Abstract P3-02-02: Impact of breast density notification laws on radiology practices: A survey of 110 radiology facilities

Purpose: Breast Density Notification laws, passed in 15 states as of April 2014, mandate that breast density information be given to patients often without guidance on modalities, patient selection or funding for supplemental screening. The purpose of this study is to assess the impact of breast density notification laws on radiology practices, specifically regarding breast cancer risk assessment and supplemental screening studies.

Methods:

We performed an anonymous 20-question web-based survey to Society of Breast Imaging radiologists using a Qualtrics Survey Tool between 8/2013-3/2014, with questions on radiology practices, breast cancer risk assessment, breast density measurement, supplemental screening tests, and support for referring physicians and patients. We compared survey results between groups using Fisher’s exact test.

Results:

121 radiologists from 110 facilities (48 academic, 43 large private hospital, 15 small private hospital and 4 other) representing 34 USA states and 1 Canadian site responded. 49% of facilities (54/110) were in states with an enacted breast density notification law. 37% of facilities (40/109) performed risk assessment, 26% (28/109) did not perform risk assessment, and 38% (41/109) did not but reported family history/other risk factors, with no significant difference in performing risk assessment between facilities with or without an enacted law (p-value 0.71). Of the 37 facilities performing risk assessment, 60% used the Gail model, 22% used the Tyrer-Cuzick model and 11% used the modified Gail model (multiple answers allowed [m.a.a.]). Of the 15 facilities performing risk assessment, 40% answered "yes" when asked whether performing risk assessment is a new task because of the density law. Breast density was estimated by only visual assessment in 98% of facilities (103/105), and by computer-based determination with or without visual assessment in 2% (2/105). Supplemental screening studies offered included magnetic resonance imaging (MRI) (88%, 92/105), handheld whole breast ultrasound (HHWBUS) (48%, 50/105), tomosynthesis (39%, 41/105), and automated WBUS (8%, 8/105) (m.a.a.). There was no significant difference in supplemental screening studies offered between facilities with or without an enacted law (p-value 0.26). In anticipation of the law, facilities implemented HHWBUS (33%, 16/48), tomosynthesis (6%, 3/48), automated WBUS (6%, 3/48) or none (60%, 29/48) (m.a.a.). Facilities with the enacted law prepared for the law with referring physician discussions (69%, 34/49), website (49%, 24/49), educational talks for referring physicians (43%, 21/49) or patients (31%, 15/49) (m.a.a.).

Conclusion:

Our survey showed variations in available supplemental screening modalities and policy implementation at each facility. There was no significant difference in performing risk assessment and supplemental screening studies between facilities with or without an enacted breast density notification law.

Citation Format: Lina Nayak, Kanae K Miyake, Yueyi Irene Liu, William R Thomas, Edward A Sickles, Bonnie N Joe, Karen Lindfors, R J Brenner, Stephen Feig, Lawrence W Bassett, Jessica W Leung, Haydee Ojeda-Fournier, Jonathan Hargreaves, Elissa Price, Jafi A Lipson, Allison W Kurian, Elyse Love, Donna D Walgenbach, Lauren Ryan, Meg Durbin, Bruce L Daniel, Linda Garcia, Debra M Ikeda. Impact of breast density notification laws on radiology practices: A survey of 110 radiology facilities [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P3-02-02.

Abstract P2-01-01: Impact of California breast density notification law SB 1538 on California women and their health care providers

Purpose: To describe the impact of California Breast Density Notification law (SB 1538) on policy development, policy implementation and supplemental screening strategies within California medical facilities. SB 1538 mandates that breast density information be given to patients but provides no funding for supplemental screening, no guidance on how to triage women for supplemental screening nor which imaging modalities to use.

Methods:

As a result of the law, the California Breast Density Information Group (CBDIG) formed from academic and private practice radiologists and risk assessment experts, reviewing scientific literature and nationally recognized guidelines to provide evidence-based recommendations regarding supplemental screening in women with dense breast tissue. A survey was sent to 6 academic and 3 large private practices in California to record their experience in implementing the law.

Results: CBDIG created a public, institution-neutral, evidence-based website, “breastdensity.info”, that includes information and recommendations regarding supplemental breast screening, with triage for supplemental MRI or US based on breast cancer risk assessment using genetic or family history risk models. CBDIG facilities worked with referring health care providers to inform them of the new law, educated their staff and technologists on implementing policy, and developed notification strategies to comply with legislation.

The survey showed that all 9 facilities recommended supplemental screening based on family history models or genetic testing. 3/9 calculated breast cancer risk in the breast imaging clinic, and 2/9 emailed a risk survey to the patient. 3/9 reported risk in the radiology report, and 1/9 reported risk only if the patient was high risk. Risk assessments were performed by technologists and risk assessment health practitioners. 8/9 facilities estimated breast density by visual methods, and 1/9 by computer. All facilities performed screening breast MRI, 4/9 performed handheld screening US, and 2/9 tomosynthesis. 1/9 obtained tomosynthesis in anticipation of the law, 2/9 are trying to obtain automated whole breast US, and 3/9 are trying to obtain tomosynthesis. Facilities expressed concerns about additional false-positive biopsies produced by supplemental screenings, out-of-pocket expenses for women, and disparities (low income) in notified populations.

Conclusion: SB 1538 resulted in the formation of the CBDIG and the website, “breastdensity.info”. Our survey showed variations in imaging modalities available and policy implementation at each facility. Given that several states currently have breast density laws or have laws that will become effective in the near future, it is important for breast imagers and clinicians to be informed of the current literature, realize the variation in equipment and policies at various facilities, and develop recommendation strategies to guide patients seeking supplemental screening. We plan to follow up this survey with a larger survey of the Society of Breast Imagers at a later date.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-01-01.

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.

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.

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.

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.

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.

Disclosing harmful mammography errors to patients

PURPOSE

To assess radiologists' attitudes about disclosing errors to patients by using a survey with a vignette involving an error interpreting a patient's mammogram, leading to a delayed cancer diagnosis.

MATERIALS AND METHODS

We conducted an institutional review board-approved survey of 364 radiologists at seven geographically distinct Breast Cancer Surveillance Consortium sites that interpreted mammograms from 2005 to 2006. Radiologists received a vignette in which comparison screening mammograms were placed in the wrong order, leading a radiologist to conclude calcifications were decreasing in number when they were actually increasing, delaying a cancer diagnosis. Radiologists were asked (a) how likely they would be to disclose this error, (b) what information they would share, and (c) their malpractice attitudes and experiences.

RESULTS

Two hundred forty-three (67%) of 364 radiologists responded to the disclosure vignette questions. Radiologists' responses to whether they would disclose the error included "definitely not" (9%), "only if asked by the patient" (51%), "probably" (26%), and "definitely" (14%). Regarding information they would disclose, 24% would "not say anything further to the patient," 31% would tell the patient that "the calcifications are larger and are now suspicious for cancer," 30% would state "the calcifications may have increased on your last mammogram, but their appearance was not as worrisome as it is now," and 15% would tell the patient "an error occurred during the interpretation of your last mammogram, and the calcifications had actually increased in number, not decreased." Radiologists' malpractice experiences were not consistently associated with their disclosure responses.

CONCLUSION

Many radiologists report reluctance to disclose a hypothetical mammography error that delayed a cancer diagnosis. Strategies should be developed to increase radiologists' comfort communicating with patients.

Radiologist characteristics associated with interpretive performance of diagnostic mammography

BACKGROUND

Extensive variability has been noted in the interpretive performance of screening mammography; however, less is known about variability in diagnostic mammography performance.

METHODS

We examined the performance of 123 radiologists who interpreted 35895 diagnostic mammography examinations that were obtained to evaluate a breast problem from January 1, 1996, through December 31, 2003, at 72 facilities that contribute data to the Breast Cancer Surveillance Consortium. We modeled the influence of radiologist characteristics on the sensitivity and false-positive rate of diagnostic mammography, adjusting for patient characteristics by use of a Bayesian hierarchical logistic regression model.

RESULTS

The median sensitivity was 79% (range = 27%-100%) and the median false-positive rate was 4.3% (range = 0%-16%). Radiologists in academic medical centers, compared with other radiologists, had higher sensitivity (88%, 95% confidence interval [CI] = 77% to 94%, versus 76%, 95% CI = 72% to 79%; odds ratio [OR] = 5.41, 95% Bayesian posterior credible interval [BPCI] = 1.55 to 21.51) with a smaller increase in their false-positive rates (7.8%, 95% CI = 4.8% to 12.7%, versus 4.2%, 95% CI = 3.8% to 4.7%; OR = 1.73, 95% BPCI = 1.05 to 2.67) and a borderline statistically significant improvement in accuracy (OR = 3.01, 95% BPCI = 0.97 to 12.15). Radiologists spending 20% or more of their time on breast imaging had statistically significantly higher sensitivity than those spending less time on breast imaging (80%, 95% CI = 76% to 83%, versus 70%, 95% CI = 64% to 75%; OR = 1.60, 95% BPCI = 1.05 to 2.44) with non-statistically significant increased false-positive rates (4.6%, 95% CI = 4.0% to 5.3%, versus 3.9%, 95% CI = 3.3% to 4.6%; OR = 1.17, 95% BPCI = 0.92 to 1.51). More recent training in mammography and more experience performing breast biopsy examinations were associated with a decreased threshold for recalling patients, resulting in similar statistically significant increases in both sensitivity and false-positive rates.

CONCLUSIONS

We found considerable variation in the interpretive performance of diagnostic mammography across radiologists that was not explained by the characteristics of the patients whose mammograms were interpreted. This variability is concerning and likely affects many women with and without breast cancer.

The Expert Witness: Understanding the Rationale

The origins of the use of expert witnesses to assist courts in helping understand the required conduct in determining the standard of care provides a basis for recognizing the consultant role sought in judicial proceedings. Both rules of evidence and court decisions have evolved in a manner that encourages the introduction of expert testimony while conditioning its use to avoid unfair bias. Trial court judges decide on permitting such testimony, while legal counsel is responsible for helping juries determine its importance and reliability. Certain types of restrictions and adverse consequences for misstatements exist but are subordinated to the trial process in most circumstances, a process that varies among different jurisdictions.

Alternative Breast-Imaging Approaches

Although conventional breast-imaging techniques routinely include mammography and ultrasound, growing interest in other approaches, perhaps most notably MR imaging, has drawn increasing attention to exploiting the anatomic and physiologic basis for understanding breast cancer. Nuclear medicine techniques have been applied in several circumstances with the intent of approaching or defining a role for molecular imaging, exemplified by the use of F-18 fluorodeoxyglucose and positron emission tomography. Other techniques, including exploitation of additional components of the electromagnetic spectrum, have provided novel concepts that may ripen into clinical use.

Communication errors in radiology: a liability cost analysis

PURPOSE

We evaluated the economic effect on radiologists involved in litigation of failures in communication of results.

METHOD

We examined claims data from the Physicians Insurers Association of America 2002 report on breast cancer and identified malpractice cases in which miscommunication, rather than misdiagnosis, was the primary cause for litigation.

RESULTS

The average indemnity payment for primary errors in communication by radiologists was between $228,000 and $236,000, or twice as high as when appropriate communication occurred. As a percentage of total indemnity payments to plaintiffs, such awards were 15 times higher than when communication was effective.

CONCLUSIONS

Notwithstanding diagnostic accuracy, errors attributable to ineffective communication of results account for high indemnity awards. These errors can be easily resolved in clinical practice.

American College Of Radiology/Society of Breast Imaging curriculum for resident and fellow education in breast imaging

The ACR and the Society of Breast Imaging have revised the curriculum for resident and fellow education in breast imaging on the basis of substantial changes in breast imaging practice since the initial curriculum was published in 2000. This curriculum provides guidance to academic chairs, residency program directors, and academic section chiefs in assessing and improving their residency and fellowship training programs and indicates to residents and breast imaging fellows the topics they need to learn and the experience they should try to acquire during their training. Radiologists already in practice also may find the curriculum useful in outlining the material they need to know to remain up to date in the practice of breast imaging.

To err is human, to correct divine: the emergence of technology-based communication systems

An increasing emphasis has been placed on the importance of timely communication of imaging results, especially to the extent that clinical management decisions are modified by the information. Various methods of transmitting results have been proposed and developing technology can now be applied to helping to ensure the timely receipt of such results in a busy clinical environment. Stratifying levels of urgency, ensuring redundancy of potential recipients of such information, and the ability to assess desired benchmarks are objectives that involve many stakeholders, including radiologists, treating physicians, and institutions. An enterprise approach to this challenge, including commercially available systems, offers a potentially cost-effective solution that addresses both risk management and quality improvement goals.

Prevalence of Rupture in Inamed Silicone Breast Implants

BACKGROUND

Silicone breast implants have been used for decades and are arguably the most studied implantable device. However, the vast body of scientific literature has been unable to establish a definitive rupture rate. Various studies have evaluated implant rupture, but the meaningfulness of these data was confounded by the inclusion of different generations of implants and multiple manufacturers' implants and the selection of subjects who were already suspected of having ruptured implants. The authors' study was designed to acquire long-term rupture data specific to Inamed's third-generation silicone breast implants using magnetic resonance imaging technology.

METHODS

A total of 106 women with at least one Inamed silicone breast implant (styles 40, 110, and 120) were enrolled in this multicenter, cross-sectional study. The majority received implants for cosmetic augmentation (n = 77, 72.6 percent), with a smaller number having undergone breast reconstruction (n = 11, 10.4 percent) or revision of previous breast implant operations (n = 18, 17.0 percent). Most subjects were Caucasian (n = 99, 93.4 percent) with a median age at implantation of 34 years (range, 18 to 70 years). Enrolled subjects underwent a physical examination and magnetic resonance imaging screening at one of five sites to determine the prevalence of asymptomatic rupture.

RESULTS

A total of 199 implants were evaluated, with a median implantation time of 10.9 years (range, 9.5 to 13.2 years). Overall, 183 implants (92.0 percent) showed no evidence of rupture, 12 (6.0 percent) showed evidence of rupture, and four (2.0 percent) were indeterminate. All indeterminate evaluations were considered ruptures, providing a worst-case rupture prevalence of 8.0 percent.

CONCLUSION

The study results establish a rupture prevalence rate of 8.0 percent at 11 years for Inamed's silicone breast implants.

Computer-aided detection as evidence in the courtroom: potential implications of an appellate court's ruling

OBJECTIVE

The use of computer-aided detection (CAD) in radiology has been studied for different organ systems. As with any new technology, its impact on determinations of standards of clinical practice is an evolving one that is often defined by its acceptability not only in medical forums but also as defined by courts of law.

CONCLUSION

We discuss the first known appellate legal decision regarding the acceptability of CAD as it relates to the clinical practice of mammography.

Medical-Legal Issues Associated with Breast Fine Needle Aspiration Biopsy

This article discusses medical and legal issues associated with breast fine needle aspiration biopsy and develops risk-management considerations for clinical practice. Basic legal considerations are first discussed, including the law of negligence as it applies to breast fine needle aspiration. The variable concept of duty to patients is reviewed. Communication of diagnosis, both formally and informally, in the medical setting is covered. The claims review process is then discussed. The meaning of misdiagnosis, including overdiagnosis and delay of diagnosis, is discussed in terms of legal harm and expert review.

Mammography with breast cushions

OBJECTIVE

We conducted a randomized clinical trial to determine the impact on pain and image quality when breast cushions were used to pad the surfaces of the mammography equipment during film-screen mammography.

METHODS

We recruited a consecutive volunteer sample of 394 participants. Breast cushions were used for only one breast, with laterality and sequence of use assigned randomly. Data collected from participants included demographic data, rating of pain from previous mammography, and rating of pain from present mammography using both a numeric rating scale and a visual analogue scale. Research assistants also collected breast compression and radiation exposure data. Radiologists were blinded to the laterality of cushion assignment while reading the mammograms and assessing image quality.

RESULTS

Participants were primarily white women (75.3%), mean age 55.4 years. Most (94.4%) reported having previous mammography. Eight percent (n = 32) of those surveyed had thought about skipping or delaying mammography because of the pain involved. The pain associated with mammography was significantly (p < .001) less during oblique and craniocaudal views when breast cushions were used during the procedure. Retakes were required for 2% of the 1576 views with the most common reason being positioning (53%).

CONCLUSION

The use of breast cushions significantly reduced the pain during film-screen mammography. Image quality with the cushions was reduced in a very small subset of women probably due to the difficulty in positioning the breast without visual clues. More research needs to be done prior to the routine use of these cushions in clinical practice.

Computer-aided detection output on 172 subtle findings on normal mammograms previously obtained in women with breast cancer detected at follow-up screening mammography

PURPOSE

To evaluate, by using a computer-aided detection (CAD) program, the nonspecific findings on normal screening mammograms obtained in women in whom breast cancer was later detected at follow-up screening mammography.

MATERIALS AND METHODS

Four hundred ninety-three mammogram pairs-an initial negative screening mammogram and a subsequently obtained screening mammogram showing cancer-were collected. The mean interval between examinations was 14.6 months. In 169 cases, in which 172 cancers were later depicted, findings on the initial mammogram were subtle enough that either none or only one or two of five blinded radiologists recommended screening recall. On the initial negative mammograms, of the 172 areas where cancer later developed, 137 (80%) had subtle nonspecific findings and were retrospectively judged as having a benign or normal appearance. The mammograms with these subtle findings were evaluated with a commercially available CAD program, and the numbers of CAD marks on these nonspecific findings were analyzed.

RESULTS

Of the 172 cancers, 129 (75%) were invasive and 43 (25%) were ductal carcinoma in situ. The CAD program marked 72 (42%) of the 172 findings that subsequently developed into cancer: 24 (29%) of 82 findings recalled by none, 25 (49%) of 51 findings recalled by one, and 23 (59%) of 39 findings recalled by two of the five radiologists. Among the 137 areas with nonspecific normal or benign findings, 41 (30%) areas where cancer subsequently developed were marked by the CAD program.

CONCLUSION

A subset of cancers have perceptible but nonspecific mammographic findings that may be marked by a CAD program, even when the findings do not warrant recall as judged at blinded and unblinded radiologist review. The authors believe failure to act on such nonspecific but CAD-marked findings prospectively does not constitute interpretation below a reasonable standard of care.

Screening-detected Breast Cancer in a Man withBRCA2Mutation: Case Report

Current indications for breast cancer screening in the male population are lacking, although family history of breast cancer may be such an indication. The authors describe a man with a history of clinically diagnosed right breast cancer who subsequently tested positive for the breast cancer susceptibility gene BRCA2 and received a diagnosis of mammographically detected left breast cancer at screening. The authors discuss the clinical implications of this approach to detecting male breast cancer.

The malpractice liability crisis

Most medical malpractice cases are tried under the civil tort of negligence and are often triggered by adverse outcomes. These proceedings are aimed primarily at determining whether the conduct of a health care provider was reasonable. Such legal actions have mostly been subject to state jurisdiction. Increasingly, a number of factors are converging that are threatening the continued practice of medicine in some states and hence patients' access to care. These include higher amounts of monetary damages awarded to successful plaintiffs, consequent rising malpractice premiums, and the threatened economic insolvency of medical liability insurance carriers as a result of the broader economic downturn. The result is a serious public health dilemma. The national scope of the problem has been considered a crisis, which has prompted unprecedented federal legislative proposals directed toward providing new and preemptive parameters for capitated noneconomic damages, restrictions on certain civil procedures affecting lawsuit outcomes, and methods for attorney compensation, which some states have either not previously addressed or found unconstitutional. A survey of different states' problems and common issues should assist the reader in understanding the nature of the crisis and proposed solutions.

Breast Cancer Evaluation: Medical Legal Issues

Delay in diagnosis of breast cancer is the leading cause for malpractice lawsuits against physicians. Most cases are tried under civil law and, more specifically, the tort of negligence which defines departures from conduct of a reasonable and prudent physician under similar circumstances. The role of both the clinician and imager, separately and in concert, needs to be understood with respect to accomplishing early diagnosis and avoiding potential legal exposure. An understanding of basic legal concepts as they apply to medical practice should provide health care providers a perspective from which to apply their skills and avoid unnecessary legal exposure.

Analysis of 172 subtle findings on prior normal mammograms in women with breast cancer detected at follow-up screening

PURPOSE

To retrospectively review nonspecific findings on prior screening mammograms to determine what features were most often deemed normal or benign despite the development of breast cancer in the same location detected at follow-up screening.

MATERIALS AND METHODS

Four hundred ninety-three pairs of consecutive mammographic findings were collected from 13 institutions, consisting of initial normal screening findings and a subsequent finding of cancer at screening (mean interval between examinations, 14.6 months). One designated radiologist reviewed each pair of mammograms and determined that 286 findings were judged visible at prior examination in locations where cancer later developed. Five blinded radiologists independently reviewed the prior findings in these 286 cases, identifying 169 mammograms (172 cancers) with findings so subtle that none or only one or two of the five radiologists recommended screening recall. Two unblinded radiologists reviewed the initial and subsequent findings and recorded descriptors and assessments for each finding and subjective factors influencing why, although the lesion was perceptible, it might have been undetected or not recalled.

RESULTS

Of 172 cancers, 129 (75%) were invasive (112 T1 tumors and 17 T2 tumors or higher; median diameter, 10 mm), and 43 (25%) were ductal carcinoma in situ (median size, 10 mm). On the prior mammograms, 80% (137 of 172) of these cancers had subtle nonspecific findings where cancer later developed, and most were assessed as being normal or benign in appearance.

CONCLUSION

There is a subset of cancers that display perceptible but nonspecific mammographic findings that do not warrant recall, as judged by both a majority of blinded radiologists and by unblinded reviewers. We believe failure to act on these nonspecific findings prospectively does not necessarily constitute interpretation below a reasonable standard of care.

Percutaneous core needle biopsy of radial scars of the breast: when is excision necessary?

OBJECTIVE

. This study was conducted to evaluate the outcome of cases of radial scar diagnosed by percutaneous core needle biopsy.

MATERIALS AND METHODS

Of 198 nonpalpable lesions diagnosed with radial scars found at core needle biopsy, 157 lesions constituting the study group had undergone surgical excision (n = 102) or mammographic surveillance after biopsy for at least 24 months (median, 38 months; n = 55). Mammographic lesion type, lesion size, biopsy guidance method, biopsy device, number of specimens per lesion, and presence of atypical hyperplasia at percutaneous biopsy were retrospectively analyzed. Results were compared with histologic findings at surgery or mammographic findings during surveillance.

RESULTS

. Carcinoma was found at excision in 28% (8/29) of lesions with associated atypical hyperplasia at percutaneous biopsy and 4% (5/128) of lesions without associated atypia (p < 0.0001). In the latter group, carcinoma was found at excision in 3% (2/60) of masses, 8% (3/40) of architectural distortions, and 0% (0/28) of microcalcification lesions. Malignancy was missed in 9% (5/58) of lesions biopsied with a spring-loaded device and in 0% (0/70) of lesions biopsied with a directional vacuum-assisted device (p = 0.01); and in 8% (5/60) of lesions sampled with less than 12 specimens per lesion and 0% (0/68) sampled with 12 or more specimens (p = 0.015). Lesion type, maximal lesion diameter, and type of imaging guidance (stereotactic or sonographic) were not significant factors in determining the presence of malignancy.

CONCLUSION

. Diagnosis of radial scar based on core needle biopsy is likely to be reliable when there is no associated atypical hyperplasia at percutaneous biopsy, when the biopsy includes at least 12 specimens, and when mammographic findings are reconciled with histologic findings. When the lesion diagnosed by core needle biopsy as radial scar does not meet these criteria, excisional biopsy is indicated.

Insecticide susceptibility in Coptotermes formosanus and Reticulitermes virginicus (Isoptera: Rhinotermitidae)

Lethal time to mortality responses were established for eight insecticides against workers and soldiers of the Formosan subterranean termite, Coptotermes formosanus Shiraki, and workers of Reticulitermes virginicus (Banks). There were significant differences in the tolerance ratios between workers of C. formosanus colonies to all toxicants tested except fipronil. One colony was 16 times more tolerant than another to deltamethin. C. formosanus soldiers had significant differences in tolerance ratios among colonies exposed to all toxicants except chlorpyrifos. Methoxychlor, permethrin, deltamethrin, and fipronil did not kill soldiers from two, one, one, and three colonies, respectively, within 8 h. Seventy-five percent of R. virginicus colonies were significantly less susceptible than the most susceptible colony to chlordane, methoxychlor, chlorpyrifos, cypermethrin, and fipronil, with 50% of the colonies less susceptible to permethrin and bendiocarb. In 50% of C. formosanus colonies the worker lethal time curves displayed substantial flattening in response to permethrin, and deltamethrin. Lethal time curses for C. formosanus soldiers exposed to chlordane, chlorpyrifos, permethrin, cypermethrin, deltamethrin, and bendiocarb showed substantial flattening. R. virginicus workers demonstrated substantial curve flattening when exposed to chlordane, methoxychlor, chlorpyrifos, deltamethrin, and fipronil. These findings indicate substantial intercolony and intra-colony differences in susceptibility to insecticides.

Stereotactic core-needle breast biopsy: a multi-institutional prospective trial

PURPOSE

To assess the accuracy of stereotactic core-needle biopsy (CNB) of nonpalpable breast lesions within the context of clinically important parameters of anticipated tissue-sampling error and concordance with mammographic findings.

MATERIALS AND METHODS

CNB was performed in 1,003 patients, with results validated at surgery or clinical and mammographic follow-up. Mammographic findings were scored according to the American College of Radiology Breast Imaging Reporting and Data System with a similar correlative scale for histopathologic samples obtained at either CNB or surgery. Agreement of CNB findings with surgical findings or evidence of no change during clinical and mammographic follow-up (median, 24 months) for benign lesions was used to determine results. Three forms of diagnostic discrimination measures (strict, working [strict conditioned by tissue sampling error], applied [working conditioned by concordance of imaging and CNB findings) were used to evaluate the correlation of CNB, surgical, and follow-up results.

RESULTS

Strict, working, and applied sensitivities were 91% +/- 1.9; 92% +/- 1.8, and 98% +/- 0.9, respectively; strict, working, and applied specificities were 100%, 98% +/- 0.8, and 73% +/- 0.9; strict, working, and applied accuracies were 97%, 96%, and 79%.

CONCLUSION

Percutaneous stereotactic CNB is an accurate method to establish a histopathologic diagnosis of nonpalpable breast lesions. Accuracy increases when additional surgery is performed for lesions with anticipated sampling error or when CNB findings are discordant with mammographic findings. An understanding of the interrelationship among these parameters is necessary to properly assess results.

Toxicity and in vitro metabolism of t-permethrin in eastern subterranean termite (Isoptera: Rhinotermitidae)

Toxicity and metabolism of t-permethrin were evaluated in two colonies (UF and ARS) of the eastern subterranean termite, Reticulitermes flavipes (Kollar), collected in Gainesville, FL. The UF colony (LC50 = 1.86 micrograms per vial) was approximately twofold more tolerant of t-permethrin than the ARS colony (LC50 = 0.89 microgram per vial) at the LC50. The synergists piperonyl butoxide and S,S,S-tributylphosphorotrithioate increased t-permethrin toxicity four- and threefold (at the LC50) in the UF and ARS colonies, respectively. Despite these differences in t-permethrin susceptibility, microsomal oxidase activities toward surrogate substrate (aldrin epoxidase, and methoxyresorufin O-demethylase), cytochrome P450 content, and microsomal esterase activity toward alpha-naphthyl acetate did not differ significantly between the colonies. Moreover, no significant differences in qualitative and quantitative metabolism of [14C]t-permethrin were observed between the UF and ARS colonies for three enzyme sources (microsomal oxidase, microsomal esterase, and cytosolic esterase). Based on in vitro metabolism assays, the major detoxification route of t-permethrin in the UF and ARS termite colonies appears to be hydrolysis catalyzed by microsomal esterases.

Origin of metallic particles resembling microcalcifications on mammograms after use of abrasive cautery-tip cleaning pads during breast surgery: experimental demonstration

PURPOSE

To determine if the act of cleaning a cautery tip with an abrasive pad dislodges radiopaque particles that can be transferred to breast tissue during surgery, thereby mimicking microcalcifications at mammography.

MATERIALS AND METHODS

Mock breast surgery was performed by cauterizing bovine liver or fresh, normal, human breast tissue. The cautery tip was rubbed against a cleaning pad five to 20 times in the manner used intraoperatively and was touched on separate breast tissue specimens two to six times. Specimen radiography was then performed. Thirty-six breast specimens were used in three experiments, including 28 used for the experimental conditions and eight control specimens.

RESULTS

Particles collected from the cleaning pads resembled microcalcifications. After cauterization of liver, breast tissue, or both, in series, particles transferred from the cautery tip to breast tissue specimens could be identified on specimen radiographs. Transfer of particles after cautery of breast tissue occurred with increased numbers of rubs and specimen contacts.

CONCLUSION

Radiopaque aluminum oxide particles from abrasive cautery-tip cleaning pads can be dislodged and transferred to breast tissue during surgery. Scrutiny of high-detail, spot-compression, magnification mammograms will help identify these particles. Simple measures to mitigate particle transfer during breast surgery can prevent this problem and obviate a potential second procedure to remove particles mistaken for microcalcifications.

False-negative mammograms. Medical, legal, and risk management implications

From a strictly biologic perspective, delay in diagnosis of breast cancer is axiomatic. The number of cell divisions that must occur before detection is possible by either clinical or mammographic methods means that a finite time has occurred in which the outcome for any given case may have already been determined. That early detection and diagnosis of breast cancer lead to improved survival may be intuitive, but clinical trials have been necessary to validate the concept. Delay in diagnosis is unavoidable but the period of delay may be lessened in many cases, prompting earlier intervention and impacting outcomes. Mammography is an important vehicle for such earlier intervention and the issue of the false-negative mammogram is of concern to the radiology community, the lay community, and the courts. Mammographic interpretation has not yet approached a sufficiently standardized benchmark. Detection and diagnosis are dependent on a series of factors that need to be integrated to achieve the dual goals of timely intervention for bonafide purposes and reduction of unnecessary procedures and interventions. Some of the reasons for delay in diagnosis are unavoidable, beginning with the absence of clinical or imaging features of malignancy and extending to limitations of sufficiently specific features to prompt intervention. On the other hand, other reasons are avoidable and attention to many of these causes should lessen the incidence of such delay. Regardless of the reason, those women who feel that their breast cancer should have been diagnosed at an earlier time may consider subjecting their mammographic studies to independent reviews. At such a point, the precise reasons for delay may be better analyzed, all in an attempt to provide an adequate reconciliation of what has come to be known as the false-negative mammogram.

Accuracy of screening mammography using single versus independent double interpretation

OBJECTIVE

We conducted an analysis among 31 community radiologists to identify the average change in screening mammography interpretive accuracy afforded by independent double interpretation.

MATERIALS AND METHODS

We assessed interpretive accuracy using a stratified random sample of test mammograms that included 30 women with cancer and 83 without. Radiologists were unaware of clinical information and of each other's assessments. We describe accuracy for individual radiologists and for double interpretation, including average sensitivity, specificity, diagnostic likelihood ratios positive and negative, and area under the receiver operating characteristic (ROC) curve. We also assessed weighted and nonweighted kappa statistics among all 465 pairs of radiologists and 31,465 pairs of unique pairs. The assessment for double interpretations used the "highest" (i.e., most abnormal) assessment of the two radiologists. We calculated the difference between each radiologist's individual accuracy and the average accuracy across that radiologist's 30 double interpretations.

RESULTS

We found the following average accuracy statistics for individual radiologists: sensitivity, 79%; specificity, 81%; diagnostic likelihood ratio positive, 5.53; diagnostic likelihood ratio negative, 0.26; and area under the ROC curve, 0.85. The mean kappa statistic among radiologists for cancer cases increased with double interpretation from 0.59 to 0.70, and for noncancer cases from 0.30 to 0.34. Double interpretation resulted in an average increase in sensitivity of 7%, an average decrease in specificity of 11%, a decrease in diagnostic likelihood ratio positive of 2.35, a decrease in diagnostic likelihood ratio negative of 0.06, and an increase in area under the ROC curve of 0.02.

CONCLUSION

Independent double interpretation does not increase accuracy as measured by the area under the ROC curve.

Lesions entirely removed during stereotactic biopsy: preoperative localization on the basis of mammographic landmarks and feasibility of freehand technique--initial experience

Seven patients with mammographic lesions entirely removed at percutaneous core needle biopsy that required wider excision underwent freehand localization of the site of the prior lesion with orthogonal and reproducible mammographic landmarks to guide needle placement. Successful excision was accomplished in all cases, as evidenced by similar histopathologic findings, fibrin bands or collagen, and core needle biopsy tract at microscopy.

Transmission thresholds for dengue in terms of Aedes aegypti pupae per person with discussion of their utility in source reduction efforts

The expense and ineffectiveness of drift-based insecticide aerosols to control dengue epidemics has led to suppression strategies based on eliminating larval breeding sites. With the notable but short-lived exceptions of Cuba and Singapore, these source reduction efforts have met with little documented success; failure has chiefly been attributed to inadequate participation of the communities involved. The present work attempts to estimate transmission thresholds for dengue based on an easily-derived statistic, the standing crop of Aedes aegypti pupae per person in the environment. We have developed these thresholds for use in the assessment of risk of transmission and to provide targets for the actual degree of suppression required to prevent or eliminate transmission in source reduction programs. The notion of thresholds is based on 2 concepts: the mass action principal-the course of an epidemic is dependent on the rate of contact between susceptible hosts and infectious vectors, and threshold theory-the introduction of a few infectious individuals into a community of susceptible individuals will not give rise to an outbreak unless the density of vectors exceeds a certain critical level. We use validated transmission models to estimate thresholds as a function of levels of pre-existing antibody levels in human populations, ambient air temperatures, and size and frequency of viral introduction. Threshold levels were estimated to range between about 0.5 and 1.5 Ae. aegypti pupae per person for ambient air temperatures of 28 degrees C and initial seroprevalences ranging between 0% to 67%. Surprisingly, the size of the viral introduction used in these studies, ranging between 1 and 12 infectious individuals per year, was not seen to significantly influence the magnitude of the threshold. From a control perspective, these results are not particularly encouraging. The ratio of Ae. aegypti pupae to human density has been observed in limited field studies to range between 0.3 and >60 in 25 sites in dengue-endemic or dengue-susceptible areas in the Caribbean, Central America, and Southeast Asia. If, for purposes of illustration, we assume an initial seroprevalence of 33%, the degree of suppression required to essentially eliminate the possibility of summertime transmission in Puerto Rico, Honduras, and Bangkok, Thailand was estimated to range between 10% and 83%; however in Mexico and Trinidad, reductions of >90% would be required. A clearer picture of the actual magnitude of the reductions required to eliminate the threat of transmission is provided by the ratio of the observed standing crop of Ae. aegypti pupae per person and the threshold. For example, in a site in Mayaguez, Puerto Rico, the ratio of observed and threshold was 1.7, meaning roughly that about 7 of every 17 breeding containers would have to be eliminated. For Reynosa, Mexico, with a ratio of approximately 10, 9 of every 10 containers would have to be eliminated. For sites in Trinidad with ratios averaging approximately 25, the elimination of 24 of every 25 would be required. With the exceptions of Cuba and Singapore, no published reports of sustained source reduction efforts have achieved anything near these levels of reductions in breeding containers. Practical advice on the use of thresholds is provided for operational control projects.