Vermont Breast Cancer Surveillance System Research Articles

Long-term Mammography Screening Trends and Predictors of Return to Screening after the COVID-19 Pandemic: Results from a Statewide Registry.

Purpose To evaluate long-term trends in mammography screening rates and identify sociodemographic and breast cancer risk characteristics associated with return to screening after the COVID-19 pandemic. Materials and Methods In this retrospective study, statewide screening mammography data of 222 384 female individuals aged 40 years or older (mean age, 58.8 years ± 11.7 [SD]) from the Vermont Breast Cancer Surveillance System were evaluated to generate descriptive statistics and Joinpoint models to characterize screening patterns during 2000-2022. Log-binomial regression models estimated associations of sociodemographic and risk characteristics with post-COVID-19 pandemic return to screening. Results The proportion of female individuals in Vermont aged 50-74 years with a screening mammogram obtained in the previous 2 years declined from a prepandemic level of 61.3% (95% CI: 61.1%, 61.6%) in 2019 to 56.0% (95% CI: 55.7%, 56.3%) in 2021 before rebounding to 60.7% (95% CI: 60.4%, 61.0%) in 2022. Screening adherence in 2022 remained substantially lower than that observed during the 2007-2010 apex of screening adherence (66.1%-67.0%). Joinpoint models estimated an annual percent change of -1.1% (95% CI: -1.5%, -0.8%) during 2010-2022. Among the cohort of 95 644 individuals screened during January 2018-March 2020, the probability of returning to screening during 2020-2022 varied by age (eg, risk ratio [RR] = 0.94 [95% CI: 0.93, 0.95] for age 40-44 vs age 60-64 years), race and ethnicity (RR = 0.84 [95% CI: 0.78, 0.90] for Black vs White individuals), education (RR = 0.84 [95% CI: 0.81, 0.86] for less than high school degree vs college degree), and by 5-year breast cancer risk (RR = 1.06 [95% CI: 1.04, 1.08] for very high vs average risk). Conclusion Despite a rebound to near prepandemic levels, Vermont mammography screening rates have steadily declined since 2010, with certain sociodemographic groups less likely to return to screening after the pandemic. Keywords: Mammography, Breast, Health Policy and Practice, Neoplasms-Primary, Epidemiology, Screening Supplemental material is available for this article. © RSNA, 2024.

Detection Rates for Benign and Malignant Diagnoses on Breast Cancer Screening With Digital Breast Tomosynthesis in a Statewide Mammography Registry Study.

The objective of our study was to determine whether detection rates of specific benign and malignant diagnoses differ for breast cancer screening with digital breast tomosynthesis (DBT) versus full-field digital mammography (FFDM) alone. We analyzed observational data from the Vermont Breast Cancer Surveillance System, including 86,349 DBT screening examinations and 97,378 FFDM screening examinations performed at eight radiology facilities in Vermont that adopted DBT screening during 2012-2016. We determined the most severe diagnosis made within 6 months after positive screening examinations. Multivariable-adjusted logistic regression was used to compare detection rates for specific diagnoses on DBT versus FFDM. Compared with FFDM, DBT had a lower recall rate (adjusted odds ratio [OR], 0.81; 95% CI, 0.77-0.85) but comparable biopsy rate (OR = 1.05; 95% CI, 0.93-1.17), benign biopsy rate (OR = 1.12; 95% CI, 0.97-1.29), and cancer detection rate (OR = 0.94; 95% CI, 0.78-1.14). Among benign diagnoses, DBT and FFDM had comparable detection rates for nonproliferative lesions (OR = 1.19; 95% CI, 0.92-1.53), fibroepithelial proliferations (OR = 1.24; 95% CI, 0.85-1.81), proliferative lesions without atypia (OR = 1.13; 95% CI, 0.90-1.42), atypical lesions (OR = 0.77; 95% CI, 0.43-1.38), and lobular carcinoma in situ (LCIS) (OR = 0.92; 95% CI, 0.53-1.61). Among malignant diagnoses, DBT and FFDM had comparable detection rates for ductal carcinoma in situ (OR = 1.05; 95% CI, 0.70-1.57) and invasive breast cancer (OR = 0.92; 95% CI, 0.74-1.13), with no statistically significant differences in detection of invasive ductal carcinoma (OR = 0.83; 95% CI, 0.66-1.06), invasive lobular carcinoma (OR = 1.11; 95% CI, 0.59-2.07), or invasive mixed ductal-lobular carcinoma (OR = 1.49; 95% CI, 0.65-3.39). Compared with FFDM, breast cancer screening with DBT has a lower recall rate while detecting a similar distribution of benign and malignant diagnoses.

Time-varying risks of second events following a DCIS diagnosis in the population-based Vermont DCIS cohort.

Long-term disease-free survival patterns following surgical, radiation, and endocrine therapy treatments for ductal carcinoma in situ (DCIS) are not well characterized in general US practice. We identified 1252 women diagnosed with DCIS in Vermont during 1994-2012 using data from the Vermont Breast Cancer Surveillance System, a statewide registry of breast imaging and pathology records. Poisson regression and Cox regression with time-varying hazards were used to evaluate disease-free survival among self-selected treatment groups. With 7.8years median follow-up, 192 cases experienced a second breast cancer diagnosis. For women treated with breast-conserving surgery (BCS) alone, the annual rate of second events decreased from 3.1% (95% CI 2.2-4.2%) during follow-up years 1-5 to 1.7% (95% CI 0.7-3.5%) after 10years. In contrast, the annual rate of second events among women treated with BCS plus adjuvant radiation therapy increased from 1.8% (95% CI 1.1-2.6%) during years 1-5 to 2.8% (95% CI 1.6-4.7%) after 10years (P < 0.05 for difference in trend compared to BCS alone). Annual rates of second events also increased over time among women treated with BCS plus adjuvant radiation and endocrine therapy (P = 0.01 for difference in trend compared to BCS alone). The rate of contralateral events increased after 10years for all groups with adjuvant treatments. The rate of second events did not vary over time among women who underwent ipsilateral mastectomy (P = 0.62). Long-term risk of a second event after DCIS varies over time in a manner dependent on initial treatment.

The impact of mammographic screening on the surgical management of breast cancer.

Mammographic screening has been shown to result in downward stage migration, reflected by smaller tumor sizes and less extensive nodal involvement. National guidelines restrict screening recommendations in women age 40-49. The purpose of this study is to evaluate the specific impact of mammographic screening patterns on the surgical management of breast cancer in women aged 40-49. The study is a population-based retrospective review of the Vermont Breast Cancer Surveillance System of women aged 40-49 with a diagnosis of breast cancer. Tumor stage and related characteristics at the time of diagnosis, as well as the type of surgical intervention performed were recorded for women presenting with screen-detected versus non-screen-detected breast cancer. Screen-detected breast cancers in women aged 40-49 were associated with a greater incidence of DCIS, smaller invasive tumor size, fewer cases of positive nodes, and higher rates of breast conservation compared to non-screened women presenting with symptomatic disease. Mammographic screening is associated with less aggressive surgical treatment of breast cancer including higher rates of breast conservation. The observed changes in surgical management should factor into individual decision-making regarding screening mammography. J. Surg. Oncol. 2016;113:496-500. © 2016 Wiley Periodicals, Inc.

A prospective study of the use and effects of screening mammography in women aged 70 and older.

To prospectively examine how age and comorbidity affect screening mammography use, cancer detection, and overall survival. Prospective, with median follow-up of 10.2 years. A population-based cohort of Vermont women with data in the Vermont Breast Cancer Surveillance System. Women aged 70 and older with no history of breast cancer (N = 20,697). Rates of screening, diagnostic procedure use, and breast cancer diagnosis were examined according to age and comorbidity. The effect of breast cancer on overall survival was assessed in relation to detection mode, tumor characteristics, and treatment. Screening declined 9% per year after age 70 and 18% with each unit increase in comorbidity score, with corresponding increases in clinically detected breast cancer. Invasive cancer was associated with greater overall mortality (screen detected: hazard ratio (HR) = 1.22, 95% confidence interval (CI) = 1.07-1.40; clinically detected: HR = 1.68, 95% CI = 1.43-1.96). The latter HR reflects a much greater absolute risk of death for women in a population with high baseline mortality. Use of breast-conserving surgery as the only treatment for Stage I cancer increased markedly with age and was associated with shorter overall survival than radiation or mastectomy (relative risk = 2.23, 95% CI = 1.42-3.47). Lower screening mammography use by older women is associated with more clinically detected breast cancers, which are associated with poorer survival. Treatment received for early-stage cancer influences the effect of screening on survival.

Changes in breast cancer risk distribution among Vermont women using screening mammography.

Screening mammography utilization in Vermont has declined since 2009 during a time of changing screening guidelines and increased interest in personalized screening regimens. This study evaluates whether the breast cancer risk distribution of the state's screened population changed during the observed decline. We examined the breast cancer risk distribution among screened women between 2001 and 2012 using data from the Vermont Breast Cancer Surveillance System. We estimated each screened woman's 5-year risk of breast cancer using the Breast Cancer Surveillance Consortium risk calculator. Annual screening counts by risk group were normalized and age-adjusted to the Vermont female population by direct standardization. The normalized rate of low-risk (5-year breast cancer risk of <1%) women screened increased 8.3% per year (95% confidence interval [CI] = 4.8 to 11.9) between 2003 and 2008 and then declined by -5.4% per year (95% CI = -8.1 to -2.6) until 2012. When stratified by age group, the rate of low-risk women screened declined -4.4% per year (95% CI = -8.8 to 0.1; not statistically significant) for ages 40 to 49 years and declined a statistically significant -7.1% per year (95% CI = -12.1 to -2.0) for ages 50 to 74 years during 2008 to 2012. These declines represented the bulk of overall decreases in screening after 2008, with rates for women categorized in higher risk levels generally exhibiting small annual changes. The observed decline in women screened in Vermont in recent years is largely attributable to reductions in screening visits by women who are at low risk of developing breast cancer.

Changes in the Breast Cancer Risk Distribution among Women Utilizing Screening Mammography in Vermont Between 2001 and 2012

Abstract We previously reported a decline in overall breast cancer screening rates in Vermont following 2009. During this period, there has been debate regarding the role of patient context in decisions about when and how often to get screened, as well as increased interest in risk- based screening to optimize the balance between the potential benefits and harms of screening. The purpose of the current study was to evaluate whether the breast cancer risk distribution of the screened population in Vermont has changed during the observed decline in utilization rates. We examined the distribution of breast cancer risk among the screened population in Vermont from 2001 to 2012 using cross-sectional data from the statewide Vermont Breast Cancer Surveillance System. We employed the Breast Cancer Surveillance Consortium risk model to estimate each individual's risk of developing breast cancer within 5 years according to age, breast density, race/ethnicity, family history of breast cancer, and biopsy history. Among women ages 40 to 74 who received screening mammograms, the absolute number of visits dropped by 4,257, from 54,415 to 50,158 (−7.3%; 95% CI: −7.5, −7.1) between 2009 and 2012. Concurrently, the number of screened women who were estimated to be at low risk of developing breast cancer decreased by 4,240 (95% CI: 3,907, 4,573), representing the bulk of the overall decrease. There was no significant change in the aggregate number of women estimated to be at higher risk (−17 women; 95% CI: −350, 316). The outsized proportion of the decline attributed to women at low estimated risk held across younger and older age groups: among women ages 40 to 49, the absolute number screened dropped by 3,337, with 2,495 (95% CI: 2,389, 2,601) reflected by declines among women at low risk; among women ages 50 to 74, the absolute number screened dropped by only 920, however this value reflects a decrease of 1,763 (95% CI: 1,519, 2,007) for the low risk category, and gains totaling 843 (95% CI: 599, 1,087) among higher risk categories. We conclude that the observed decline in women screened in Vermont since 2009 is largely attributable to reductions in visits by women who are estimated to be at low risk of developing breast cancer, and that this trend generally holds across age groups.

Reproducibility of BI-RADS breast density measures among community radiologists: a prospective cohort study.

Using data from the Vermont Breast Cancer Surveillance System (VBCSS), we studied the reproducibility of Breast Imaging Reporting and Data System (BI-RADS) breast density among community radiologists interpreting mammograms in a cohort of 11,755 postmenopausal women. Radiologists interpreting two or more film-screen screening or bilateral diagnostic mammograms for the same woman within a 3- to 24-month period during 1996-2006 were eligible. We observed moderate-to-substantial overall intra-rater agreement for use of BI-RADS breast density in clinical practice, with an overall intra-radiologist percent agreement of 77.2% (95% confidence interval (CI), 74.5-79.5%), an overall simple kappa of 0.58 (95% CI, 0.55-0.61), and an overall weighted kappa of 0.70 (95% CI, 0.68-0.73). Agreement exhibited by individual radiologists varied widely, with intra-radiologist percent agreement ranging from 62.1% to 87.4% and simple kappa ranging from 0.19 to 0.69 across individual radiologists. Our findings underscore the need for additional evaluation of the BI-RADS breast density categorization system in clinical practice.

Accuracy of Screening Mammography in Older Women

The objective of our study was to determine the accuracy and cancer detection rate of screening mammography in women as they age. Using data from the Vermont Breast Cancer Surveillance System (1996-2006), we calculated the sensitivity, specificity, positive predictive value, negative predictive value, and cancer detection rate by decade of age for 403,448 mammograms of 96,193 women 50-101 years old. Confounding variables were assessed using logistic regression analysis. The sensitivity of screening mammography increased from 77.3% for the 50- to 59-year-old group to 93.8% for the 90- to 101-year-old group (p = 0.015). Specificity increased from 98.7% to 98.8% at age 50-59 compared with age 90-101 (p < 0.001), respectively. The cancer detection rate increased from 3.7 cases per 1000 mammograms at age 50-59 to 14.4 cases per 1000 mammograms at age 90-101 (p < 0.001). The prevalence of breast cancer increased from 4.8% to 15.4% across age groups (p < 0.001) as did the positive predictive value from 22.2% to 55.6% (p <0.001). There was no evidence of confounding by body mass index, breast density, or other factors. Tumors were more likely to be small, hormone receptor-positive, and more invasive as women aged. Accuracy parameters were all associated with age without evidence of confounding by regression analysis. Screening mammography is more accurate in older women than in younger women, suggesting that it may be of value in assessing women in all age groups. These data do not address the impact of mammography screening on mortality or breast cancer outcomes.

Variability in the quality of pathology reporting of margin status following breast cancer surgery.

Accurately determining margin status is important for breast cancer treatment. The College of American Pathologists (CAP) developed guidelines to standardize reporting of margin status. The aim of this study is to determine statewide concordance with CAP breast cancer reporting guidelines for margin status. The Vermont Breast Cancer Surveillance System (VBCSS) tracks mammography-related services provided to all women treated for breast cancer at hospitals in Vermont. These data include accompanying pathology reports, which were analyzed for descriptions of margin status. The CAP protocols have both requirements and recommendations for margin status reporting. Reports were "minimally compliant" if they adhered to the requirements stated in the CAP protocols or "maximally compliant" if they included the recommended protocols in addition to those required. There were 2,016 reports that met the inclusion criteria. A total of 71.1% were minimally compliant and 37.3% were maximally compliant with the CAP guideline standards. There was a statistically significant rise in compliant reports, with minimally compliant reports increasing from 55.7% in 1998 to 79.3% in 2006, and maximally compliant reports rising from 4.7% in 1998 to 53.7% in 2006 (χ(2) trend test, P < 0.001) for both cohorts. Reporting of margin status in breast-conserving surgery varies widely. There is a significant rise in guideline compliance with margin status reporting from 1998 to 2006; however, overall compliance remains suboptimal. This study provides evidence to support the need for quality improvement measures in the implementation of CAP guidelines for reporting margin status following breast-conserving surgery.

Traditionality and Cancer Screening Practices Among American Indian Women in Vermont

The study purpose was to examine the relationship between cancer screening and traditionality, using a culturally specific survey instrument. American Indian (AI) women were randomly selected from the Vermont Breast Cancer Surveillance System (VBCSS), a statewide mammography database. The 13 items that assessed traditionality examined identity, cultural beliefs, customs, and health practices. The sample of 115 was predominately married, educated, middle class, insured, and rural. Significant associations were found between traditionality and past mammography and clinical breast examination (CBE) behavior, as well as future mammography intention. Results suggest that traditionality scales can be useful for identifying differences in screening behavior, with further testing of traditionality items with other AI women recommended. International implications of the study findings are also addressed.

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

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. 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. 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. 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.