Predicting Biopsy Outcome After Mammography: What Is the Likelihood the Patient Has Invasive or In Situ Breast Cancer?

BACKGROUND

As many as 1,000,000 breast biopsies are performed annually in the United States. Although substantial effort has been devoted to estimating breast cancer risk, there have been no studies to predict outcome in women undergoing breast biopsy.

METHODS

A population-based study was undertaken to develop and test models for predicting the probability of invasive breast cancer and/or ductal carcinoma-in-situ in 7670 women undergoing breast biopsy after mammography. Logistical prediction models were developed by using data from 6129 randomly selected women and tested with data from the remaining women.

RESULTS

The overall cancer prevalence among women undergoing biopsy was 22.4%. Prevalence in women with mammograms highly suggestive of malignancy (category 5) was 84.6%, with minimal variation in individual cancer probabilities due to age. A total of 24.6% of women with suspicious mammograms (category 4) had cancer, but individual probability estimates ranged from .01 to .86, depending on age, presence of a lump, previous biopsy, menopausal status, and use of postmenopausal hormone therapy. These variables also influenced biopsy outcome in women with other mammography assessments (categories 0-3), but the overall prevalence was lower (8.6%), and estimated probabilities ranged from .01 to .45. When cancer was present, the probability of invasive disease was influenced by mammogram assessment category, absence of mammogram calcifications, and presence of a lump.

CONCLUSIONS

The probabilities of invasive cancer and ductal carcinoma-in-situ in women undergoing biopsy can be more accurately predicted by using clinical characteristics in addition to mammography findings. This information could potentially influence decisions regarding immediate biopsy or continued surveillance.

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.

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.

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.

Moving in between mammography: screening decisions of American Indian women in Vermont

Breast cancer is a leading cause of cancer death among American Indian women, with mammography screening rates below the national average for this population. A grounded theory study, conducted with Vermont American Indian women, explicated factors that influence mammography decision making. The authors examined mammography decision making across the breast cancer screening continuum: women with a history of consistent annual mammograms, women who were under users or nonusers of mammography, and women who were breast cancer survivors. The generated theory, Moving in Between Mammography, describes the decision-making process and factors that influenced women's participation in routine mammography screening. Specific influencing factors addressed include Connecting to Nativeness, Taking Care of Self, Financing Health Care, and (Mis)Trusting the Health Care System. Implications and directions for future research are addressed.

A prospective study of breast cancer risk using routine mammographic breast density measurements

Mammographic breast density is a major risk factor for breast cancer but estimates of the relative risk associated with differing density patterns have varied widely. It is also unclear how menopausal status influences this association and to what extent the effects of density are due to its correlation with other risk factors. Most recent investigations of breast density have been case-control studies, which provide indirect estimates of relative risk. We have prospectively followed 61,844 women for an average of 3.1 years to directly estimate risk among women in the four mammographic breast density categories defined by the American College of Radiology's Breast Imaging Reporting and Data System (BI-RADS). The study was population-based and used density assessments routinely made by community radiologists. Cox regression was used to obtain age-adjusted relative risk estimates and to control for other risk factors. Risk increased with density and the risk associated with extremely dense breasts, relative to entirely fatty breasts, was 4.6 (95% confidence interval, 1.7-12.6) for premenopausal women and 3.9 (95% confidence interval, 2.6-5.8) for postmenopausal women. Estimates for pre- and postmenopausal women did not differ significantly. Although breast density was significantly related to body mass index, age at first childbirth, and postmenopausal hormone use (P < 0.001), adjustment for these variables only slightly altered the relative risk estimates. Our results correspond well to those from case-control studies using more quantitative measures of mammographic breast density and suggest that routine Breast Imaging Reporting and Data System density measurements may be useful in models for assessing breast cancer risk in individual women.

A Prospective Study of Breast Cancer Risk Using Routine Mammographic Breast Density Measurements

Mammographic breast density is a major risk factor for breast cancer but estimates of the relative risk associated with differing density patterns have varied widely. It is also unclear how menopausal status influences this association and to what extent the effects of density are due to its correlation with other risk factors. Most recent investigations of breast density have been case-control studies, which provide indirect estimates of relative risk. We have prospectively followed 61,844 women for an average of 3.1 years to directly estimate risk among women in the four mammographic breast density categories defined by the American College of Radiology's Breast Imaging Reporting and Data System (BI-RADS). The study was population-based and used density assessments routinely made by community radiologists. Cox regression was used to obtain age-adjusted relative risk estimates and to control for other risk factors. Risk increased with density and the risk associated with extremely dense breasts, relative to entirely fatty breasts, was 4.6 (95% confidence interval, 1.7–12.6) for premenopausal women and 3.9 (95% confidence interval, 2.6–5.8) for postmenopausal women. Estimates for pre- and postmenopausal women did not differ significantly. Although breast density was significantly related to body mass index, age at first childbirth, and postmenopausal hormone use (P &lt; 0.001), adjustment for these variables only slightly altered the relative risk estimates. Our results correspond well to those from case-control studies using more quantitative measures of mammographic breast density and suggest that routine Breast Imaging Reporting and Data System density measurements may be useful in models for assessing breast cancer risk in individual women.

Patient perceptions of breast biopsy procedures for screen-detected lesions

OBJECTIVE

This study was undertaken to compare patient perceptions of 2 common image-guided breast biopsy procedures on 3 main outcomes: decision making about which procedure to undergo, its convenience, and its side effects.

METHODS

Women who had either an excisional or ultrasound-guided core needle breast biopsy in 1997 for a screen-detected lesion had telephone interviews 1 to 3 months after the biopsy. Bivariate associations were tested by using chi(2) and t test statistics. Mulitvariate analyses were used to control for effects of demographic characteristics.

RESULTS

Most women (66%) could not remember being offered a choice of procedures, and of those who did have a choice, a higher proportion had an excisional biopsy. Only 2% reported being told the cost of the biopsy procedure. Women who had an excisional biopsy compared with those who had undergone a core needle biopsy reported statistically more hours and days off from work and reported more side effects 1 to 3 days after the biopsy (P<.05). Associations between side effects and type of biopsy procedure were unchanged when adjustment was made for demographic characteristics.

CONCLUSION

Women who had the ultrasound-guided needle biopsy reported significantly fewer side effects and needed less time off from work. When a suspicious lesion is noticed on a screening mammogram, it is important that women and their physicians discuss the benefits and risks of the various biopsy procedures before deciding how to proceed, allowing for informed choice.

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.

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.

Prognostic Characteristics of Breast Cancer Among Postmenopausal Hormone Users in a Screened Population

Purpose: We determined the risk of breast cancer and tumor characteristics among current postmenopausal hormone therapy users compared with nonusers, by duration of use.

Methods: From January 1996 to December 2000, data were collected prospectively on 374,465 postmenopausal women aged 50 to 79 years who underwent screening mammography. We calculated the relative risk (RR) of breast cancer (invasive or ductal carcinoma-in-situ) and type of breast cancer within 12 months of postmenopausal therapy use among current hormone users with a uterus (proxy for estrogen and progestin use) and without a uterus (proxy for estrogen use), compared with nonusers.

Results: Compared with nonusers, women using estrogen and progestin for ≥ 5 years were at increased risk of breast tumors of stage 0 or I (RR, 1.51; 95% CI, 1.37 to 1.66), stage II or higher (RR, 1.46; 95% CI, 1.30 to 1.63), size ≤ 20 mm (RR, 1.59; 95% CI, 1.43 to 1.76), size greater than 20 mm (RR, 1.24; 95% CI, 1.09 to 1.42), grade 1 or 2 (RR, 1.60; 95% CI, 1.44 to 1.77), grade 3 or 4 (RR, 1.54; 95% CI, 1.37 to 1.73), and estrogen receptor-positive (RR, 1.72; 95% CI, 1.55 to 1.90). Estrogen-only users were slightly more likely to have estrogen receptor-positive breast cancer compared with nonusers (RR, 1.14; 95% CI, 1.06 to 1.23).

Conclusion: Use of estrogen and progestin postmenopausal hormone therapy for five years or more increased the likelihood of developing breast cancer, including both tumors with favorable prognostic features and tumors with unfavorable prognostic features.

Factors Associated with Arm Swelling after Breast Cancer Surgery

PURPOSE

As life expectancy improves for women with breast cancer, more women will be living with symptoms of lymphedema. This study reports the incidence of arm or hand swelling and associated risk factors in women with invasive breast cancer following surgery.

METHODS

Data were obtained from baseline and follow-up interviews of women with invasive breast cancer (n = 145), and mammography and pathology records. The Kaplan-Meier method was used to estimate the probability of developing arm or hand swelling over time. Univariate and multivariate logistic regression analyses were conducted to identify risk factors for arm or hand swelling.

RESULTS

Of women in this study, 38% self-reported arm or hand swelling. There was a significantly increased risk of arm swelling if women were under 50 years of age, had axillary node dissection, received chemotherapy, worked outside the home, and had a high household income. There was no association of body weight with swelling. A significantly decreased risk of arm swelling was found in women who were on treatment for high blood pressure. After adjustment for nodal dissection, only age had a significant independent effect.

CONCLUSIONS

Our study highlights two important areas of future research that could reduce the incidence of lymphedema. There is a need to better understand the role that treatment for high blood pressure may play in protecting women from arm edema. Second, the potential effect of weight as a modifiable lymphedema risk factor needs to be studied in more detail in light of the conflicting results of different studies.

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.

Effect of false-positive mammograms on return for subsequent screening mammography

There has been concern that false-positive mammograms may deter women from future screening mammograms. We sought to determine whether false-positive mammograms affected follow-up for rescreening. We studied a cohort of 41,844 women in the Vermont Mammography Registry. We measured the proportion of women returning for the next screening mammogram for 30 months following an initial screening mammogram, and compared rates of follow-up screening at 18 and 30 months in women with false-positive and true-negative initial mammograms. We adjusted for potential confounders using multivariable logistic regression models. Of the 2469 women aged 50 years or older with false-positive mammograms, 67.2% (n = 1660) returned at 18 months for rescreening, compared with 63.9% (16,948/26,521) of the women with true-negative mammograms (P = 0.001). Similarly, 86.8% (2143/2469) of the women with false-positive mammograms returned at 30 months for rescreening, compared with 84.7% (22,466/26,521) of the women with true-negative mammograms (P = 0.005). After adjusting for age, use of hormone replacement therapy, prior mammography, prior false-positive mammography, and education, women with false-positive mammograms were more likely to return at 18 months (odds ratio [OR] = 1.40; 95% confidence interval [CI]: 1.30 to 1.51) and at 30 months (OR = 1.30; 95% CI: 1.18 to 1.44). Despite previous concerns, false-positive screening mammograms did not discourage women from returning for subsequent screening mammography. However, other deleterious effects of false-positive results still warrant improvements in the accuracy of breast cancer screening.

Surviving breast cancer: the role of complementary therapies

Early detection and efficacious treatment have prolonged the lives of women diagnosed with breast cancer. Although many of these women have survived more than 5 years, there is minimal knowledge of their use of complementary and alternative medical (CAM) treatments. A qualitative focus group study was conducted with 66 breast cancer survivors, ranging in age from 32 to 85 years, with time since diagnosis 2 to 28 years. This article will discuss specific reasons breast cancer survivors reported for using CAM, the ways in which breast cancer survivors blended these therapies with conventional Western medicine, and health care providers' roles in supporting breast cancer survivors' use of CAM approaches.

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.

Evaluation of a community breast screening promotion program

BACKGROUND

This study reports results of a controlled evaluation of a comprehensive community breast screening promotion program. This program promoted increased use of mammography, clinical breast examination, and breast self-examination through community organization, physician training, and public education.

METHODS

The program was conducted in one of three matched Florida study areas, with before and after assessment of breast screening behaviors, beliefs, and perceptions of women ages 40 and older. Baseline measures in 1990 were obtained by combining telephone and household survey data; follow-up measures using similar combined data were conducted with 4,096 women in 1997.

RESULTS

. There was no evidence that the breast screening promotion program achieved higher levels of screening among women ages 40 and older in the program area. Mammography use and supportive beliefs and perceptions of mammography increased in all three study areas between 1990 and 1997.

CONCLUSIONS

Among factors that may have reduced the differential impact of the program were public attention to breast cancer screening in the late 1980s throughout the U.S., effects of managed care, and limited penetration of a key program component. While the program was well received and served the community, its impact was overwhelmed by temporal trends observed in this study.

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.

Increased mammography use and its impact on earlier breast cancer detection in Vermont, 1975-1999

BACKGROUND

A trend toward earlier breast carcinoma detection in the United States has been attributed to screening mammography, although direct evidence linking this trend to the increased use of mammography in a general population is lacking. This study examined the effects of mammography on tumor size and axillary lymph node metastasis in Vermont over 25 years.

METHODS

Pathology and mammography data from 3499 Vermont women who were diagnosed with invasive breast carcinoma during 1975-1984, 1989-1990, and 1995-1999 were compared. Logistic regression analysis was used to estimate the effects of age, mammography use, and period on the odds of a tumor < or = 2 cm and the odds of negative lymph nodes.

RESULTS

The proportion of breast tumors that were detected by screening mammography increased from 2% during 1974-1984 to 36% during 1995-1999 (P < 0.001), and these tumors were more likely to measure < or = 2 cm than tumors that were detected by other methods. Among women age > 50 years, the odds ratio (OR) was 4.5, with a 95% confidence interval (95% CI) of 3.5-6.4. The effect was smaller in younger women (OR, 1.8; 95% CI, 1.1-3.0). Mammographic detection increased the odds of negative lymph nodes by a similar amount in both age groups, although women age > 50 years were more likely to have negative lymph nodes than younger women (OR, 1.3; 95% CI, 1.1-1.6). Tumor size and lymph node metastasis also were related to the number of mammograms and to the mammographic interval.

CONCLUSIONS

Most of the trend toward earlier detection in Vermont was due to mammography. Mammography had a lesser effect on tumor size among younger women, which may be related to less frequent screening, although its effect on lymph node metastasis was not age dependent. Women age < 50 years were more likely to have positive lymph nodes, independent of the method of detection or the frequency of mammography.

Concordance of breast imaging reporting and data system assessments and management recommendations in screening mammography

PURPOSE

To examine how frequently Breast Imaging Reporting and Data System (BI-RADS) mammographic screening assessments were associated with expected clinical management recommendations.

MATERIALS AND METHODS

Seven Breast Cancer Surveillance Consortium mammography registries recorded screening assessments and recommendations in 1997 to identify the proportion of women in each BI-RADS category. The first screening assessment for a woman without cancer or a prior mammogram within 9 months was associated with its independently recorded recommendation.

RESULTS

Among 292,795 women, screening assessments included 269,022 (91.9%) with a "negative" or "benign finding," and 267,103 (99.3%) of these women were recommended for normal interval follow-up. Among 11,861 (4.1%) women with screening assessments of "probably benign finding," 4,782 (40.3%) were recommended for short interval follow-up as expected on the basis of the BI-RADS, but a high proportion (36.9%) were recommended for additional imaging. Among 1,625 (0.6%) women with "suspicious abnormality," most were recommended for biopsy (48.7%) or clinical examination and/or surgical consult (9.0%), but many were recommended for additional imaging (38.7%). Among 243 (0.1%) women with screening assessments "highly suggestive of malignancy," a majority were recommended for biopsy (73.3%) or clinical examination and/or surgical consult (18.1%) consistent with BI-RADS, but some were recommended for additional imaging (6.6%).

CONCLUSION

BI-RADS assessments and management recommendations are consistent for negative and benign assessments, but inconsistencies were found in assessments and recommendations for mammographic abnormalities.

Use of the American College of Radiology BI-RADS to report on the mammographic evaluation of women with signs and symptoms of breast disease

PURPOSE

To examine whether mammographic assessments and recommendations are linked as expected, based on the Breast Imaging Reporting and Data System (BI-RADS), for the evaluation of women with signs and symptoms of breast disease.

MATERIALS AND METHODS

Eight mammography registries from the Breast Cancer Surveillance Consortium contributed mammographic data from 1996 through 1997 for women 25 years of age or older, with signs or symptoms of breast cancer. The association of assessments and recommendations and the relationship of self-reported symptoms to assessments are described.

RESULTS

A total of 51,673 diagnostic mammograms were included in the analyses and the expected management recommendation was provided 85%-90% of the time for mammograms classified as assessment categories 1, 2, 4, or 5. Category 3 ("probably benign finding") had the most variability in associated management recommendations, with only 40% (2,998 of 7,423) of cases associated with the recommendation for short interval follow-up. Of the 1,648 category 0 mammograms ("needs additional imaging") that did not have a final assessment, 64% were recommended for additional imaging, while another 20% of the cases were recommended for either a consultation or biopsy. The number of women who reported a lump as a symptom decreased with age but was associated with higher BI-RADS assessments.

CONCLUSION

BI-RADS assessment categories were generally used as intended for all categories but 0 and 3. Additional education about the use of these categories may be warranted. The inconsistencies between assessment category and management recommendations may present difficulties in conducting outcome audits.

Identifying women at risk for inherited breast cancer using a mammography registry

BACKGROUND

Women at risk for inherited breast cancer have been identified for intervention studies through newly diagnosed relatives or from volunteers with a family history. This pilot study tested the use of a mammography registry to identify women at risk.

METHOD

Fifty women with first-degree relatives diagnosed as having breast cancer before age 45 were randomly selected from the Vermont Breast Cancer Surveillance System. Thirty-three women (66%) completed a phone interview that included a three-generation family pedigree of breast and ovarian cancers.

RESULTS

Fifty-one percent of the women were at higher risk for inherited breast cancer based on the family history. Eighteen percent of the first-degree relatives' breast cancers were pathologically confirmed.

CONCLUSION

Mammography registries that collect similar family history data may be used to identify women at risk for inherited breast cancer. Many intervention studies would require improved methods to obtain pathologic confirmation.

Current medicolegal and confidentiality issues in large, multicenter research programs

The convenience of fast computers and the Internet have encouraged large collaborative research efforts by allowing transfers of data from multiple sites to a single data repository; however, standards for managing data security are needed to protect the confidentiality of participants. Through Dartmouth Medical School, in 1996-1998, the authors conducted a medicolegal analysis of federal laws, state statutes, and institutional policies in eight states and three different types of health care settings, which are part of a breast cancer surveillance consortium contributing data electronically to a centralized data repository. They learned that a variety of state and federal laws are available to protect confidentiality of professional and lay research participants. The strongest protection available is the Federal Certificate of Confidentiality, which supersedes state statutory protection, has been tested in court, and extends protection from forced disclosure (in litigation) to health care providers as well as patients. This paper describes the careful planning necessary to ensure adequate legal protection and data security, which must include a comprehensive understanding of state and federal protections applicable to medical research. Researchers must also develop rules or guidelines to ensure appropriate collection, use, and sharing of data. Finally, systems for the storage of both paper and electronic records must be as secure as possible.

The association of increased weight, body mass index, and tissue density with the risk of breast carcinoma in Vermont

BACKGROUND

Etiologic studies of breast carcinoma have indicated that weight, body mass index (BMI), and breast tissue density are important determinants of a woman's risk for the disease. This study looked at the independent effects of these risk factors.

METHODS

Data from the Vermont Breast Cancer Surveillance System (VBCSS), collected between May 1996 and November 1997, were used to identify 529 breast carcinoma cases with no prior history of the disease. Each case was matched to four randomly chosen women of the same age who had mammograms during the same time period and had no biopsy-confirmed breast carcinoma. Logistic regression was used to assess the effects of weight, BMI, and breast tissue density on breast carcinoma risk for pre- and postmenopausal women.

RESULTS

Weight and BMI were found to be significantly associated with postmenopausal breast carcinoma after adjustment for breast density, and vice versa. The density-adjusted odds ratio for women weighing over 81 kg, relative to women weighing under 63 kg, was 2.1, with a 95% confidence interval (CI) of 1.3-3.2. Relative to women with breasts consisting entirely of fat, the weight-adjusted odds ratios for women with heterogeneously dense and extremely dense breasts were 2.3 (CI: 1.3-4.3) and 4.5 (CI: 1.9-10.6), respectively.

CONCLUSIONS

Among postmenopausal Vermont women, weight, BMI, and breast density were independently associated with breast carcinoma risk. Because breast density and weight or BMI are inversely related, estimates of their independent effects should be used when evaluating a woman's risk for breast carcinoma.

The role of health professionals in a community-based program to help women quit smoking

BACKGROUND

Health professionals are credible sources of smoking cessation advice. This study describes changes in health professionals' reported provision of smoking cessation counseling activities for women during a community health education project that took place in two intervention counties (I) and compares these to reports from health professionals in two similar comparison counties (C).

METHODS

Specific smoking cessation activities reported by physicians (I n = 73, C n = 73), dentists (I n = 51, C n = 46), dental hygienists (I n = 38, C n = 44), family planning and WIC (Special Supplemental Food Program for Women, Infants and Children) counselors (I n = 14 C n = 16), and community mental health counselors (I n = 57, C n = 23) were assessed by mailed surveys at baseline, after 4 years of countywide interventions, and 2 years later.

RESULTS

Compared with health professionals in the comparison counties, significant increases in smoking cessation training (P < 0.01) and in reported referral of women to stop smoking groups, support groups, and one-to-one support were noted for physicians, family planning, and WIC counselors (P < 0.001); in training and referral to stop smoking groups and support groups by dentists and dental hygienists (P < 0.05); and in referral to support groups by community mental health counselors (P < 0.05). Significant increases in setting quit dates (P < 0.05) and providing self-help materials (P < 0.01) were also noted for family planning and WIC counselors. These effects were no longer demonstrable 2 years after external support for the countywide interventions was withdrawn.

CONCLUSIONS

We suggest that an important aspect of facilitating consistent smoking cessation advice and counseling from health professionals in the future will be the provision of a broader range of regularly available smoking cessation support systems within communities than is generally available at this time in the United States.