Impact of Breast Density Legislation on Breast Cancer Risk Assessment and Supplemental Screening: A Survey of 110 Radiology Facilities.

Breast density notification laws, passed in 19 states as of October 2014, mandate that patients be informed of their breast density. The purpose of this study is to assess the impact of this legislation on radiology practices, including performance of breast cancer risk assessment and supplemental screening studies. A 20-question anonymous web-based survey was emailed to radiologists in the Society of Breast Imaging between August 2013 and March 2014. Statistical analysis was performed using Fisher's exact test. Around 121 radiologists from 110 facilities in 34 USA states and 1 Canadian site responded. About 50% (55/110) of facilities had breast density legislation, 36% of facilities (39/109) performed breast cancer risk assessment (one facility did not respond). Risk assessment was performed as a new task in response to density legislation in 40% (6/15) of facilities in states with notification laws. However, there was no significant difference in performing risk assessment between facilities in states with a law and those without (p < 0.831). In anticipation of breast density legislation, 33% (16/48), 6% (3/48), and 6% (3/48) of facilities in states with laws implemented handheld whole breast ultrasound (WBUS), automated WBUS, and tomosynthesis, respectively. The ratio of facilities offering handheld WBUS was significantly higher in states with a law than in states without (p < 0.001). In response to breast density legislation, more than 33% of facilities are offering supplemental screening with WBUS and tomosynthesis, and many are performing formal risk assessment for determining patient management.

Supplemental Breast Cancer Screening With Molecular Breast Imaging for Women With Dense Breast Tissue.

OBJECTIVE: Molecular breast imaging was implemented in routine clinical practice at a large community-based breast imaging center. The aim of this study was to retrospectively assess the clinical performance of molecular breast imaging as a supplementary screening tool for women with dense breast tissue. MATERIALS AND METHODS: Women with dense breasts and negative mammography results who subsequently underwent screening with 300 MBq (8 mCi) (99m)Tc-sestamibi molecular breast imaging were retrospectively analyzed. Outcome measures included cancer detection rate, recall rate, biopsy rate, and positive predictive values (PPVs). RESULTS: Molecular breast imaging screening of 1696 women in this study resulted in the detection of 13 mammographically occult malignancies, of which 11 were invasive, one was node positive, and one had unknown node positivity. The lesion size ranged from 0.6 to 2.4 cm, with a mean of 1.1 cm. The incremental cancer detection rate was 7.7‰ (95% CI, 4.5-13.1‰), the recall rate was 8.4% (95% CI, 7.2-9.8%), and the biopsy rate was 3.7% (95% CI, 2.9%-4.7%). The PPV for recall (PPV 1) was 9.1% (95% CI, 5.4-15.0%), and the PPV for biopsy (PPV 3) was 19.4% (95% CI, 11.4-30.9%). CONCLUSION: When incorporated into a community-based clinical practice environment, molecular breast imaging yielded a high incremental cancer detection rate of 7.7‰ at an acceptable radiation dose. These results show the utility of molecular breast imaging as a supplementary screening tool to mammography for women with dense breasts.

The California breast density information group: a collaborative response to the issues of breast density, breast cancer risk, and breast density notification legislation.

In anticipation of breast density notification legislation in the state of California, which would require notification of women with heterogeneously and extremely dense breast tissue, a working group of breast imagers and breast cancer risk specialists was formed to provide a common response framework. The California Breast Density Information Group identified key elements and implications of the law, researching scientific evidence needed to develop a robust response. In particular, issues of risk associated with dense breast tissue, masking of cancers by dense tissue on mammograms, and the efficacy, benefits, and harms of supplementary screening tests were studied and consensus reached. National guidelines and peer-reviewed published literature were used to recommend that women with dense breast tissue at screening mammography follow supplemental screening guidelines based on breast cancer risk assessment. The goal of developing educational materials for referring clinicians and patients was reached with the construction of an easily accessible Web site that contains information about breast density, breast cancer risk assessment, and supplementary imaging. This multi-institutional, multidisciplinary approach may be useful for organizations to frame responses as similar legislation is passed across the United States. Online supplemental material is available for this article.

Evaluation of breast silicone implants.

While clinical evaluation of breast implants and their complications can identify capsule contracture and rupture of saline implants, the identification of silicone implant failure is best accomplished by silicone specific protocols for MRI with orthogonal acquisition. Such imaging can also help resolve other clinical problems. Following a brief overview of the history and development of commercial use of silicone implants and alternatives, this article outlines the approach toward optimal imaging and expected results.

Benefit of semiannual ipsilateral mammographic surveillance following breast conservation therapy.

PURPOSE: To compare cancer recurrence outcomes on the basis of compliant semiannual versus noncompliant annual ipsilateral mammographic surveillance following breast conservation therapy (BCT). MATERIALS AND METHODS: A HIPAA-compliant retrospective review was performed of post-BCT examinations from 1997 through 2008 by using a deidentified database. The Committee on Human Research did not require institutional review board approval for this study, which was considered quality assurance. Groups were classified according to compliance with institutional post-BCT protocol, which recommends semiannual mammographic examinations of the ipsilateral breast for 5 years. A compliant semiannual examination was defined as an examination with an interval of 0-9 months, although no examination had intervals less than 3 months. A noncompliant annual examination was defined as an examination with an interval of 9-18 months. Cancer recurrence outcomes were compared on the basis of the last examination interval leading to diagnosis. RESULTS: Initially, a total of 10 750 post-BCT examinations among 2329 asymptomatic patients were identified. Excluding initial mammographic follow-up, there were 8234 examinations. Of these, 7169 examinations were semiannual with 94 recurrences detected and 1065 examinations were annual with 15 recurrences detected. There were no differences in demographic risk factors or biopsy rates. Recurrences identified at semiannual intervals were significantly less advanced than those identified at annual intervals (stage I vs stage II, P = .04; stage 0 + stage I vs stage II, P = .03). Nonsignificant findings associated with semiannual versus annual intervals included smaller tumor size (mean, 11.7 vs 15.3 mm; P = .15) and node negativity (98% vs 91%, P = .28). CONCLUSION: Results suggest that a semiannual interval is preferable for ipsilateral mammographic surveillance, allowing detection of a significantly higher proportion of cancer recurrences at an earlier stage than noncompliant annual surveillance.

Are radiologists' goals for mammography accuracy consistent with published recommendations?

RATIONALE AND OBJECTIVES: Mammography quality assurance programs have been in place for more than a decade. We studied radiologists' self-reported performance goals for accuracy in screening mammography and compared them to published recommendations. MATERIALS AND METHODS: A mailed survey of radiologists at mammography registries in seven states within the Breast Cancer Surveillance Consortium (BCSC) assessed radiologists' performance goals for interpreting screening mammograms. Self-reported goals were compared to published American College of Radiology (ACR) recommended desirable ranges for recall rate, false-positive rate, positive predictive value of biopsy recommendation (PPV2), and cancer detection rate. Radiologists' goals for interpretive accuracy within desirable range were evaluated for associations with their demographic characteristics, clinical experience, and receipt of audit reports. RESULTS: The survey response rate was 71% (257 of 364 radiologists). The percentage of radiologists reporting goals within desirable ranges was 79% for recall rate, 22% for false-positive rate, 39% for PPV2, and 61% for cancer detection rate. The range of reported goals was 0%-100% for false-positive rate and PPV2. Primary academic affiliation, receiving more hours of breast imaging continuing medical education, and receiving audit reports at least annually were associated with desirable PPV2 goals. Radiologists reporting desirable cancer detection rate goals were more likely to have interpreted mammograms for 10 or more years, and >1000 mammograms per year. CONCLUSION: Many radiologists report goals for their accuracy when interpreting screening mammograms that fall outside of published desirable benchmarks, particularly for false-positive rate and PPV2, indicating an opportunity for education.

Malignant seeding following percutaneous breast biopsy: documentation with comprehensive imaging and clinical implications.

The aim of this study was to demonstrate convincing evidence that percutaneous breast biopsy may result in displacement of malignant cells that can initiate tumor growth at a separate anatomic site, other than the index lesion. Two patients with malignancy diagnosed by percutaneous breast biopsy were followed up with subsequent imaging. The observation of displaced cells initiating subsequent malignant growth was compared retrospectively with the previous year's outcomes following percutaneous breast biopsy. Two cases of displaced malignant cells resulting in malignant growth at a separate site along the biopsy needle track were demonstrated by imaging. During the preceding year, 1644 biopsies with 298 malignant results were compared with the outcomes of these two patients, resulting in a 0.7% incidence of malignant seeding. No identifiable factors could be identified to predict under what conditions this iatrogenic complication occurs. Although uncommon, percutaneous breast biopsy can result in malignant seeding, and raises issues regarding informed consent and proper subsequent treatment.

Timeliness of follow-up after abnormal screening mammogram: variability of facilities.

PURPOSE: To describe the timeliness of follow-up care in community-based settings among women who receive a recommendation for immediate follow-up during the screening mammography process and how follow-up timeliness varies according to facility and facility-level characteristics. MATERIALS AND METHODS: This was an institutional review board-approved and HIPAA-compliant study. Screening mammograms obtained from 1996 to 2007 in women 40-80 years old in the Breast Cancer Surveillance Consortium were examined. Inclusion criteria were a recommendation for immediate follow-up at screening, or subsequent imaging, and observed follow-up within 180 days of the recommendation. Recommendations for additional imaging (AI) and biopsy or surgical consultation (BSC) were analyzed separately. The distribution of time to follow-up care was estimated by using the Kaplan-Meier estimator. RESULTS: Data were available on 214,897 AI recommendations from 118 facilities and 35,622 BSC recommendations from 101 facilities. The median time to subsequent follow-up care after recommendation was 14 days for AI and 16 days for BSC. Approximately 90% of AI follow-up and 81% of BSC follow-up occurred within 30 days. Facilities with higher recall rates tended to have longer AI follow-up times (P < .001). Over the study period, BSC follow-up rates at 15 and 30 days improved (P < .001). Follow-up times varied substantially across facilities. Timely follow-up was associated with larger volumes of the recommended procedures but not notably associated with facility type nor observed facility-level characteristics. CONCLUSION: Most patients with follow-up returned within 3 weeks of the recommendation.

On the more insidious manifestations of bias in scientific reporting.

Although bias in scientific reporting has been the focus of prior commentary, more insidious aspects of such bias often escape attention by authors, reviewers, editorial boards, and commentators. Such bias is no longer simply academic because health care policy, which is increasingly predicated upon evidence-based scientific literature, may be adversely impacted by lack of balanced and objective publications in peer reviewed journals.

Time trends in radiologists' interpretive performance at screening mammography from the community-based Breast Cancer Surveillance Consortium, 1996-2004.

PURPOSE: To examine time trends in radiologists' interpretive performance at screening mammography between 1996 and 2004. MATERIALS AND METHODS: All study procedures were institutional review board approved and HIPAA compliant. Data were collected on subsequent screening mammograms obtained from 1996 to 2004 in women aged 40-79 years who were followed up for 1 year for breast cancer. Recall rate, sensitivity, and specificity were examined annually. Generalized estimating equation (GEE) and random-effects models were used to test for linear trend. The area under the receiver operating characteristic curve (AUC), tumor histologic findings, and size of the largest dimension or diameter of the tumor were also examined. RESULTS: Data on 2,542,049 subsequent screening mammograms and 12,498 cancers diagnosed in the follow-up period were included in this study. Recall rate increased from 6.7% to 8.6%, sensitivity increased from 71.4% to 83.8%, and specificity decreased from 93.6% to 91.7%. In GEE models, adjusted odds ratios per calendar year were 1.04 (95% confidence interval [CI]: 1.02, 1.05) for recall rate, 1.09 (95% CI: 1.07. 1.12) for sensitivity, and 0.96 (95% CI: 0.95, 0.98) for specificity (P < .001 for all). Random-effects model results were similar. The AUC increased over time: 0.869 (95% CI: 0.861, 0.877) for 1996-1998, 0.884 (95% CI: 0.879, 0.890) for 1999-2001, and 0.891 (95% CI: 0.885, 0.896) for 2002-2004 (P < .001). Tumor histologic findings and size remained constant. CONCLUSION: Recall rate and sensitivity for screening mammograms increased, whereas specificity decreased from 1996 to 2004 among women with a prior mammogram. This trend remained after accounting for risk factors. The net effect was an improvement in overall discrimination, a measure of the probability that a mammogram with cancer in the follow-up period has a higher Breast Imaging Reporting and Data System assessment category than does a mammogram without cancer in the follow-up period.

Identifying minimally acceptable interpretive performance criteria for screening mammography.

PURPOSE: To develop criteria to identify thresholds for minimally acceptable physician performance in interpreting screening mammography studies and to profile the impact that implementing these criteria may have on the practice of radiology in the United States. MATERIALS AND METHODS: In an institutional review board-approved, HIPAA-compliant study, an Angoff approach was used in two phases to set criteria for identifying minimally acceptable interpretive performance at screening mammography as measured by sensitivity, specificity, recall rate, positive predictive value (PPV) of recall (PPV(1)) and of biopsy recommendation (PPV(2)), and cancer detection rate. Performance measures were considered separately. In phase I, a group of 10 expert radiologists considered a hypothetical pool of 100 interpreting physicians and conveyed their cut points of minimally acceptable performance. The experts were informed that a physician's performance falling outside the cut points would result in a recommendation to consider additional training. During each round of scoring, all expert radiologists' cut points were summarized into a mean, median, mode, and range; these were presented back to the group. In phase II, normative data on performance were shown to illustrate the potential impact cut points would have on radiology practice. Rescoring was done until consensus among experts was achieved. Simulation methods were used to estimate the potential impact of performance that improved to acceptable levels if effective additional training was provided. RESULTS: Final cut points to identify low performance were as follows: sensitivity less than 75%, specificity less than 88% or greater than 95%, recall rate less than 5% or greater than 12%, PPV(1) less than 3% or greater than 8%, PPV(2) less than 20% or greater than 40%, and cancer detection rate less than 2.5 per 1000 interpretations. The selected cut points for performance measures would likely result in 18%-28% of interpreting physicians being considered for additional training on the basis of sensitivity and cancer detection rate, while the cut points for specificity, recall, and PPV(1) and PPV(2) would likely affect 34%-49% of practicing interpreters. If underperforming physicians moved into the acceptable range, detection of an additional 14 cancers per 100000 women screened and a reduction in the number of false-positive examinations by 880 per 100000 women screened would be expected. CONCLUSION: This study identified minimally acceptable performance levels for interpreters of screening mammography studies. Interpreting physicians whose performance falls outside the identified cut points should be reviewed in the context of their specific practice settings and be considered for additional training.

Breast cancer screening with imaging: recommendations from the Society of Breast Imaging and the ACR on the use of mammography, breast MRI, breast ultrasound, and other technologies for the detection of clinically occult breast cancer.

Screening for breast cancer with mammography has been shown to decrease mortality from breast cancer, and mammography is the mainstay of screening for clinically occult disease. Mammography, however, has well-recognized limitations, and recently, other imaging including ultrasound and magnetic resonance imaging have been used as adjunctive screening tools, mainly for women who may be at increased risk for the development of breast cancer. The Society of Breast Imaging and the Breast Imaging Commission of the ACR are issuing these recommendations to provide guidance to patients and clinicians on the use of imaging to screen for breast cancer. Wherever possible, the recommendations are based on available evidence. Where evidence is lacking, the recommendations are based on consensus opinions of the fellows and executive committee of the Society of Breast Imaging and the members of the Breast Imaging Commission of the ACR.

Solitary dilated duct identified at mammography: outcomes analysis.

OBJECTIVE: The purpose of this study is to review the clinical and pathologic outcomes for cases of solitary dilated duct identified at mammography. MATERIALS AND METHODS: For all screening mammography examinations during a 22-year period and all diagnostic mammography examinations during the last 10 of these years, the radiologists recorded the principal finding of each abnormal mammographic examination during image interpretation. Only examinations with the recorded finding of solitary dilated duct were studied. We examined radiology records to determine imaging follow-up and pathology records to determine histologic diagnosis, and we performed linkage with our regional tumor registry to identify cancers not biopsied at our institution. RESULTS: The finding of solitary dilated duct was recorded for nine (0.0038%) of 235,209 consecutive screenings and for 12 (0.041%) of 29,267 consecutive diagnostic mammography examinations. Five screening and five diagnostic cases were stable at follow-up (minimum interval, 2 years) and did not undergo biopsy; tumor registry linkage showed no subsequent cancer diagnosis. Biopsy was performed for four (44%) of nine screening and seven (58%) of 12 diagnostic cases. One cancer each (ductal carcinoma in situ) was identified from the screening and diagnostic populations, yielding positive predictive values of 11% (1/9) and 8% (1/12), respectively. CONCLUSION: Solitary dilated duct is a rare mammographic finding, this series being the largest reported to date. Although few cases are studied, solitary dilated duct appears to have a greater than 2% likelihood of malignancy, sufficiently high to suggest that a suspicious (BI-RADS 4a) assessment may be appropriate.

Impact of micrometastases in the sentinel node of patients with invasive breast cancer.

PURPOSE: Lymph node metastases are the most significant prognostic indicator for patients with breast cancer. Sentinel node biopsy (SNB) has led to an increase in the detection of micrometastases in the sentinel node (SN). This prospective study was designed to determine the survival impact of micrometastases in SNs of patients with invasive breast cancer. This study is based on the new sixth edition of the American Joint Committee on Cancer (AJCC) staging criteria. PATIENTS AND METHODS: Between January 1, 1992 and April 30, 1999, 790 patients entered this prospective study at the John Wayne Cancer Institute. The SN was examined first by hematoxylin and eosin (HE), and if the SN was negative with HE, then immunohistochemical staining was performed. The patients were then divided into four groups based on AJCC nodal staging: pN0(i-), no evidence of tumor (n = 486); pN0(i+), tumor deposit < or = 0.2 mm (n = 84); pN1mi, tumor deposit more than 0.2 mm but < or = 2 mm (n = 54), and pN1, tumor deposit more than 2 mm (n = 166). Disease-free survival (DFS) and overall survival (OS) were estimated using the Kaplan-Meier method. The log-rank test was used to determine differences in DFS and OS of patients from different groups. RESULTS: At a median follow-up of 72.5 months, the size of SN metastases was a significant predictor of DFS and OS. CONCLUSION: Patients with micrometastatic tumor deposits, pN0(i+) or pN1mi, do not seem to have a worse 8-year DFS or OS compared with SN-negative patients. As expected, there was a significant decrease in 8-year DFS and OS in patients with pN1 disease in the SN.