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Bonnie C Yankaskas

Publications and source records attributed to Bonnie C Yankaskas.

At least 19 recordsLinked to original sources

Prospective breast cancer risk prediction model for women undergoing screening mammography.

BACKGROUND: Risk prediction models for breast cancer can be improved by the addition of recently identified risk factors, including breast density and use of hormone therapy. We used prospective risk information to predict a diagnosis of breast cancer in a cohort of 1 million women undergoing screening mammography. METHODS: There were 2,392,998 eligible screening mammograms from women without previously diagnosed breast cancer who had had a prior mammogram in the preceding 5 years. Within 1 year of the screening mammogram, 11,638 women were diagnosed with breast cancer. Separate logistic regression risk models were constructed for premenopausal and postmenopausal examinations by use of a stringent (P<.0001) criterion for the inclusion of risk factors. Risk models were constructed with 75% of the data and validated with the remaining 25%. Concordance of the predicted with the observed outcomes was assessed by a concordance (c) statistic after logistic regression model fit. All statistical tests were two-sided. RESULTS: Statistically significant risk factors for breast cancer diagnosis among premenopausal women included age, breast density, family history of breast cancer, and a prior breast procedure. For postmenopausal women, the statistically significant factors included age, breast density, race, ethnicity, family history of breast cancer, a prior breast procedure, body mass index, natural menopause, hormone therapy, and a prior false-positive mammogram. The model may identify high-risk women better than the Gail model, although predictive accuracy was only moderate. The c statistics were 0.631 (95% confidence interval [CI] = 0.618 to 0.644) for premenopausal women and 0.624 (95% CI = 0.619 to 0.630) for postmenopausal women. CONCLUSION: Breast density is a strong additional risk factor for breast cancer, although it is unknown whether reduction in breast density would reduce risk. Our risk model may be able to identify women at high risk for breast cancer for preventive interventions or more intensive surveillance.

Adult↗

Methodological issues in international comparison of interval breast cancers.

International comparisons of interval cancers (IC) are important to better understand the relationship between programmes' performance and screening practices. In this respect, differences in (i) definition, (ii) identification and (iii) quantification of IC have received little attention. To examine these 3 comparability issues and activities involving IC, an assessment was conducted among member countries of the International Breast Cancer Screening Network, and the impact of accuracy of identification and quantification practices was estimated using 1996-98 data from the Dutch breast cancer screening programme. Information was obtained from 19 screening programmes in 18 countries, 16 of which acknowledged the coexistence of opportunistic screening. IC data were collected to evaluate performance of the screening programme (100% of programmes) and the radiologists (89%); 53% of programmes had a designated review process for IC. Most programmes (84%) agreed with the European Guidelines definition of IC, but a case situation exercise evidenced substantial discrepancy in classification of cancers that occurred after a positive screen. Completeness of identification of IC appears to contribute most to international variation, and cannot be easily controlled for in methodologically rigorous comparisons. Statistically significant differences of about 4% were measured between quantification methods for IC. An operational definition of IC is proposed to enhance international comparability. Valid comparisons of IC are possible with careful attention to the definition but true differences in IC frequency across screening programmes should exceed 10% to be possibly indicative of real differences between programmes.

Adult↗

Screening mammography after breast cancer treatment: patterns in community practice.

BACKGROUND: Guidelines for screening women post-breast cancer treatment are generally lacking. This study was conducted to review the literature on guidelines for this population and to evaluate whether there is a common practice in the community for following these women. METHODS: The literature was reviewed for presence of published or inferred guidelines. Data were then used from the Carolina Mammography Registry (CMR) to see if patterns exist in community practice. For the years 1995-1999, 3081 women with a new diagnosis of unilateral breast cancer and a post-treatment screening mammogram in CMR were included. Recommendations for initial mammographic examination and intervals of subsequent mammograms post-treatment were described and tested for patterns of follow-up time. RESULTS: The only evidence-based guidelines found for post-treatment mammographic examinations were from the American Society of Clinical Oncology. They recommend 6 month follow-up initially followed by 12 month follow-up if findings remain stable. Among the 3081 women included in the study, 17.4% were recommended to return at 6 months post-treatment following their initial mammogram. Of the women who had at least three post-cancer mammograms (1592/3081), 82.6% were recommended for 12 month intervals at all three visits; only 2.1% of women were recommended for 6 month intervals at all three visits. CONCLUSIONS: This study found that most community-based radiologists included in our study recommend following women at 12 month intervals post-treatment. Whether this 12 month screening interval is optimal for detecting recurrent cancers is not known and should be the focus of future research.

Adult↗

Improving the concordance of mammography assessment and management recommendations.

PURPOSE: To retrospectively compare the concordance of initial and final assessment categories for mammograms with management recommendations made before and after the final rules of the Mammography Quality Standards Act (MQSA) were in effect for screening and diagnostic mammography. MATERIALS AND METHODS: The study included mammograms from 1996 to 2001 from the seven mammography registries of the Breast Cancer Surveillance Consortium (BCSC). The authors defined the pre-MQSA period as January 1, 1996-April 27, 1999, and the post-MQSA period as April 28, 1999-December 31, 2001 (2470151 screening and 194199 diagnostic mammograms). Assessment was cross-classified according to management recommendation. Changes in concordance between assessment and recommendation were evaluated by year and by period (before and after MQSA) for computer-linked data and for all data by using Pearson chi(2) test to evaluate differences. Mantel-Haenszel chi(2) test was used to measure change in concordance over time. Each registry and the BCSC Statistical Coordinating Center had a Federal Certificate of Confidentiality and approval from each institution's review board for protection of human subjects to collect and send data to coordinating center and conduct research with these data. Active consent was required at only one site in this HIPAA-compliant study. RESULTS: Concordance increased significantly in the post-MQSA period for Breast Imaging Reporting and Data System categories 3-5 assessments at both screening and diagnostic mammography. The most substantial improvements were in the use of the management recommendation for "additional imaging," which decreased from 41% in 1996 to 15% in 2001 for screening mammograms with an initial assessment of category 4 (P < .001). Recommendation for short-interval follow-up in women with screening mammograms with a category 3 final assessment increased from 51% in 1996 to 76% in 2001 (P < .001). Concordance for diagnostic mammograms assigned category 0 improved from 65% in the pre-MQSA period to 81% in the post-MQSA period (P < .001). CONCLUSION: This analysis demonstrates that over a relatively short period of time, major improvement in radiology reporting has occurred.

Breast Neoplasms↗

Performance benchmarks for screening mammography.

PURPOSE: To retrospectively evaluate the range of performance outcomes of the radiologist in an audit of screening mammography by using a representative sample of U.S. radiologists to allow development of performance benchmarks for screening mammography. MATERIALS AND METHODS: Institutional review board approval was obtained, and study was HIPAA compliant. Informed consent was or was not obtained according to institutional review board guidelines. Data from 188 mammographic facilities and 807 radiologists obtained between 1996 and 2002 were analyzed from six registries from the Breast Cancer Surveillance Consortium (BCSC). Contributed data included demographic information, clinical findings, mammographic interpretation, and biopsy results. Measurements calculated were positive predictive values (PPVs) from screening mammography (PPV(1)), biopsy recommendation (PPV(2)), biopsy performed (PPV(3)), recall rate, cancer detection rate, mean cancer size, and cancer stage. Radiologist performance data are presented as 50th (median), 10th, 25th, 75th, and 90th percentiles and as graphic presentations by using smoothed curves. RESULTS: There were 2 580 151 screening mammographic studies from 1 117 390 women (age range, <30 to >/=80 years). The respective means and ranges of performance outcomes for the middle 50% of radiologists were as follows: recall rate, 9.8% and 6.4%-13.3%; PPV(1), 4.8% and 3.4%-6.2%; and PPV(2), 24.6% and 18.8%-32.0%. Mean cancer detection rate was 4.7 per 1000, and the median [corrected] mean size of invasive cancers was 13 mm. The range of performance outcomes for the middle 80% of radiologists also was presented. CONCLUSION: Community screening mammographic performance measurements of cancer outcomes for the majority of radiologists in the BCSC surpass performance recommendations. Recall rate for almost half of radiologists, however, is higher than the recommended rate.

Adult↗

Association of stellate mammographic pattern with survival in small invasive breast tumors.

OBJECTIVE: We tested whether the stellate mammographic pattern of presentation of small breast tumors is a better indicator of survival than other patterns. MATERIALS AND METHODS: Patients with primary invasive breast cancer diagnosed in 1993-1997 were grouped according to the size of the lesion: 0.1-0.9 cm and 1.0-1.4 cm. Each tumor was placed in one of five mammographic prognostic categories: stellate without calcifications; circular without calcifications; and calcifications with or without tumor mass in a casting, crushed-stone, or other (powdery, punctuate, or round) pattern. To assess reproducibility, a second radiologist gave an independent interpretation in the first 109 cases. Descriptive data were stratified by tumor size, and tests of association were done with an extension of Fisher's exact test. Odds ratios and confidence intervals were computed. Weighted log-rank test and Kaplan-Meier survival curves were used to compare breast cancer survival in the stellate group compared with the other groups. RESULTS: Two hundred one consecutive patients with a median follow-up period of 7.4 years were identified. There were nine breast cancer deaths. The stellate morphologic pattern was most common (91 [45.3%] of 201 cases), yet there was only one breast cancer death in this group (survival rate, 98.9%; 95% confidence interval [CI], 96.7-100%). In the group of stellate lesions smaller than 1.0 cm, 67.6% (25/37) of the tumors were well-differentiated without lymph node metastasis (30 [96.8%] of 31 cases), and there were no deaths. In the group of stellate lesions measuring 1.0-1.4 cm, 66.7% (36/54) of the tumors were well-differentiated with a 19.6% risk of lymph node metastasis, one death, and a survival rate of 98.1% (52/53; 95% CI, 94.4-100%). Circular tumors accounted for 29.9% (60/201) of tumors and 55.6% (5/9) of breast cancer deaths. Casting and crushed-stone microcalcifications were associated with 33.3% (3/9) of disease-specific deaths. A weighted kappa value of 0.89 (CI, 0.83-0.94) indicated very high agreement of pattern assignment. CONCLUSION: Stellate tumors had a significantly better survival prognosis than tumors with other patterns even though there were no differences in treatment. By recognizing these small malignant lesions, trained radiologists may be able to identify tumors that pose negligible risk of breast cancer death.

Aged↗

Diagnostic mammography performance and race: outcomes in Black and White women.

BACKGROUND: A previous study compared the performance (sensitivity, specificity, positive predictive value, and cancer detection rate) of screening mammography in Black and White women. No study, to the authors' knowledge, has evaluated the difference in the performance of diagnostic mammography between Black and White women. METHODS: Univariate analysis was used to evaluate differences in characteristics and cancers between Black and White women. Stratified and adjusted logistic regression analyses were used to test the association of Black and White race with performance measures of diagnostic mammography. RESULTS: The sensitivity of diagnostic mammography was higher (91% vs. 84%) and specificity was lower (86% vs. 90%) among Black women compared with White women. After controlling for age, density, self-reported breast problems, and previous mammography, sensitivity was significantly higher (odds ratio [OR] = 1.82, 95% confidence interval [CI] = 1.22-2.80) and specificity was significantly lower (OR = 0.75, 95% CI = 0.70-0.81) among Black women. The crude cancer detection rate of mammography was higher for Black women (42.6/1000) than for White women (31.0/1000) and Black women had a higher proportion of cancers that were > 2.0 cm (57.4% vs. 46.2%) that were more often poorly differentiated (61.7% vs. 49.3%) and were more often estrogen-receptor and progesterone-receptor negative. CONCLUSIONS: Black women have lower specificity of diagnostic mammography and, consequently, more unnecessary workups than White women. Black women have higher sensitivity of diagnostic mammography, with cancers that are larger and more advanced than White women. Delay in responding to signs and symptoms would explain the size and later stage. However, more research is needed to understand the biologic differences of breast cancer characteristics between Black and White women.

Adult↗

Association between mammography timing and measures of screening performance in the United States.

PURPOSE: To evaluate whether there is an association between the number of months since previous mammography (MSPM) and performance measures (sensitivity, specificity, recall rate, cancer detection rate, and positive predictive value) in women who underwent U.S. community-based screening mammography. MATERIALS AND METHODS: Data from seven registries (Breast Cancer Surveillance Consortium) and mammographic data and cancer outcome in regard to 1 213 754 screening mammographic examinations performed in 680 641 women who were 40-89 years old for the years 1996-2000 were used in this study. These data are submitted annually in a standard format to a central statistical coordinating center that is subject to institutional review board approval, quality control, and confidentiality standards. Performance measures were calculated for first and subsequent screening mammography. For subsequent mammography, performance measures were calculated according to categories of MSPM (9-15, 16-20, 21-27, and >/=28 months). Receiver operating characteristic and multivariable logistic regression analyses were conducted to test the association between the number of MSPM and performance measures. RESULTS: With increasing MSPM in each category from 9-15 to 28 months or more and for first mammographic examinations, respectively, there was increased sensitivity (70.9%, 75.7%, 85.4%, 82.5%, and 88.6%), decreased specificity (93.3%, 92.7%, 91.6%, 91.0%, and 85.9%), increased recall rate (7.0%, 7.6%, 8.8%, 9.4%, and 14.7%), and increased cancer detection rates (3.2, 3.5, 4.5, 4.6, and 6.1 per 1000 mammographic examinations). When the category of 9-15 MSPM was compared with that of 21-27 MSPM, there was a slight increase in positive predictive value from 4.6% to 5.1%. Confidence intervals were narrow and did not overlap. Age affected these associations for all performance measures except sensitivity. CONCLUSION: Performance measures increased as MSPM increased, except for specificity, which decreased. Time between mammograms is an important factor to consider when audits are reviewed or screening performance measures are compared.

Adult↗

Breast cancer yield for screening mammographic examinations with recommendation for short-interval follow-up.

PURPOSE: To compare cancer yield for screening examinations with recommendation for short-interval follow-up after diagnostic imaging work-up versus after screening mammography only. MATERIALS AND METHODS: From January 1996 to December 1999, Breast Imaging Reporting and Data System assessments and recommendations were collected prospectively for 1,171,792 screening examinations in 758,015 women aged 40-89 years at seven mammography registries in Breast Cancer Surveillance Consortium. Registries obtained waiver of signed consent or collected signed consent in accordance with institutional review boards at each location. Diagnosis of invasive cancer or ductal carcinoma in situ within 24 months of screening examination and tumor stage and size for invasive cancer were determined through linkage to pathology database or tumor registry. chi2 test was used to determine significant differences between groups. RESULTS: Overall, 5.2% of first and 1.7% of subsequent screens included recommendation for short-interval follow-up, which was similar to likelihood of recommendation for diagnostic evaluation (first screens, 4.6%; subsequent, 2.6%). Most recommendations for short-interval follow-up were based on screening mammography alone (86.2% of first screens, 77.5% of subsequent). Yield of cancer for screening examinations with probably benign finding (PBF) and recommendation for short-interval follow-up based on screening mammography alone tended to be lower than in those with PBF and recommendation for short-interval follow-up after additional work-up (first screens: 0.54% vs 0.96%, P=.10; subsequent: 1.50% vs 1.73%, P=.26). Proportion of stage II and higher disease tended to be higher for examinations with PBF and recommendation for short-interval follow-up based on screening mammography alone compared with those recommended for short-interval follow-up after additional work-up (first screens: 34.7% vs 24.4%, P=.43; subsequent: 27.5% vs 19.2%, P=.13). CONCLUSION: Many first screening examinations include recommendation for short-interval follow-up based on screening mammography alone. Cancer yield for these examinations is low and is lower than that with diagnostic work-up prior to short-interval follow-up recommendation. Absence of diagnostic work-up prior to short-interval follow-up recommendation may result in periodic surveillance of a high proportion of benign lesions.

Adult↗

Performance benchmarks for diagnostic mammography.

PURPOSE: To evaluate a range of performance parameters pertinent to the comprehensive auditing of diagnostic mammography examinations, and to derive performance benchmarks therefrom, by pooling data collected from large numbers of patients and radiologists that are likely to be representative of mammography practice in the United States. MATERIALS AND METHODS: Institutional review board approval was met, informed consent was not required, and this study was Health Insurance Portability and Accountability Act compliant. Six mammography registries contributed data to the Breast Cancer Surveillance Consortium (BCSC), providing patient demographic and clinical information, mammogram interpretation data, and biopsy results from defined population-based catchment areas. The study involved 151 mammography facilities and 646 interpreting radiologists. The study population included women 18 years of age or older who underwent at least one diagnostic mammography examination between 1996 and 2001. Collected data were used to derive mean performance parameter values, including abnormal interpretation rate, positive predictive value (for abnormal interpretation, biopsy recommended, and biopsy performed), cancer diagnosis rate, invasive cancer size, and the percentages of minimal cancers, axillary node-negative invasive cancers, and stage 0 and I cancers. Additional benchmarks were derived for these performance parameters, including 10th, 25th, 50th (median), 75th, and 90th percentile values. RESULTS: The study involved 332,926 diagnostic mammography examinations. Mean performance parameter values were abnormal interpretation rate, 8.0%; positive predictive value for abnormal interpretation, 31.4%; positive predictive value for biopsy recommended, 31.5%; positive predictive value for biopsy performed, 39.5%; cancer diagnosis rate, 25.3 per 1000 examinations; invasive cancer size, 20.2 mm; percentage of minimal cancers, 42.0%; percentage of axillary node-negative invasive cancers, 73.6%; and percentage of stage 0 and I cancers, 62.4%. CONCLUSION: The presented BCSC outcomes data and performance benchmarks may be used by mammography facilities and individual radiologists to evaluate their own performance for diagnostic mammography as determined by means of periodic comprehensive audits.

Adult↗

Biennial versus annual mammography and the risk of late-stage breast cancer.

BACKGROUND: Mammography screening may reduce breast cancer mortality by detecting cancers at an earlier stage. However, certain questions remain, including the ideal interval between mammograms. METHODS: We conducted an observational study using information collected by seven mammography registries across the United States to investigate whether women diagnosed with breast cancer after having screening mammograms separated by a 2-year interval (n = 2440) are more likely to be diagnosed with late-stage disease (positive lymph nodes or metastases) than women diagnosed with breast cancer after having screening mammograms separated by a 1-year interval (n = 5400). Analyses were stratified by age and breast density to clarify whether groups that have the poorest mammography sensitivity (i.e., women under age 50 years and those with mammographically dense breasts) would benefit most from annual screening. The subjects were women diagnosed with breast cancer between 1996 and 2001 who were 40-89 years old at their index mammographic examination (i.e., the most recent screen at or before breast cancer diagnosis). Data were analyzed by logistic regression, adjusting for race, ethnicity, family history of breast cancer, and mammography registry. RESULTS: Among women age 40-49 years at the index mammogram, those with a 2-year screening interval were more likely to have late-stage disease at diagnosis than those with a 1-year screening interval (28% versus 21%; odds ratio [OR] = 1.35, 95% confidence interval [CI] = 1.01 to 1.81). There was no increase in late-stage disease for women 50 years or older with a 2-year versus a 1-year screening interval (women age 50-59 years at index mammogram: OR = 0.97, 95% CI = 0.75 to 1.25; women age 60-69 years at index mammogram: OR = 0.99, 95% CI = 0.72 to 1.35; women age 70 years or older at index mammogram: OR = 0.88, 95% CI = 0.64 to 1.19). There was no indication that women with dense breasts would benefit more from a 1-year versus 2-year screening interval than women with fatty breasts. CONCLUSION: These findings may be useful for policy decisions about appropriate screening intervals and for use in statistical models that estimate the costs and benefits of mammography by age and screening interval.

Adult↗

Effect of breast augmentation on the accuracy of mammography and cancer characteristics.

CONTEXT: Breast augmentation is not associated with an increased risk of breast cancer; however, implants may interfere with the detection of breast cancer thereby delaying cancer diagnosis in women with augmentation. OBJECTIVE: To determine whether mammography accuracy and tumor characteristics are different for women with and without augmentation. DESIGN, SETTING, AND PARTICIPANTS: A prospective cohort of 137 women with augmentation and 685 women without augmentation diagnosed with breast cancer between January 1, 1995, and October 15, 2002, matched (1:5) by age, race/ethnicity, previous mammography screening, and mammography registry, and 10 533 women with augmentation and 974 915 women without augmentation and without breast cancer among 7 mammography registries in Denver, Colo; Lebanon, NH; Albuquerque, NM; Chapel Hill, NC; San Francisco, Calif; Seattle, Wash; and Burlington, Vt. MAIN OUTCOME MEASURES: Comparison between women with and without augmentation of mammography performance measures and cancer characteristics, including invasive carcinoma or ductal carcinoma in situ, tumor stage, nodal status, size, grade, and estrogen-receptor status. RESULTS: Among asymptomatic women, the sensitivity of screening mammography based on the final assessment was lower in women with breast augmentation vs women without (45.0% [95% confidence interval [CI], 29.3%-61.5%] vs 66.8% [95% CI, 60.4%-72.8%]; P =.008), and specificity was slightly higher in women with augmentation (97.7% [95% CI, 97.4%-98.0%] vs 96.7% [95% CI, 96.6%-96.7%]; P<.001). Among symptomatic women, both sensitivity and specificity were lower for women with augmentation compared with women without but these differences were not significant. Tumors were of similar stage, size, estrogen-receptor status, and nodal status but tended to be lower grade (P =.052) for women with breast augmentation vs without. CONCLUSIONS: Breast augmentation decreases the sensitivity of screening mammography among asymptomatic women but does not increase the false-positive rate. Despite the lower accuracy of mammography in women with augmentation, the prognostic characteristics of tumors are not influenced by augmentation.

Adult↗

Screening mammography performance and cancer detection among black women and white women in community practice.

BACKGROUND: Despite improvement in mammography screening attendance, black women continue to have poorer prognosis at diagnosis than white woman. Data from the Carolina Mammography Registry were used to evaluate whether there may be differences in mammography performance or detected cancers when comparing black women with white women who are screened by mammography. METHODS: Prospectively collected data from community-based mammography facilities on 468,484 screening mammograms (79,397 in black women and 389,087 in white women) were included for study. Mammograms were linked to a pathology data base for identification of cancers. Sensitivity, specificity, positive predictive value, and cancer detection rates were compared between black women and white women. Logistic regression methods were used to control for covariates associated with performance characteristics. Differences in cancer characteristics were compared between black women and white women using chi-square statistics. RESULTS: Screening mammography performance results for black women compared with white women were as follows: sensitivity, odds ratio (OR) = 1.07 (95% confidence interval [95% CI], 0.83-1.39); specificity, OR = 1.02 (95% CI, 0.98-1.06); and positive predictive value, OR = 1.07 (95% CI, 0.94-1.23). Among women with no previous screening, black women had a larger proportion of invasive tumors that measured > or = 2 cm (38% vs. 26%; P = 0.04). The cancer detection rate was highest among black women who reported symptoms at screening (13.9 per 1000 black women vs. 7.9 per 1000 white women). Invasive cancers in black women were poorer grade (P = 0.001), and more often had negative estrogen receptor status and progesterone receptor status (P < 0.001). CONCLUSIONS: Overall, screening mammography performed equally well in black women and white women controlling for age, breast density, and time since previous mammogram. Black women who reported symptoms had larger and higher grade tumors compared with white women. Educational efforts need to be strengthened to encourage black women to react sooner to symptoms, so that the tumors detected will be smaller and black women will have a better prognosis when they appear for mammography.

Adult↗

Individual and combined effects of age, breast density, and hormone replacement therapy use on the accuracy of screening mammography.

BACKGROUND: The relationships among breast density, age, and use of hormone replacement therapy (HRT) in breast cancer detection have not been fully evaluated. OBJECTIVE: To determine how breast density, age, and use of HRT individually and in combination affect the accuracy of screening mammography. DESIGN: Prospective cohort study. SETTING: 7 population-based mammography registries in North Carolina; New Mexico; New Hampshire; Vermont; Colorado; Seattle, Washington; and San Francisco, California. PARTICIPANTS: 329 495 women 40 to 89 years of age who had 463 372 screening mammograms from 1996 to 1998; 2223 women received a diagnosis of breast cancer. MEASUREMENTS: Breast density, age, HRT use, rate of breast cancer occurrence, and sensitivity and specificity of screening mammography. RESULTS: Adjusted sensitivity ranged from 62.9% in women with extremely dense breasts to 87.0% in women with almost entirely fatty breasts; adjusted sensitivity increased with age from 68.6% in women 40 to 44 years of age to 83.3% in women 80 to 89 years of age. Adjusted specificity increased from 89.1% in women with extremely dense breasts to 96.9% in women with almost entirely fatty breasts. In women who did not use HRT, adjusted specificity increased from 91.4% in women 40 to 44 years of age to 94.4% in women 80 to 89 years of age. In women who used HRT, adjusted specificity was about 91.7% for all ages. CONCLUSIONS: Mammographic breast density and age are important predictors of the accuracy of screening mammography. Although HRT use is not an independent predictor of accuracy, it probably affects accuracy by increasing breast density.

Adipose Tissue↗

Mammography surveillance following breast cancer.

BACKGROUND: To describe when women diagnosed with breast cancer return for their first mammography, and to identify factors predictive of women returning for mammographic surveillance. METHODS: Women who underwent mammography at facilities participating in the National Cancer Institute's Breast Cancer Surveillance Consortium (BCSC) during 1996 and who were subsequently diagnosed with ductal carcinoma in situ or invasive breast cancer were included in this study. Data from seven mammography registries were linked to population-based cancer and pathology registries. Kaplan-Meier curves were used to depict the number of months from the breast cancer diagnosis to the first mammogram within the defined follow-up period. Demographic, disease and treatment variables were included in univariate and multivariate analyses to identify factors predictive of women returning for mammography. RESULTS: Of the 2503 women diagnosed with breast cancer, 78.1% returned for mammography examination between 7 and 30 months following the diagnosis. Mammography facilities indicated that 66.8% of mammography examinations were classified as screening. Multivariate analyses found that women were most likely to undergo surveillance mammography if they were diagnosed at ages 60-69 with Stage 0, I or II breast cancer and had received radiation therapy in addition to surgery. CONCLUSIONS: While the majority of women return for mammographic surveillance following breast cancer, some important subgroups of women at higher risk for recurrence are less likely to return. Research is needed to determine why some women are not undergoing mammography surveillance after a breast cancer diagnosis and whether surveillance increases the chance of detecting tumors with a good prognosis.

Adult↗

Detection of ductal carcinoma in situ in women undergoing screening mammography.

BACKGROUND: With the large number of women having mammography-an estimated 28.4 million U.S. women aged 40 years and older in 1998-the percentage of cancers detected as ductal carcinoma in situ (DCIS), which has an uncertain prognosis, has increased. We pooled data from seven regional mammography registries to determine the percentage of mammographically detected cancers that are DCIS and the rate of DCIS per 1000 mammograms. METHODS: We analyzed data on 653 833 mammograms from 540 738 women between 40 and 84 years of age who underwent screening mammography at facilities participating in the National Cancer Institute's Breast Cancer Surveillance Consortium (BCSC) throughout 1996 and 1997. Mammography results were linked to population-based cancer and pathology registries. We calculated the percentage of screen-detected breast cancers that were DCIS, the rate of screen-detected DCIS per 1000 mammograms by age and by previous mammography status, and the sensitivity of screening mammography. Statistical tests were two-sided. RESULTS: A total of 3266 cases of breast cancer were identified, 591 DCIS and 2675 invasive breast cancer. The percentage of screen-detected breast cancers that were DCIS decreased with age (from 28.2% [95% confidence interval (CI) = 23.9% to 32.5%] for women aged 40-49 years to 16.0% [95% CI = 13.3% to 18.7%] for women aged 70-84 years). However, the rate of screen-detected DCIS cases per 1000 mammograms increased with age (from 0.56 [95% CI = 0.41 to 0.70] for women aged 40-49 years to 1.07 [95% CI = 0.87 to 1.27] for women aged 70-84 years). Sensitivity of screening mammography in all age groups combined was higher for detecting DCIS (86.0% [95% CI = 83.2% to 88.8%]) than it was for detecting invasive breast cancer (75.1% [95% CI = 73.5% to 76.8%]). CONCLUSIONS: Overall, approximately 1 in every 1300 screening mammography examinations leads to a diagnosis of DCIS. Given uncertainty about the natural history of DCIS, the clinical significance of screen-detected DCIS needs further investigation.

Adult↗

Performance of diagnostic mammography for women with signs or symptoms of breast cancer.

BACKGROUND: The performance of diagnostic mammography for women with signs or symptoms of breast cancer has not been well studied. We evaluated whether age, breast density, self-reported breast lump, and previous mammography influence the performance of diagnostic mammography. METHODS: From January 1996 through March 1998, prospective diagnostic mammography data from women aged 25-89 years with no previous breast cancer were linked to cancer outcomes data in six mammography registries participating in the Breast Cancer Surveillance Consortium. We used the final mammographic assessment at the end of the imaging work-up to determine abnormal mammographic examination rate, positive predictive value (PPV), sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve. We used age, breast density, prior mammogram, and self-reported breast lump jointly as predictors of performance. All statistical tests were two-sided. RESULTS: Of 41 427 diagnostic mammograms, 6279 (15.2%) were judged abnormal. The overall PPV was 21.8%, sensitivity was 85.8%, and specificity was 87.7%. Multivariate analysis showed that sensitivity and specificity generally declined as breast density increased (P =.007 and P<.001, respectively), that previous mammography decreased sensitivity (odds ratio [OR] = 0.52, 95% confidence interval [CI] = 0.36 to 0.74; P<.001) but increased specificity (OR = 1.43, 95% CI = 1.31 to 1.57; P<.001), and that a self-reported breast lump increased sensitivity (OR = 1.64, 95% CI = 1.13 to 2.38; P =.013) but decreased specificity (OR = 0.54, 95% CI = 0.49 to 0.59; P<.001). ROC analysis showed that higher breast density and previous mammography were negatively related to accuracy (P<.001 for both). CONCLUSIONS: Diagnostic mammography in women with signs or symptoms of breast cancer shows higher sensitivity and lower specificity than screening mammography does. Higher breast density and previous mammographic examination appear to impair performance.

Adult↗