. Using Fisher's exact test, we evaluated the association between compliance with screening guidelines and the recall status on prior mammogram, and compared by location the proportions of noncompliant women who were recalled from prior mammogram.

RESULTS

Time between mammograms does not differ based on prior recall status (P = .83). There is no association between compliance with screening mammography guidelines and recall status on prior mammogram (ACR guidelines P = .398, United States Preventive Services Task Force guidelines P = .416). Noncompliant women recalled on prior mammogram are more likely to undergo mammography at the outpatient office rather than the mobile unit (ACR guidelines P = .0004, United States Preventive Services Task Force guidelines P = .0032).

CONCLUSIONS

A prior false-positive mammogram is not a significant deterrent to compliance with screening guidelines in those women who return for screening.

Comparative safety of diabetes medications and risk of incident invasive breast cancer: a population-based cohort study

PURPOSE

Growing evidence suggests that certain commonly used diabetes medications have the potential to differentially alter breast cancer risk. We evaluated the influence of metformin, insulin, and sulfonylureas on risk of incident invasive breast cancer.

METHODS

We conducted a retrospective cohort study of women ≥40 years of age enrolled in a health plan between 1996 and 2011. Ever, current (≤12 months), and duration (<1, 1-2.9, ≥3 years) of diabetes medication use were obtained from pharmacy databases and modeled as time varying. Multivariable Cox proportional hazards models adjusting for potential confounders including screening mammography and body mass index were used to estimate hazard ratios (HRs) and 95% Confidence Intervals (CIs).

RESULTS

Among 10,050 women with diabetes, 57 % used metformin, 43 % used sulfonylureas, 32 % used insulin, and 301 were diagnosed with breast cancer over median follow-up of 6.7 years. Results suggested no significant decreased risk of breast cancer among metformin users (HR 0.86; 95% CI 0.65-1.12). We found no association between increased breast cancer risk and long-acting insulin (HR 0.95; 95% CI 0.51-1.77), but reduced risk with short-/rapid-acting insulin (HR 0.69; 95% CI 0.50-0.94), and suggestion of a dose-response with increasing duration of short-/rapid-acting insulin use (HR 0.87; 95% CI 0.76-1.00). Estimates for sulfonylurea users suggested increased risk with ever use (HR 1.18; 95% CI 0.90-1.53) and with longer durations of use (≥3 years: HR 1.23; 95% CI 0.88-1.73), but confidence intervals included 1.0.

CONCLUSIONS

Our results provide little support for the previously hypothesized decreased risk of breast cancer with metformin use or for an increased risk with insulin use. Implications for possible residual confounding by screening mammography and comorbidity should be considered in breast cancer pharmacoepidemiology studies.