Diagnosis of second breast cancer events after initial diagnosis of early stage breast cancer

Contrast-enhanced mammography for surveillance in women with a personal history of breast cancer

PURPOSE

Women with a personal history of breast cancer have an increased risk of subsequent breast malignancy and may benefit from more sensitive surveillance than conventional mammography (MG). We previously reported outcomes for first surveillance episode using contrast-enhanced mammography (CEM), demonstrating higher sensitivity and comparable specificity to MG. We now report CEM performance for subsequent surveillance.

METHODS

A retrospective study of 1,190 women in an Australian hospital setting undergoing annual surveillance following initial surveillance CEM between June 2016 and December 2022. Outcome measures were recall rate, cancer detection rate, contribution of contrast to recalls, false positive rate, interval cancer rate and characteristics of surveillance detected and interval cancers.

RESULTS

2,592 incident surveillance episodes were analysed, of which 93% involved contrast-based imaging. Of 116 (4.5%) recall episodes, 40/116 (34%) recalls were malignant (27 invasive; 13 ductal carcinoma in situ), totalling 15.4 cancers per 1000 surveillance episodes. 55/116 (47%) recalls were contrast-directed including 17/40 (43%) true positive recalls. Tumour features were similar for contrast-directed recalls and other diagnoses. 8/9 (89%) of contrast-directed invasive recalls were Grade 2-3, and 5/9 (56%) were triple negative breast cancers. There were two symptomatic interval cancers (0.8 per 1000 surveillance episodes, program sensitivity 96%).

CONCLUSION

Routine use of CEM in surveillance of women with PHBC led to an increase in the detection of clinically significant malignant lesions, with a low interval cancer rate compared to previous published series. Compared to mammographic surveillance, contrast-enhanced mammography increases the sensitivity of surveillance programs for women with PHBC.

Predicting five-year interval second breast cancer risk in women with prior breast cancer

BACKGROUND

Annual surveillance mammography is recommended for women with a personal history of breast cancer. Risk prediction models that estimate mammography failures such as interval second breast cancers could help to tailor surveillance imaging regimens to women's individual risk profiles.

METHODS

In a cohort of women with a history of breast cancer receiving surveillance mammography in the Breast Cancer Surveillance Consortium in 1996-2019, we used Least Absolute Shrinkage and Selection Operator (LASSO)-penalized regression to estimate the probability of an interval second cancer (invasive cancer or ductal carcinoma in situ) in the 1 year after a negative surveillance mammogram. Based on predicted risks from this one-year risk model, we generated cumulative risks of an interval second cancer for the five-year period after each mammogram. Model performance was evaluated using cross-validation in the overall cohort and within race and ethnicity strata.

RESULTS

In 173 290 surveillance mammograms, we observed 496 interval cancers. One-year risk models were well-calibrated (expected/observed ratio = 1.00) with good accuracy (area under the receiver operating characteristic curve = 0.64). Model performance was similar across race and ethnicity groups. The median five-year cumulative risk was 1.20% (interquartile range 0.93%-1.63%). Median five-year risks were highest in women who were under age 40 or pre- or perimenopausal at diagnosis and those with estrogen receptor-negative primary breast cancers.

CONCLUSIONS

Our risk model identified women at high risk of interval second breast cancers who may benefit from additional surveillance imaging modalities. Risk models should be evaluated to determine if risk-guided supplemental surveillance imaging improves early detection and decreases surveillance failures.

Semiannual Breast US or MRI Screening in Patients with a Personal History of Breast Cancer

Background The wide variability of screening imaging use in patients with a personal history of breast cancer (PHBC) warrants investigation of its comparative clinical effectiveness. While more intensive screening with US or MRI at an interval of less than 1 year could increase early-stage breast cancer detection, its benefit has not been established. Purpose To investigate the outcomes of semiannual multimodality screening in patients with PHBC. Materials and Methods An academic medical center database was retrospectively searched for patients diagnosed with breast cancer between January 2015 and June 2018 who had undergone annual mammography with either semiannual incidence US or MRI screening from July 2019 to December 2019 and three subsequent semiannual screenings over a 2-year period. The primary outcome was second breast cancers diagnosed during follow-up. Examination-level cancer detection and interval cancer rates were calculated. Screening performances were compared with χ2 or Fisher exact tests or a logistic model with generalized estimating equations. Results Our final cohort included 2758 asymptomatic women (median age, 53 years; range, 20-84 years). Among 5615 US and 1807 MRI examinations, 18 breast cancers were detected after negative findings on a prior semiannual incidence US screening examination; 44% (eight of 18) were stage 0 (three detected with MRI; five, with US), and 39% (seven of 18) were stage I (three detected with MRI; four, with US). MRI had a cancer detection rate up to 17.1 per 1000 examinations (eight of 467; 95% CI: 8.7, 33.4), and the overall cancer detection rates of US and MRI were 1.8 (10 of 5615; 95% CI: 1.0, 3.3) and 4.4 (eight of 1807; 95% CI: 2.2, 8.8) per 1000 examinations, respectively (P = .11). Conclusion Supplemental semiannual US or MRI screening depicted second breast cancers after negative findings at prior semiannual incidence US examination in patients with PHBC. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Berg in this issue.

Performance of Statistical and Machine Learning Risk Prediction Models for Surveillance Benefits and Failures in Breast Cancer Survivors

BACKGROUND

Machine learning (ML) approaches facilitate risk prediction model development using high-dimensional predictors and higher-order interactions at the cost of model interpretability and transparency. We compared the relative predictive performance of statistical and ML models to guide modeling strategy selection for surveillance mammography outcomes in women with a personal history of breast cancer (PHBC).

METHODS

We cross-validated seven risk prediction models for two surveillance outcomes, failure (breast cancer within 12 months of a negative surveillance mammogram) and benefit (surveillance-detected breast cancer). We included 9,447 mammograms (495 failures, 1,414 benefits, and 7,538 nonevents) from years 1996 to 2017 using a 1:4 matched case-control samples of women with PHBC in the Breast Cancer Surveillance Consortium. We assessed model performance of conventional regression, regularized regressions (LASSO and elastic-net), and ML methods (random forests and gradient boosting machines) by evaluating their calibration and, among well-calibrated models, comparing the area under the receiver operating characteristic curve (AUC) and 95% confidence intervals (CI).

RESULTS

LASSO and elastic-net consistently provided well-calibrated predicted risks for surveillance failure and benefit. The AUCs of LASSO and elastic-net were both 0.63 (95% CI, 0.60-0.66) for surveillance failure and 0.66 (95% CI, 0.64-0.68) for surveillance benefit, the highest among well-calibrated models.

CONCLUSIONS

For predicting breast cancer surveillance mammography outcomes, regularized regression outperformed other modeling approaches and balanced the trade-off between model flexibility and interpretability.

IMPACT

Regularized regression may be preferred for developing risk prediction models in other contexts with rare outcomes, similar training sample sizes, and low-dimensional features.

Contrast enhanced mammography in breast cancer surveillance

PURPOSE

Mammography (MG) is the standard imaging in surveillance of women with a personal history of breast cancer or DCIS (PHBC), supplemented with ultrasound. Contrast Enhanced Mammography (CEM) has higher sensitivity than MG and US. We report the performance of CEM compared with MG ± US.

METHODS

A retrospective study of patients undergoing their first surveillance CEM in an Australian hospital setting between June 2006 and October 2020. Cases where a patient was recalled for assessment were identified, recording radiology, pathology and treatment details. Blinded re-reading of recalled cases was performed to determine the contribution of contrast. Use of surveillance US across the board was assessed for the period.

RESULTS

73/1191 (6.1%) patients were recalled. 35 (48%) were true positives (TP), with 26 invasive cancers and 9 cases of DCIS, while 38 (52%) were false positive (FP) with a positive predictive value (PPV) 47.9%. 32/73 were recalled due to MG findings, while 41/73 were only recalled due to Contrast. 14/73 had 'minimal signs' with a lesion identifiable on MG with knowledge of the contrast finding, while 27/73 were visible only with contrast. 41% (17/41) recalled due to contrast were TP. Contrast-only TPs were found with low and high mammographic density (MD). Screening breast US reduced by 55% in the year after CEM was implemented.

CONCLUSION

Compared to MG, CEM as a single surveillance modality for those with PHBC has higher sensitivity and comparable specificity, identifying additional malignant lesions that are clinically significant. Investigation of interval cancer and subsequent round outcomes is warranted.

Mammographic calcifications undergoing percutaneous biopsy: outcome in women with and without a personal history of breast cancer

PURPOSE

To compare the positive predictive values (PPVs) of BI-RADS categories used to assess pure mammographic calcifications in women with and without a previous history of breast cancer (PHBC).

MATERIALS AND METHODS

In this retrospective study, all consecutive pure mammographic calcifications (n = 320) undergoing a stereotactic biopsy between 2016 and 2018 were identified. Mammograms were evaluated in consensus by two radiologists according to BI-RADS and blinded to patient history and pathology results. Final pathologic results were used as the standard of reference. PPV of BI-RADS categories were compared between the two groups. Data were evaluated using standard statistics, Mann-Whitney U tests and Chi-square tests.

RESULTS

Two hundred sixty-eight patients (274 lesions, median age 54 years, inter-quartile range, 50-65 years) with a PHBC (n = 46) and without a PHBC (n = 222) were included. Overall PPVs were the following: BI-RADS 2, 0% (0 of 56); BI-RADS 3, 9.1% (1 of 11); BI-RADS 4a, 16.2% (6 of 37); BI-RADS 4b, 37.5% (48 of 128); BI-RADS 4c, 47.3% (18 of 38) and BI-RADS 5, 100% (4 of 4). The PPV of BI-RADS categories was similar in patients with and without a PHBC (P = .715). Calcifications were more often malignant in patients with a PHBC older than 10 years (47.3%, 9 of 19) compared to 1-2 years (25%, 1 of 4), 2-5 years (20%, 2 of 10) and 5-10 years (0%, of 13) from the first breast cancer (P = .005).

CONCLUSION

PPV of mammographic calcifications is similar in women with or without PHBC when BI-RADS classification is strictly applied. A higher risk of malignancy was observed in patients with a PHBC longer than 10 years.

Imaging Surveillance Options for Individuals With a Personal History of Breast Cancer: AJR Expert Panel Narrative Review

Annual surveillance mammography is recommended for breast cancer survivors on the basis of observational studies and meta-analyses showing reduced breast cancer mortality and improved quality of life. However, breast cancer survivors are at higher risk of subsequent breast cancer and have a fourfold increased risk of interval breast cancers compared with individuals without a personal history of breast cancer. Supplemental surveillance modalities offer increased cancer detection compared with mammography alone, but utilization is variable, and benefits must be balanced with possible harms of false-positive findings. In this review, we describe the current state of mammographic surveillance, summarize evidence for supplemental surveillance in breast cancer survivors, and explore a risk-based approach to selecting surveillance imaging strategies. Further research identifying predictors associated with increased risk of interval second breast cancers and development of validated risk prediction tools may help physicians and patients weigh the benefits and harms of surveillance breast imaging and decide on a personalized approach to surveillance for improved breast cancer outcomes.

Biological Mechanisms and Therapeutic Opportunities in Mammographic Density and Breast Cancer Risk

Mammographic density is an important risk factor for breast cancer; women with extremely dense breasts have a four to six fold increased risk of breast cancer compared to women with mostly fatty breasts, when matched with age and body mass index. High mammographic density is characterised by high proportions of stroma, containing fibroblasts, collagen and immune cells that suggest a pro-tumour inflammatory microenvironment. However, the biological mechanisms that drive increased mammographic density and the associated increased risk of breast cancer are not yet understood. Inflammatory factors such as monocyte chemotactic protein 1, peroxidase enzymes, transforming growth factor beta, and tumour necrosis factor alpha have been implicated in breast development as well as breast cancer risk, and also influence functions of stromal fibroblasts. Here, the current knowledge and understanding of the underlying biological mechanisms that lead to high mammographic density and the associated increased risk of breast cancer are reviewed, with particular consideration to potential immune factors that may contribute to this process.

Digital Mammography and Breast Tomosynthesis Performance in Women with a Personal History of Breast Cancer, 2007-2016

Background Since 2007, digital mammography and digital breast tomosynthesis (DBT) replaced screen-film mammography. Whether these technologic advances have improved diagnostic performance has, to the knowledge of the authors, not yet been established. Purpose To evaluate the performance and outcomes of surveillance mammography (digital mammography and DBT) performed from 2007 to 2016 in women with a personal history of breast cancer and compare with data from 1996 to 2007 and the performance of digital mammography screening benchmarks. Materials and Methods In this observational cohort study, five Breast Cancer Surveillance Consortium registries provided prospectively collected mammography data linked with tumor registry and pathologic outcomes. This study identified asymptomatic women with American Joint Committee on Cancer anatomic stages 0-III primary breast cancer who underwent surveillance mammography from 2007 to 2016. The primary outcome was a second breast cancer diagnosis within 1 year of mammography. Performance measures included the recall rate, cancer detection rate, interval cancer rate, positive predictive value of biopsy recommendation, sensitivity, and specificity. Results Among 32 331 women who underwent 117 971 surveillance mammographic examinations (112 269 digital mammographic examinations and 5702 DBT examinations), the mean age at initial diagnosis was 59 years ± 12 (standard deviation). Of 1418 second breast cancers diagnosed, 998 were surveillance-detected cancers and 420 were interval cancers. The recall rate was 8.8% (10 365 of 117 971; 95% CI: 8.6%, 9.0%), the cancer detection rate was 8.5 per 1000 examinations (998 of 117 971; 95% CI: 8.0, 9.0), the interval cancer rate was 3.6 per 1000 examinations (420 of 117 971; 95% CI: 3.2, 3.9), the positive predictive value of biopsy recommendation was 31.0% (998 of 3220; 95% CI: 29.4%, 32.7%), the sensitivity was 70.4% (998 of 1418; 95% CI: 67.9%, 72.7%), and the specificity was 98.1% (114 331 of 116 553; 95% CI: 98.0%, 98.2%). Compared with previously published studies, interval cancer rate was comparable with rates from 1996 to 2007 in women with a personal history of breast cancer and was higher than the published digital mammography screening benchmarks. Conclusion In transitioning from screen-film to digital mammography and digital breast tomosynthesis, surveillance mammography performance demonstrated minimal improvement over time and remained inferior to the performance of screening mammography benchmarks. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Moy and Gao in this issue.

Optimal Screening in Breast Cancer Survivors With Dense Breasts on Mammography

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.

Risk factors and prediction of second primary cancer in primary female non-metastatic breast cancer survivors

This study aimed to investigate the risk factors of second primary cancer among female breast cancer (BC) survivors, with emphasis on the prediction of the individual risk conditioned on the patient's characteristics. We identified 208,474 BC patients diagnosed between 2004 and 2010 from the Surveillance, Epidemiology and End Results (SEER) database. Subdistribution proportional hazard model and competing-risk nomogram were used to explore the risk factors of second primary BC and non-BC, and to predict the 5- and 10-year probabilities of second primary BC. Model performance was evaluated via calibration curves and decision curve analysis. The overall 3-, 5-, and 10-year cumulative incidences for second primary BC were 0.9%, 1.6% and 4.4%, and for second primary non-BC were 2.3%, 3.9%, and 7.8%, respectively. Age over 70 years at diagnosis, black race, tumor size over 2 cm, negative hormone receptor, mixed histology, localized tumor, lumpectomy alone, and surgeries plus radiotherapy were significantly associated with increased risk of second BC. The risk of second non-BC was only related to age, race and tumor size. The proposed risk model as well as its nomogram was clinically beneficial to identify patients at high risk of developing second primary breast cancer.

Surveillance Magnetic Resonance Imaging in Detecting the Second Breast Cancer in Women With a Personal History of Breast Cancer

OBJECTIVE

The objective of this study was to evaluate the diagnostic performance of magnetic resonance imaging (MRI) in detecting the secondary breast cancer among women with a personal history of the lesion.

MATERIALS AND METHODS

We retrospectively reviewed breast MRI examinations performed between 2007 and 2011. A total of 798 women with a history of breast cancer were included in the study. Cancer detection rate, positive predictive value (PPV), recall rate, sensitivity, and specificity were assed. Cancer detection rate was stratified by interval after surgery of the primary breast cancer. Also, we derived 1 comparison group from the women for comparing the performance of x-ray mammography, ultrasound, and MRI in detecting the second breast cancer.

RESULTS

Of the 798 patients, 47 of the 49 secondary breast carcinomas were detected by MRI. The sensitivity and specificity of MRI in detecting the secondary lesions were 95.9% and 96.3%, respectively. The recall rate was 9.5%, and the PPV was 61.8%. Cancer detection rate of MRI examinations performed at more than 36 months after initial surgery was significantly higher than that at 36 months or less after initial surgery (13.7% vs 3.6, P < 0.001). In comparison group, the sensitivity and specificity of MRI, mammography, and ultrasound were 96.7% and 96.1%, 48.4% and 93.9%, and 77.4% and 96.1%, respectively.

CONCLUSIONS

Surveillance MRI for women with a personal history of breast cancer has high sensitivity in finding the secondary malignancies with a reasonable recall rate and PPV.

Patterns of Breast Imaging Use Among Women with a Personal History of Breast Cancer

BACKGROUND

National patterns of breast imaging in women with a personal history of breast cancer (PHBC) are unknown making evaluation of annual surveillance recommendations a challenge.

OBJECTIVE

To describe variation in use of mammography and breast magnetic resonance imaging (MRI) examinations beginning 6 months after diagnosis among women with PHBC in US community practice. We report on the breast imaging indication, imaging intervals, and time since breast cancer diagnosis by examination type.

DESIGN

Longitudinal study using cross-sectional data.

SETTING

Breast Cancer Surveillance Consortium breast imaging facilities.

PARTICIPANTS

19,955 women diagnosed between 2005 and 2012 with AJCC stage 0-III incident breast cancer who had 69,386 mammograms and 3,553 breast MRI examinations from January 2005 to September 2013; median follow-up of 37.6 months (interquartile range, 22.1-60.7).

MAIN MEASURES

Breast imaging indication, imaging intervals, and time since breast cancer diagnosis by examination type.

KEY RESULTS

Among women with a PHBC who received breast imaging, 89.4% underwent mammography alone, 0.8% MRI alone, and 10.3% had both mammography and MRI. About half of mammograms and MRIs were indicated for surveillance vs. diagnostic, with an increase in the proportion of surveillance exams as time from diagnosis increased (mammograms, 45.7% at 1 year to 72.2% after 5 years; MRIs, 54.8% at 1 year to 78.6% after 5 years). In the first post-diagnosis period, 32.8% of women had > 2 breast imaging examinations and of these, 65.8% were less than 6 months apart. During the first 5-year post-diagnosis, the frequency of examinations per year decreased and the interval between examinations shifted towards annual examinations.

CONCLUSION

In women with a PHBC who received post-diagnosis imaging, a third underwent multiple breast imaging examinations per year during the first 2-year post-diagnosis despite recommendations for annual exams. As time since diagnosis increases, imaging indication shifts from diagnostic to surveillance.

Surveillance Breast MRI and Mammography: Comparison in Women with a Personal History of Breast Cancer

Background There is lack of consensus regarding the use of breast MRI for routine surveillance for second breast cancer events in women with a personal history of breast cancer. Purpose To compare performance of surveillance mammography with breast MRI. Materials and Methods This observational cohort study used prospectively collected data and included 13 266 women age 18 years and older (mean age, 60 years ± 13) with stage 0-III breast cancer who underwent 33 938 mammographic examinations and 2506 breast MRI examinations from 2005 to 2012 in the Breast Cancer Surveillance Consortium. Women were categorized into two groups: mammography alone (n = 11 745) or breast MRI (n = 1521). Performance measures were calculated by using end-of-day assessment and occurrence of second breast cancer events within 1 year of imaging. Logistic regression was used to compare performance for breast MRI versus mammography alone, adjusting for women, examination, and primary breast cancer characteristics. Analysis was conducted on a per-examination basis. Results Breast MRI was associated with younger age at diagnosis, chemotherapy, and higher education and income. Raw performance measures for breast MRI versus mammography were as follows, respectively: cancer detection rates, 10.8 (95% confidence interval [CI]: 6.7, 14.8) versus 8.2 (95% CI: 7.3, 9.2) per 1000 examinations; sensitivity, 61.4% (27 of 44; 95% CI: 46.5%, 76.2%) versus 70.3% (279 of 397; 95% CI: 65.8%, 74.8%); and biopsy rate, 10.1% (253 of 2506; 95% CI: 8.9%, 11.3%) versus 4.0% (1343 of 33 938; 95% CI: 3.7%, 4.2%). In multivariable models, breast MRI was associated with higher biopsy rate (odds ratio [OR], 2.2; 95% CI: 1.9, 2.7; P < .001) and cancer detection rate (OR, 1.7; 95% CI: 1.1, 2.7; P = .03) than mammography alone. However, there were no differences in sensitivity (OR, 1.1; 95% CI: 0.4, 2.9; P = .84) or interval cancer rate (OR, 1.1; 95% CI: 0.6, 2.2; P = .70). Conclusion Comparison of the performance of surveillance breast MRI with mammography must account for patient characteristics. Whereas breast MRI leads to higher biopsy and cancer detection rates, there were no significant differences in sensitivity or interval cancers compared with mammography. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Newell in this issue.

Mortality After Breast Cancer Among Survivors of Childhood Cancer: A Report From the Childhood Cancer Survivor Study

PURPOSE

Female survivors of childhood cancer have a high risk of subsequent breast cancer. We describe the ensuing risk for mortality and additional breast cancers.

PATIENTS AND METHODS

Female participants in the Childhood Cancer Survivor Study, a cohort of 5-year survivors of cancer diagnosed between 1970 and 1986 before age 21 years, and subsequently diagnosed with breast cancer (n = 274; median age at breast cancer diagnosis, 38 years; range, 20 to 58 years) were matched to a control group (n = 1,095) with de novo breast cancer. Hazard ratios (HRs) and 95% CIs were estimated from cause-specific proportional hazards models.

RESULTS

Ninety-two childhood cancer survivors died, 49 as a result of breast cancer. Overall survival after breast cancer was 73% by 10 years. Subsequent risk of death as a result of any cause was higher among childhood cancer survivors than among controls (HR, 2.2; 95% CI, 1.7 to 3.0) and remained elevated after adjusting for breast cancer treatment (HR, 2.4; 95% CI, 1.7 to 3.2). Although breast cancer-specific mortality was modestly elevated among childhood cancer survivors (HR, 1.3; 95% CI, 0.9 to 2.0), survivors were five times more likely to die as a result of other health-related causes, including other subsequent malignant neoplasms and cardiovascular or pulmonary disease (HR, 5.5; 95% CI, 3.4 to 9.0). The cumulative incidence of a second asynchronous breast cancer also was elevated significantly compared with controls (P < .001).

CONCLUSION

Mortality after breast cancer was higher in childhood cancer survivors than in women with de novo breast cancer. This increased mortality reflects the burden of comorbidity and highlights the need for risk-reducing interventions.

A review of the influence of mammographic density on breast cancer clinical and pathological phenotype

PURPOSE

It is well established that high mammographic density (MD), when adjusted for age and body mass index, is one of the strongest known risk factors for breast cancer (BC), and also associates with higher incidence of interval cancers in screening due to the masking of early mammographic abnormalities. Increasing research is being undertaken to determine the underlying histological and biochemical determinants of MD and their consequences for BC pathogenesis, anticipating that improved mechanistic insights may lead to novel preventative or treatment interventions. At the same time, technological advances in digital and contrast mammography are such that the validity of well-established relationships needs to be re-examined in this context.

METHODS

With attention to old versus new technologies, we conducted a literature review to summarise the relationships between clinicopathologic features of BC and the density of the surrounding breast tissue on mammography, including the associations with BC biological features inclusive of subtype, and implications for the clinical disease course encompassing relapse, progression, treatment response and survival.

RESULTS AND CONCLUSIONS

There is reasonable evidence to support positive relationships between high MD (HMD) and tumour size, lymph node positivity and local relapse in the absence of radiotherapy, but not between HMD and LVI, regional relapse or distant metastasis. Conflicting data exist for associations of HMD with tumour location, grade, intrinsic subtype, receptor status, second primary incidence and survival, which need further confirmatory studies. We did not identify any relationships that did not hold up when data involving newer imaging techniques were employed in analysis.

Risk factors for metachronous contralateral breast cancer: A systematic review and meta-analysis

BACKGROUND

The risk of developing metachronous contralateral breast cancer (CBC) is a recurrent topic at the outpatient clinic. We aimed to provide CBC risk estimates of published patient, pathological, and primary breast cancer (PBC) treatment-related factors.

METHODS

PubMed was searched for publications on factors associated with CBC risk. Meta-analyses were performed with grouping of studies by mutation status (i.e., BRCA1, BRCA2, CHEK2 c.1100delC), familial cohorts, and general population-based cohorts.

RESULTS

Sixty-eight papers satisfied our inclusion criteria. Strong associations with CBC were found for carrying a BRCA1 (RR = 3.7; 95%CI:2.8-4.9), BRCA2 (RR = 2.8; 95%CI:1.8-4.3) or CHEK2 c.1100delC (RR = 2.7; 95%CI:2.0-3.7) mutation. In population-based cohorts, PBC family history (RR = 1.8; 95%CI:1.2-2.6), body mass index (BMI) ≥30 kg/m² (RR = 1.5; 95%CI:1.3-1.9), lobular PBC (RR = 1.4; 95%CI:1.1-1.8), estrogen receptor-negative PBC (RR = 1.5; 95%CI:1.0-2.3) and treatment with radiotherapy <40 years (RR = 1.4; 95%CI:1.1-1.7) was associated with increased CBC risk. Older age at PBC diagnosis (RR per decade = 0.93; 95%CI:0.88-0.98), and treatment with chemotherapy (RR = 0.7; 95%CI:0.6-0.8) or endocrine therapy (RR = 0.6; 95%CI:0.5-0.7) were associated with decreased CBC risk.

CONCLUSIONS

Mutation status, family history, and PBC treatment are key factors for CBC risk. Age at PBC diagnosis, BMI, lobular histology and hormone receptor status have weaker associations and should be considered in combination with key factors to accurately predict CBC risk.

"When I Needed It": Evaluation of the Use and Timing of Sharsheret's Thriving Again Program for Young Breast Cancer Survivors

Approximately 11% of all new breast cancer cases in the USA occur in women aged 45 years or younger. In 2011, CDC funded seven organizations to develop or enhance programs for young breast cancer survivors (YBCS). This paper analyzed program evaluation data collected by one of these organizations to gain a more nuanced understanding of how recipients used the newly developed program and resources for YBCS. Sharsheret's Thriving Again program was evaluated through a web-based survey of survivorship program participants. The evaluation asked questions about participant demographics, use of the kit's survivorship care plan (SCP), satisfaction with the timing of survivorship kit receipt, and factors related to survivors' use of additional Sharsheret programs. We conducted bivariate analyses of survey responses and calculated chi-square statistics for significance testing. Of the 163 women who responded to the survey, 43% were diagnosed with breast cancer at or before age 45 and 69% were of Jewish descent. The majority of women who used the SCP found it helpful to facilitate cancer treatment (94%), follow-up (85%), or discussions with providers (91%). A total of 75% of women who received the SCP kit while either recently diagnosed or undergoing treatment were satisfied with the timing of receipt. Survey respondents found the Thriving Again program and survivorship kit beneficial and indicated timing preferences for when to receive resources and support. Supporting the self-efficacy of cancer survivors may improve survivors' quality of life and is an important aspect of survivorship programs.

Comparison of Logistic Regression and Bayesian Networks for Risk Prediction of Breast Cancer Recurrence

Purpose. For individualized follow-up, accurate prediction of locoregional recurrence (LRR) and second primary (SP) breast cancer risk is required. Current prediction models employ regression, but with large data sets, machine-learning techniques such as Bayesian Networks (BNs) may be better alternatives. In this study, logistic regression was compared with different BNs, built with network classifiers and constraint- and score-based algorithms. Methods. Women diagnosed with early breast cancer between 2003 and 2006 were selected from the Netherlands Cancer Registry (NCR) ( N = 37,320). BN structures were developed using 1) Bayesian network classifiers, 2) correlation coefficients with different cutoffs, 3) constraint-based learning algorithms, and 4) score-based learning algorithms. The different models were compared with logistic regression using the area under the receiver operating characteristic curve, an external validation set obtained from the NCR from 2007 and 2008 ( N = 12,308), and subgroup analyses for a high- and low-risk group. Results. The BNs with the most links showed the best performance in both LRR and SP prediction (c-statistic of 0.76 for LRR and 0.69 for SP). In the external validation, logistic regression generally outperformed the BNs in both SP and LRR (c-statistic of 0.71 for LRR and 0.64 for SP). The differences were nonetheless small. Although logistic regression performed best on most parts of the subgroup analysis, BNs outperformed regression with respect to average risk for SP prediction in low- and high-risk groups. Conclusions. Although estimates of regression coefficients depend on other independent variables, there is no assumed dependence relationship between coefficient estimators and the change in value of other variables as in the case of BNs. Nonetheless, this analysis suggests that regression is still more accurate or at least as accurate as BNs for risk estimation for both LRRs and SP tumors.

Cumulative Risk Distribution for Interval Invasive Second Breast Cancers After Negative Surveillance Mammography

Purpose The aim of the current study was to characterize the risk of interval invasive second breast cancers within 5 years of primary breast cancer treatment. Methods We examined 65,084 surveillance mammograms from 18,366 women with a primary breast cancer diagnosis of unilateral ductal carcinoma in situ or stage I to III invasive breast carcinoma performed from 1996 to 2012 in the Breast Cancer Surveillance Consortium. Interval invasive breast cancer was defined as ipsilateral or contralateral cancer diagnosed within 1 year after a negative surveillance mammogram. Discrete-time survival models-adjusted for all covariates-were used to estimate the probability of interval invasive cancer, given the risk factors for each surveillance round, and aggregated across rounds to estimate the 5-year cumulative probability of interval invasive cancer. Results We observed 474 surveillance-detected cancers-334 invasive and 140 ductal carcinoma in situ-and 186 interval invasive cancers which yielded a cancer detection rate of 7.3 per 1,000 examinations (95% CI, 6.6 to 8.0) and an interval invasive cancer rate of 2.9 per 1,000 examinations (95% CI, 2.5 to 3.3). Median cumulative 5-year interval cancer risk was 1.4% (interquartile range, 0.8% to 2.3%; 10th to 90th percentile range, 0.5% to 3.7%), and 15% of women had ≥ 3% 5-year interval invasive cancer risk. Cumulative 5-year interval cancer risk was highest for women with estrogen receptor- and progesterone receptor-negative primary breast cancer (2.6%; 95% CI, 1.7% to 3.5%), interval cancer presentation at primary diagnosis (2.2%; 95% CI, 1.5% to 2.9%), and breast conservation without radiation (1.8%; 95% CI, 1.1% to 2.4%). Conclusion Risk of interval invasive second breast cancer varies across women and is influenced by characteristics that can be measured at initial diagnosis, treatment, and imaging. Risk prediction models that evaluate the risk of cancers not detected by surveillance mammography should be developed to inform discussions of tailored surveillance.

Incidence and Outcome of Breast Biopsy Procedures During Follow-up After Treatment for Breast Cancer

Importance

No comprehensive data are available regarding the frequency of breast biopsies performed during follow-up of treatment for invasive breast cancer.

Objective

To determine how often patients treated for breast cancer require breast biopsies during follow-up.

Design, Setting, and Participants

This nationwide population-based cohort study included 41 510 patients 64 years or younger in a commercial insurance database and 80 369 patients 66 years or older in the Surveillance, Epidemiology, and End Results (SEER)-Medicare database. Patients were diagnosed with incident invasive breast cancer (stages I-III) from January 1, 2000, through December 31, 2011. Diagnosis and procedural codes were used to identify biopsy rates during follow-up. Data were analyzed from March 3 through October 3, 2017.

Main Outcomes and Measures

Cumulative incidence and adjusted risk of breast biopsy and subsequent breast cancer treatment were calculated using the Kaplan-Meier method and Cox proportional hazards regression. All statistical tests were 2 sided.

Results

Among the 121 879 patients in the study population, 5- and 10-year overall incidences of breast biopsy were 14.7% and 23.4%, respectively, in the commercial insurance cohort and 11.8% and 14.9%, respectively, in the SEER-Medicare cohort. The 5-year estimated incidence of breast biopsy was higher among women treated with brachytherapy (24.0% in the commercial insurance and 25.0% in the SEER-Medicare cohorts) than among those treated with whole-breast irradiation (16.7% in the commercial insurance and 15.1% in the SEER-Medicare cohorts) and persisted after multivariate adjustment in the commercial insurance (hazard ratio [HR], 1.53; 95% CI, 1.38-1.70; P < .001) and SEER-Medicare (HR, 1.76; 95% CI, 1.63-1.91; P < .001) cohorts. Adjuvant chemotherapy use (HR, 1.31; 95% CI, 1.25-1.37; P < .001) and patient age (>85 vs 66-69 years; HR, 0.40; 95% CI, 0.36-0.44; P < .001) in the SEER-Medicare cohort and endocrine therapy in the commercial insurance (HR, 0.88; 95% CI, 0.82-0.93; P < .001) and SEER-Medicare (HR, 0.91; 95% CI, 0.85-0.97; P = .002) cohorts were independently associated with biopsy. After unilateral mastectomy, the estimated 5-year contralateral breast biopsy rates were 10.4% and 7.7% in the commercial insurance and SEER-Medicare cohorts, respectively. Of the patients with breast biopsy, 1239 of 4158 patients (29.8%) in the commercial insurance cohort and 2258 of 9747 patients (23.2%) in the SEER-Medicare cohort underwent subsequent cancer treatment.

Conclusions and Relevance

These data on the need for breast biopsies during follow-up and subsequent treatments from a large cohort of women with commercial insurance and Medicare can be used in the context of therapy-planning discussions and survivorship expectations for patients with breast cancer.

Breast Biopsy Intensity and Findings Following Breast Cancer Screening in Women With and Without a Personal History of Breast Cancer

IMPORTANCE

There is little evidence on population-based harms and benefits of screening breast magnetic resonance imaging (MRI) in women with and without a personal history of breast cancer (PHBC).

OBJECTIVE

To evaluate biopsy rates and yield in the 90 days following screening (mammography vs magnetic resonance imaging with or without mammography) among women with and without a PHBC.

DESIGN, SETTING, AND PARTICIPANTS

Observational cohort study of 6 Breast Cancer Surveillance Consortium (BCSC) registries. Population-based sample of 812 164 women undergoing screening, 2003 through 2013.

EXPOSURES

A total of 2 048 994 digital mammography and/or breast MRI screening episodes (mammogram alone vs MRI with or without screening mammogram within 30 days).

MAIN OUTCOMES AND MEASURES

Biopsy intensity (surgical greater than core greater than fine-needle aspiration) and yield (invasive cancer greater than ductal carcinoma in situ greater than high-risk benign greater than benign) within 90 days of a screening episode. We computed age-adjusted rates of biopsy intensity (per 1000 screening episodes) and biopsy yield (per 1000 screening episodes with biopsies). Outcomes were stratified by PHBC and by BCSC 5-year breast cancer risk among women without PHBC.

RESULTS

We included 101 103 and 1 939 455 mammogram screening episodes in women with and without PHBC, respectively; MRI screening episodes included 3763 with PHBC and 4673 without PHBC. Age-adjusted core and surgical biopsy rates (per 1000 episodes) doubled (57.1; 95% CI, 50.3-65.1) following MRI compared with mammography (23.6; 95% CI, 22.4-24.8) in women with PHBC. Differences (per 1000 episodes) were even larger in women without PHBC: 84.7 (95% CI, 75.9-94.9) following MRI and 14.9 (95% CI, 14.7-15.0) following mammography episodes. Ductal carcinoma in situ and invasive biopsy yield (per 1000 episodes) was significantly higher following mammography compared with MRI episodes in women with PHBC (mammography, 404.6; 95% CI, 381.2-428.8; MRI, 267.6; 95% CI, 208.0-337.8) and nonsignificantly higher, but in the same direction, in women without PHBC (mammography, 279.3; 95% CI, 274.2-284.4; MRI, 214.6; 95% CI, 158.7-280.8). High-risk benign lesions were more commonly identified following MRI regardless of PHBC. Higher biopsy rates and lower cancer yield following MRI were not explained by increasing age or higher 5-year breast cancer risk.

CONCLUSIONS AND RELEVANCE

Women with and without PHBC who undergo screening MRI experience higher biopsy rates coupled with significantly lower cancer yield findings following biopsy compared with screening mammography alone. Further work is needed to identify women who will benefit from screening MRI to ensure an acceptable benefit-to-harm ratio.

The association of mammographic density with risk of contralateral breast cancer and change in density with treatment in the WECARE study

Background

Mammographic density (MD) is an established predictor of risk of a first breast cancer, but the relationship of MD to contralateral breast cancer (CBC) risk is not clear, including the roles of age, mammogram timing, and change with treatment. Multivariable prediction models for CBC risk are needed and MD could contribute to these.

Methods

We conducted a case-control study of MD and CBC risk in phase II of the WECARE study where cases had a CBC diagnosed ≥ 2 years after first diagnosis at age <55 years and controls had unilateral breast cancer (UBC) with similar follow-up time. We retrieved film mammograms of the unaffected breast from two time points, prior to/at the time of the first diagnosis (253 CBC cases, 269 UBC controls) and ≥ 6 months up to 48 months following the first diagnosis (333 CBC cases, 377 UBC controls). Mammograms were digitized and percent MD (%MD) was measured using the thresholding program Cumulus. Odds ratios (OR) and 95% confidence intervals (CI) for association between %MD and CBC, adjusted for age, treatment, and other factors related to CBC, were estimated using logistic regression. Linear regression was used to estimate the association between treatment modality and change in %MD in 467 women with mammograms at both time points.

Results

For %MD assessed following diagnosis, there was a statistically significant trend of increasing CBC with increasing %MD (p = 0.03). Lower density (<25%) was associated with reduced risk of CBC compared to 25 to < 50% density (OR 0.69, 95% CI 0.49, 0.98). Similar, but weaker, associations were noted for %MD measurements prior to/at diagnosis. The relationship appeared strongest in women aged < 45 years and non-existent in women aged 50 to 54 years. A decrease of ≥ 10% in %MD between first and second mammogram was associated marginally with reduced risk of CBC (OR 0.63, 95% CI 0.40, 1.01) compared to change of <10%. Both tamoxifen and chemotherapy were associated with statistically significant 3% decreases in %MD (p < 0.01).

Conclusions

Post-diagnosis measures of %MD may be useful to include in CBC risk prediction models with consideration of age at diagnosis. Chemotherapy is associated with reductions in %MD, similar to tamoxifen.

Electronic supplementary material

The online version of this article (10.1186/s13058-018-0948-4) contains supplementary material, which is available to authorized users.

Use of Breast Imaging After Treatment for Locoregional Breast Cancer (AFT-01)

BACKGROUND

Annual mammography is recommended after breast cancer treatment. However, studies suggest its under-utilization for Medicare patients. Utilization in the broader population is unknown, as is the role of breast magnetic resonance imaging (MRI). Understanding factors associated with imaging use is critical to improvement of adherence to recommendations.

METHODS

A random sample of 9835 eligible patients receiving surgery for stages 2 and 3 breast cancer from 2006 to 2007 was selected from the National Cancer Database for primary data collection. Imaging and recurrence data were abstracted from patients 90 days after surgery to 5 years after diagnosis. Factors associated with lack of imaging were assessed using multivariable repeated measures logistic regression with generalized estimating equations. Patients were censored for death, bilateral mastectomy, new cancer, and recurrence.

RESULTS

Of 9835 patients, 9622, 8702, 8021, and 7457 patients were eligible for imaging at surveillance years 1 through 4 respectively. Annual receipt of breast imaging declined from year 1 (69.5%) to year 4 (61.0%), and breast MRI rates decreased from 12.5 to 5.8%. Lack of imaging was associated with age 80 years or older and age younger than 50 years, black race, public or no insurance versus private insurance, greater comorbidity, larger node-positive hormone receptor-negative tumor, excision alone or mastectomy, and no chemotherapy (p < 0.005). Receipt of breast MRI was associated with age younger than 50 years, white race, higher education, private insurance, mastectomy, chemotherapy, care at a teaching/research facility, and MRI 12 months before diagnosis (p < 0.05).

CONCLUSION

Under-utilization of mammography after breast cancer treatment is associated with sociodemographic and clinical factors, not institutional characteristics. Effective interventions are needed to increase surveillance mammography for at-risk populations. ClinicalTrials.gov Identifier: NCT02171078.

Stromal characteristics may hold the key to mammographic density: the evidence to date

There is strong epidemiological data indicating a role for increased mammographic density (MD) in predisposing to breast cancer, however, the biological mechanisms underlying this phenomenon are less well understood. Recently, studies of human breast tissues have started to characterise the features of mammographically dense breasts, and a number of in-vitro and in-vivo studies have explored the potential mechanisms through which dense breast tissue may exert this tumourigenic risk. This article aims to review both the pathological and biological evidence implicating a key role for the breast stromal compartment in MD, how this may be modified and the clinical significance of these findings. The epidemiological context will be briefly discussed but will not be covered in detail.

Interactions of Family History of Breast Cancer with Radiotherapy in Relation to the Risk of Breast Cancer Recurrence

Purpose

We examined associations between a family history of breast cancer and the risk of breast cancer recurrence in women who received or did not receive radiotherapy.

Methods

Our study included 2,440 women enrolled in the Breast Cancer Registry of Greater Cincinnati. Information on breast cancer risk factors, including detailed family history of breast cancer, characteristics of the primary tumor, treatment received, and recurrence status was collected at baseline and via updates. Associations between a family history of breast cancer and the risk of breast cancer recurrence were examined separately in women treated with and without radiotherapy using survival analysis.

Results

Over an average follow-up time of 8.78 years, we found no associations between a family history of breast cancer and the risk of breast cancer recurrence among women with a history of radiotherapy (hazard ratio [HR], 0.96; 95% confidence interval [CI], 0.75–1.23). Among women who did not receive radiotherapy, the total number of relatives with breast cancer was positively associated with the risk of breast cancer recurrence (HR, 1.21; 95% CI, 1.00–1.47). We found no interactions of radiotherapy with family history (p-interaction >0.05).

Conclusion

Radiotherapy for a primary breast cancer in women with a family history of breast cancer does not increase risk of breast cancer recurrence. If these findings are replicated in future studies, the results may translate into an important health message for breast cancer survivors with a family history of breast cancer.

Surveillance Mammography in Older Patients With Breast Cancer-Can We Ever Stop?: A Review

IMPORTANCE

Approximately 4% to 5% of breast cancer survivors will develop a new ipsilateral or contralateral cancer (in-breast event) over the 5 years following diagnosis, and annual surveillance mammography is recommended for those with residual breast tissue. The risk for such in-breast events persists over time, though increasing age at cancer diagnosis and treatment with hormonal therapy are associated with lower risk, and most older survivors of breast cancer will ultimately die from nonbreast cancer-related causes. Specific guidelines for surveillance strategies in older patients are limited. Prospective data on the benefits and harms of surveillance mammography in this population are lacking, and most of the evidence is derived from observational, retrospective data, often in the general population.

OBSERVATIONS

We review the current recommendations for breast cancer screening and surveillance for older patients, the current evidence for ipsilateral and contralateral breast cancer risks in older survivors of breast cancer, and suggested approaches for discussions about surveillance mammography with older patients. We recommend individualized decision making for surveillance breast imaging in older survivors of breast cancer, with consideration of the following strategy for women 70 years or older: 1-time imaging 6 to 12 months after completion of local therapy followed by annual or biennial surveillance mammography for healthy women and cessation of mammography in patients whose life expectancy is less than 5 years to 10 years, regardless of age. Decisions on mammographic surveillance should also incorporate whether hormonal therapy is being administered, whether a patient's anticipated life expectancy is extraordinary, and whether a patient's individual risk for in-breast events is higher (or lower) than average risk for breast cancer survivors.

CONCLUSIONS AND RELEVANCE

We propose reframing discussions around surveillance mammography in older breast cancer survivors and to consider cessation while taking into account life expectancy, the estimated risk for subsequent in-breast events, and patient preferences.

Mammographic Breast Density and Breast Cancer Risk: Implications of the Breast Density Legislation for Health Care Practitioners

Breast density has emerged as a critical phenotypic marker of increased breast cancer risk. The breast density legislation, passed in multiple states, requires patient notification of the implications of the breast density on breast cancer risk and screening. Supplemental screening may be suggested in the state regulation; however, there are limited data to guide conversations with patients. This article will review the current state of supplemental screening in women with dense breasts and discuss theories of the mechanism of action. Guidance is provided to assist in shared decision making and appropriate patient counseling.

Breast ultrasonography for detection of metachronous ipsilateral breast tumor recurrence

BACKGROUND

Early detection of recurrence improves the survival rate of patients treated with breast conservation therapy (BCT). Therefore, ultrasonography (US) may be useful for metachronous ipsilateral breast tumor recurrence (MIBTR) obscured on mammography by dense breast tissue and distortion.

PURPOSE

To evaluate clinical, radiologic, and pathologic findings of MIBTR retrospectively, and to assess the role of surveillance US additional to mammography for MIBTR detection.

MATERIAL AND METHODS

During 2000 to 2012, 28 MIBTR were collected and reviewed among 2958 women treated for primary breast cancer with conservation surgery. The detection rates of imaging studies for identifying metachronous ipsilateral lesions were assessed and compared. MIBTR tumor staging was evaluated according to imaging modality for detection of MIBTR, palpability, and recent imaging surveillance.

RESULTS

No significant difference was observed in the detection rate between mammography and US for overall MIBTR (84.2% vs. 85.7%; P = 0.898) or non-palpable MIBTR (88.2% vs. 81.0%; P = 0.566). US alone identified 33.3% of non-palpable MIBTRs (seven of 21). Among these cases, two had negative mammograms. All 14 MIBTRs with recent imaging surveillance were stage T2 or less, and all seven MIBTRs detected by US alone were in situ or T1; 33% of MIBTRs without recent imaging surveillance were T3 or T4.

CONCLUSION

The overall MIBTR detection rate by US was not higher than the detection rate of mammography, although combined surveillance with US and mammography found MIBTRs slightly earlier than mammography alone.

Five-year risk of interval-invasive second breast cancer

BACKGROUND

Earlier detection of second breast cancers after primary breast cancer (PBC) treatment improves survival, yet mammography is less accurate in women with prior breast cancer. The purpose of this study was to examine women presenting clinically with second breast cancers after negative surveillance mammography (interval cancers), and to estimate the five-year risk of interval-invasive second cancers for women with varying risk profiles.

METHODS

We evaluated a prospective cohort of 15 114 women with 47 717 surveillance mammograms diagnosed with stage 0-II unilateral PBC from 1996 through 2008 at facilities in the Breast Cancer Surveillance Consortium. We used discrete time survival models to estimate the association between odds of an interval-invasive second breast cancer and candidate predictors, including demographic, PBC, and imaging characteristics. All statistical tests were two-sided.

RESULTS

The cumulative incidence of second breast cancers after five years was 54.4 per 1000 women, with 325 surveillance-detected and 138 interval-invasive second breast cancers. The five-year risk of interval-invasive second cancer for women with referent category characteristics was 0.60%. For women with the most and least favorable profiles, the five-year risk ranged from 0.07% to 6.11%. Multivariable modeling identified grade II PBC (odds ratio [OR] = 1.95, 95% confidence interval [CI] = 1.15 to 3.31), treatment with lumpectomy without radiation (OR = 3.27, 95% CI = 1.91 to 5.62), interval PBC presentation (OR = 2.01, 95% CI 1.28 to 3.16), and heterogeneously dense breasts on mammography (OR = 1.54, 95% CI = 1.01 to 2.36) as independent predictors of interval-invasive second breast cancers.

CONCLUSIONS

PBC diagnosis and treatment characteristics contribute to variation in subsequent-interval second breast cancer risk. Consideration of these factors may be useful in developing tailored post-treatment imaging surveillance plans.

Variation in Breast Cancer-Risk Factor Associations by Method of Detection: Results From a Series of Case-Control Studies

Concerns about breast cancer overdiagnosis have increased the need to understand how cancers detected through screening mammography differ from those first detected by a woman or her clinician. We investigated risk factor associations for invasive breast cancer by method of detection within a series of case-control studies (1992-2007) carried out in Wisconsin, Massachusetts, and New Hampshire (n=15,648 invasive breast cancer patients and 17,602 controls aged 40-79 years). Approximately half of case women reported that their cancer had been detected by mammographic screening and half that they or their clinician had detected it. In polytomous logistic regression models, parity and age at first birth were more strongly associated with risk of mammography-detected breast cancer than with risk of woman/clinician-detected breast cancer (P≤0.01; adjusted for mammography utilization). Among postmenopausal women, estrogen-progestin hormone use was predominantly associated with risk of woman/clinician-detected breast cancer (odds ratio (OR)=1.49, 95% confidence interval (CI): 1.29, 1.72), whereas obesity was predominantly associated with risk of mammography-detected breast cancer (OR=1.72, 95% CI: 1.54, 1.92). Among regularly screened premenopausal women, obesity was not associated with increased risk of mammography-detected breast cancer (OR=0.99, 95% CI: 0.83, 1.18), but it was associated with reduced risk of woman/clinician-detected breast cancer (OR=0.53, 95% CI: 0.43, 0.64). These findings indicate important differences in breast cancer risk factors according to method of detection.

Metabolic syndrome and outcomes following early-stage breast cancer

The prevalence of risk factors contributing to metabolic syndrome (MetS) is increasing, and numerous components of MetS are associated with increased primary breast cancer (BC) risk. However, less is known about the relationship of MetS to BC outcomes. The aim of this study was to evaluate whether MetS, characterized by increased weight, hypertension, low HDL-cholesterol, high triglycerides, and diabetes or impaired glucose tolerance, is associated with risk of second breast cancer events (SBCE) and BC-specific mortality. Retrospective cohort study of women diagnosed with incident early-stage (I-II) BC between 1990 and 2008, enrolled in an integrated health plan. Outcomes of interest were SBCE, defined as recurrence or second primary BC, and BC-specific mortality. We used multivariable Cox proportional hazards models to estimate adjusted hazard ratios (HR) and 95% confidence intervals (CI) for time-varying exposure to MetS components while accounting for potential confounders and competing risks. Among 4,216 women in the cohort, 26% had ≥3 MetS components and 13% developed SBCE during median follow-up of 6.3 years. Compared to women with no MetS components, presence of MetS (≥3 components) was associated with increased risk of SBCE (HR = 1.50, 95% CI 1.08-2.07) and BC-specific mortality (HR = 1.65, 95% CI 1.02-2.69). Of the individual components, only increased weight was associated with increased risk of SBCE (HR = 1.26, 95% CI 1.06-1.49). MetS is associated with modestly increased risk of SBCE and BC-specific mortality. Given the growing population of BC survivors, further research in larger and more diverse populations is warranted.

A joint model for multistate disease processes and random informative observation times, with applications to electronic medical records data

Multistate models are used to characterize individuals' natural histories through diseases with discrete states. Observational data resources based on electronic medical records pose new opportunities for studying such diseases. However, these data consist of observations of the process at discrete sampling times, which may either be pre-scheduled and non-informative, or symptom-driven and informative about an individual's underlying disease status. We have developed a novel joint observation and disease transition model for this setting. The disease process is modeled according to a latent continuous-time Markov chain; and the observation process, according to a Markov-modulated Poisson process with observation rates that depend on the individual's underlying disease status. The disease process is observed at a combination of informative and non-informative sampling times, with possible misclassification error. We demonstrate that the model is computationally tractable and devise an expectation-maximization algorithm for parameter estimation. Using simulated data, we show how estimates from our joint observation and disease transition model lead to less biased and more precise estimates of the disease rate parameters. We apply the model to a study of secondary breast cancer events, utilizing mammography and biopsy records from a sample of women with a history of primary breast cancer.

A patient-level calibration framework for evaluating surveillance strategies: a case study of mammographic follow-up after early breast cancer

OBJECTIVE

Currently all women who have completed their primary treatment for early breast cancer are invited to receive routine annual mammography. There is no randomized controlled trial evidence to support this schedule, and model-based analysis is required. This paper describes a novel data collection and model calibration process to analyze the cost-effectiveness of alternative follow-up schedules for early breast cancer survivors.

METHODS

A discrete event simulation model describes the progression of early breast cancer after the completion of primary treatment, representing impalpable and palpable recurrence and the detection of impalpable disease via follow-up mammography. Retrospective data from the South Australian Cancer Registry and clinical and administrative hospital databases were linked for 407 postmenopausal women diagnosed with moderate-prognosis early breast cancer from 2000 to 2008. These data formed the basis of a patient-level probabilistic calibration process.

RESULTS

For 50- to 69-year-old survivors, annual follow-up for 5 years, with visits every 2 years thereafter, appears to be cost-effective. For women aged 70 to 79 years at diagnosis, a surveillance schedule similar to general population screening (2 yearly) appears to be most cost-effective if high rates of adherence can be maintained.

CONCLUSIONS

This study demonstrated the potential value of combining linked, retrospective data and decision analytic modeling to provide estimates of costs and health outcomes that are sufficiently robust to inform cancer clinical guidelines and individual patient decisions regarding appropriate follow-up schedules.

Contralateral prophylactic mastectomy in the American College of Radiology Imaging Network 6667 trial: effect of breast MR imaging assessments and patient characteristics

PURPOSE

To assess which patient and magnetic resonance (MR) imaging factors are associated with the likelihood of contralateral prophylactic mastectomy (CPM) in patients with newly diagnosed breast cancer.

MATERIALS AND METHODS

The American College of Radiology Imaging Network 6667 trial was compliant with HIPAA; institutional review board approval was obtained at each site. All patients provided written informed consent. This study was a retrospective review of data from 934 women enrolled in the trial who did not have a known contralateral breast cancer at the time of surgical planning. The authors assessed age, menopausal status, index breast cancer histologic results, contralateral breast histologic results, breast density, family history, race and/or ethnicity, MR imaging Breast Imaging Reporting and Data System (BI-RADS) assessment, and number of MR imaging lesions for association with CPM by using the Fisher exact test, exact χ(2) test, and multivariate logistic regression analyses.

RESULTS

Eighty-six of the 934 (9.2%) women underwent CPM and were more likely to be younger (mean age, 48 years [range, 27-78 years] vs mean age, 54 years [range, 25-86 years]; P < .0001), be premenopausal (55 of 86 [64%] vs 349 of 845 [41%], P < .0001), have ductal carcinoma in situ (DCIS) in the index breast (31% [27 of 86] vs 19% [164 of 848], P = .02), have greater breast density (71 of 86 [83%] vs 572 of 848 [68%], P = .004), and have a family history of breast cancer (44 of 86 [30%] vs 150 of 488 [18%], P = .01) than those who did not undergo CPM. Distributions of race and/or ethnicity, contralateral lesion pathologic results, and number of MR imaging lesions were similar in both groups. With multivariate modeling, younger age, greater breast density, DCIS index cancer, and family history remained significant, whereas menopausal status did not. Positive MR imaging assessments were not significantly more frequent in the CPM group than in the group of women who did not undergo CPM (14 of 86 [16.3%] vs 113 of 848 [13.3%], P = .43).

CONCLUSION

In patients with newly diagnosed breast cancer who underwent breast MR imaging at which a contralateral breast cancer was not identified, patient factors and not breast MR imaging BI-RADS scores were chief determinants in decisions regarding CPM. Online supplemental material is available for this article.

Mammographic density-a review on the current understanding of its association with breast cancer

There has been considerable recent interest in the genetic, biological and epidemiological basis of mammographic density (MD), and the search for causative links between MD and breast cancer (BC) risk. This report will critically review the current literature on MD and summarize the current evidence for its association with BC. Keywords 'mammographic dens*', 'dense mammary tissue' or 'percent dens*' were used to search the existing literature in English on PubMed and Medline. All reports were critically analyzed. The data were assigned to one of the following aspects of MD: general association with BC, its relationship with the breast hormonal milieu, the cellular basis of MD, the generic variations of MD, and its significance in the clinical setting. MD adjusted for age, and BMI is associated with increased risk of BC diagnosis, advanced tumour stage at diagnosis and increased risk of both local recurrence and second primary cancers. The MD measures that predict BC risk have high heritability, and to date several genetic markers associated with BC risk have been found to also be associated with these MD risk predictors. Change in MD could be a predictor of the extent of chemoprevention with tamoxifen. Although the biological and genetic pathways that determine and perhaps modulate MD remain largely unresolved, significant inroads are being made into the understanding of MD, which may lead to benefits in clinical screening, assessment and treatment strategies. This review provides a timely update on the current understanding of MD's association with BC risk.

Factors associated with long-term adherence to annual surveillance mammography among breast cancer survivors

Clinical practice guidelines recommend yearly surveillance mammography for breast cancer survivors, yet many women do not receive this service. The objective of this study was to evaluate factors related to long-term surveillance mammography adherence among breast cancer survivors. We conducted a retrospective cohort study among women ≥ 18 years, diagnosed with incident stage I or II breast cancer between 1990 and 2008. We used medical record and administrative health plan data to ascertain covariates and receipt of surveillance mammography for up to 10 years after completing breast cancer treatment. Surveillance included post-diagnosis screening exams among asymptomatic women. We used multivariable repeated measures generalized estimating equation regression models to estimate odds ratios and robust 95 % confidence intervals to examine factors related to the annual receipt of surveillance mammography. The analysis included 3,965 women followed for a median of six surveillance years; 79 % received surveillance mammograms in year 1 but decreased to 63 % in year 10. In multivariable analyses, women, who were < 40 years or 80+ years of age (compared to 50-59 years), current smokers, had greater comorbidity, were diagnosed more recently, had stage II cancer, or were treated with mastectomy or breast conserving surgery without radiation, were less likely than other women to receive surveillance mammography. Women with outpatient visits during the year to primary care providers, oncologists, or both were more likely to undergo surveillance. In this large cohort study of women diagnosed with early-stage invasive breast cancer, we found that important subgroups of women are at high risk for non-adherence to surveillance recommendations, even among younger breast cancer survivors. Efforts should be undertaken to actively engage breast cancer survivors in managing long-term surveillance care.

Time to definitive diagnosis of breast cancer in Latina and non-Hispanic white women: the six cities study

Time delay after an abnormal screening mammogram may have a critical impact on tumor size, stage at diagnosis, treatment, prognosis, and survival of subsequent breast cancer. This study was undertaken to evaluate disparities between Latina and non-Hispanic white (NHW) women in time to definitive diagnosis of breast cancer after an abnormal screening mammogram, as well as factors contributing to such disparities. As part of the activities of the National Cancer Institute (NCI)-funded Redes En Acción research network, clinical records of 186 Latinas and 74 NHWs who received abnormal screening mammogram results were reviewed to determine the time to obtain a definitive diagnosis. Data was obtained from participating clinics in six U.S. cities and included demographics, clinical history, and mammogram characteristics. Kaplan-Meier estimates and Cox proportional hazards models were used to test differences in median time to definitive diagnosis by ethnicity after adjusting for clinic site, demographics, and clinical characteristics. Time-to-event analysis showed that Latinas took 2.2 times longer to reach 50% definitively diagnosed with breast cancer relative to NHWs, and three times longer to reach 80% diagnosed (p=0.001). Latinas' median time to definitive diagnosis was 60 days compared to 27 for NHWs, a 59% gap in diagnosis rates (adjusted Hazard Ratio [aHR] = 1.59, 95% CI = 1.09, 2.31; p=0.015). BI-RADS-4/5 women's diagnosis rate was more than twice that of BI-RADS-3 (aHR = 2.11, 95% CI = 1.18, 3.78; p=0.011). Disparities in time between receipt of abnormal screening result and definitive diagnosis adversely affect Latinas compared to NHWs, and remain significant after adjusting for demographic and clinical variables. With cancer now the leading cause of mortality among Latinos, a greater need exists for ethnically and culturally appropriate interventions like patient navigation to facilitate Latinas' successful entry into, and progression through, the cancer care system.

Long-term surveillance mammography and mortality in older women with a history of early stage invasive breast cancer

Annual surveillance mammograms in older long-term breast cancer survivors are recommended, but this recommendation is based on little evidence and with no guidelines on when to stop. Surveillance mammograms should decrease breast cancer mortality by detecting second breast cancer events at an earlier stage. We examined the association between surveillance mammography beyond 5 years after diagnosis on breast cancer-specific mortality in a cohort of women aged ≥ 65 years diagnosed 1990-1994 with early stage breast cancer. Our cohort included women who survived disease free for ≥ 5 years (N = 1,235) and were followed from year 6 through death, disenrollment, or 15 years after diagnosis. Asymptomatic surveillance mammograms were ascertained through medical record review. We used Cox proportional hazards regression stratified by follow-up year to calculate the association between time-varying surveillance mammography and breast cancer-specific and other-than-breast mortality adjusting for site, stage, primary surgery type, age and time-varying Charlson Comorbidity Index. The majority (85 %) of the 1,235 5-year breast cancer survivors received ≥ 1 surveillance mammogram in years 5-9 (yearly proportions ranged from 48 to 58 %); 82 % of women received ≥ 1 surveillance mammogram in years 10-14. A total of 120 women died of breast cancer and 393 women died from other causes (average follow-up 7.3 years). Multivariable models and lasagna plots suggested a modest reduction in breast cancer-specific mortality with surveillance mammogram receipt in the preceding year (IRR 0.82, 95 % CI 0.56-1.19, p = 0.29); the association with other-cause mortality was 0.95 (95 % CI 0.78-1.17, p = 0.64). Among older breast cancer survivors, surveillance mammography may reduce breast cancer-specific mortality even after 5 years of disease-free survival. Continuing surveillance mammography in older breast cancer survivors likely requires physician-patient discussions similar to those recommended for screening, taking into account comorbid conditions and life-expectancy.

Opportunities for public health communication, intervention, and future research on breast cancer in younger women

BACKGROUND

Approximately 6% of breast cancers in the United States occur in women under the age of 40 years. Compared with women ≥40 years of age, younger women are diagnosed at later stages, have higher rates of recurrence and death, and may be predisposed to secondary breast or ovarian cancer. An informal meeting of experts discussed opportunities for research and public health communication related to breast cancer among young (<40 and/or premenopausal) women.

METHODS

In September 2011, the Centers for Disease Control and Prevention hosted 18 experts in oncology, genetics, behavioral science, survivorship and advocacy, public health, communication, ethics, nutrition, physical activity, and environmental health. They (1) reviewed research and programmatic knowledge on risk and preventive factors, early detection, and survivorship; and (2) discussed ideas for research, communication, and programmatic efforts related to young women diagnosed with or at risk for early onset breast cancer.

RESULTS

Levels of evidence and themes for future research regarding risk and preventive factors, including exposures, were discussed. Early detection strategies, including screening, risk assessment, and genetic counseling, as well as survivorship issues, follow-up care, fertility and reproductive health, and psychosocial care were highlighted.

CONCLUSION

Community and academic researchers, providers, advocates, and the federal public health community discussed strategies and opportunities for this unique population. Although the evidence is limited, future research and communication activities may be useful to organize future public health initiatives.

Risk factors for second screen-detected or interval breast cancers in women with a personal history of breast cancer participating in mammography screening

BACKGROUND

Women with a personal history of breast cancer (PHBC) have increased risk of an interval cancer. We aimed to identify risk factors for second (ipsilateral or contralateral) screen-detected or interval breast cancer within 1 year of screening in PHBC women.

METHODS

Screening mammograms from women with history of early-stage breast cancer at Breast Cancer Surveillance Consortium-affiliated facilities (1996-2008) were examined. Associations between woman-level, screen-level, and first cancer variables and the probability of a second breast cancer were modeled using multinomial logistic regression for three outcomes [screen-detected invasive breast cancer, interval invasive breast cancer, or ductal carcinoma in situ (DCIS)] relative to no second breast cancer.

RESULTS

There were 697 second breast cancers, of these 240 were interval cancers, among 67,819 screens in 20,941 women. In separate models for women with DCIS or invasive first cancer, first breast cancer surgery predicted all three second breast cancer outcomes (P < 0.001), and high ORs for second breast cancers (between 1.95 and 4.82) were estimated for breast conservation without radiation (relative to mastectomy). In women with invasive first breast cancer, additional variables predicted risk (P < 0.05) for at least one of the three outcomes: first-degree family history, dense breasts, longer time between mammograms, young age at first breast cancer, first breast cancer stage, and adjuvant systemic therapy for first breast cancer; and risk of interval invasive breast cancer was highest in women <40 years at first breast cancer (OR, 3.41; 1.34-8.70), those with extremely dense breasts (OR, 2.55; 1.4-4.67), and those treated with breast conservation without radiation (OR, 2.67; 1.53-4.65).

CONCLUSION

Although the risk of a second breast cancer is modest, our models identify risk factors for interval second breast cancer in PHBC women.

IMPACT

Our findings may guide discussion and evaluations of tailored breast screening in PHBC women, and incorporating this information into clinical decision-making warrants further research.