Methodology for Using Real-World Data From Electronic Health Records to Assess Chemotherapy Administration in Women With Breast Cancer

PURPOSE

Identification of patients' intended chemotherapy regimens is critical to most research questions conducted in the real-world setting of cancer care. Yet, these data are not routinely available in electronic health records (EHRs) at the specificity required to address these questions. We developed a methodology to identify patients' intended regimens from EHR data in the Optimal Breast Cancer Chemotherapy Dosing (OBCD) study.

METHODS

In women older than 18 years, diagnosed with primary stage I-IIIA breast cancer at Kaiser Permanente Northern California (2006-2019), we categorized participants into 24 drug combinations described in National Comprehensive Cancer Network guidelines for breast cancer treatment. Participants were categorized into 50 guideline chemotherapy administration schedules within these combinations using an iterative algorithm process, followed by chart abstraction where necessary. We also identified patients intended to receive nonguideline administration schedules within guideline drug combinations and nonguideline drug combinations. This process was adapted at Kaiser Permanente Washington using abstracted data (2004-2015).

RESULTS

In the OBCD cohort, 13,231 women received adjuvant or neoadjuvant chemotherapy, of whom 10,213 (77%) had their intended regimen identified via the algorithm, 2,416 (18%) had their intended regimen identified via abstraction, and 602 (4.5%) could not be identified. Across guideline drug combinations, 111 nonguideline dosing schedules were used, alongside 61 nonguideline drug combinations. A number of factors were associated with requiring abstraction for regimen determination, including: decreasing neighborhood household income, earlier diagnosis year, later stage, nodal status, and human epidermal growth factor receptor 2 (HER2)+ status.

CONCLUSION

We describe the challenges and approaches to operationalize complex, real-world data to identify intended chemotherapy regimens in large, observational studies. This methodology can improve efficiency of use of large-scale clinical data in real-world populations, helping answer critical questions to improve care delivery and patient outcomes.

Modifying Effects of Genetic Variations on the Association Between Dietary Isothiocyanate Exposure and Non-muscle Invasive Bladder Cancer Prognosis in the Be-Well Study

SCOPE

Dietary isothiocyanate (ITC) exposure from cruciferous vegetable (CV) intake may improve non-muscle invasive bladder cancer (NMIBC) prognosis. This study aims to investigate whether genetic variations in key ITC-metabolizing/functioning genes modify the associations between dietary ITC exposure and NMIBC prognosis outcomes.

METHODS AND RESULTS

In the Bladder Cancer Epidemiology, Wellness, and Lifestyle Study (Be-Well Study), a prospective cohort of 1472 incident NMIBC patients, dietary ITC exposure is assessed by self-reported CV intake and measured in plasma ITC-albumin adducts. Using Cox proportional hazards regression models, stratified by single nucleotide polymorphisms (SNPs) in nine key ITC-metabolizing/functioning genes, it is calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for recurrence and progression. The rs15561 in N-acetyltransferase 1 (NAT1) is alter the association between CV intake and progression risk. Multiple SNPs in nuclear factor E2-related factor 2 (NRF2) and nuclear factor kappa B (NFκB) are modify the associations between plasma ITC-albumin adduct level and progression risk (pint < 0.05). No significant association is observed with recurrence risk. Overall, >80% study participants are present with at least one protective genotype per gene, showing an average 65% reduction in progression risk with high dietary ITC exposure.

CONCLUSION

Despite that genetic variations in ITC-metabolizing/functioning genes may modify the effect of dietary ITCs on NMIBC prognosis, dietary recommendation of CV consumption may help improve NMIBC survivorship.

Clinical, Epidemiologic, and Pathologic Significance of ERBB2-Low Expression in Breast Cancer

Importance

It is unclear whether breast cancer (BC) with low ERBB2 expression (ERBB2-low) is a distinct clinical, pathological, and epidemiological entity from BC classified as no ERBB2 expression (ERBB2-negative).

Objective

To evaluate the clinical, pathological, and epidemiologic features of BC with ERBB2-low expression compared with ERBB2-negative BC in a large population study.

Design, Setting, and Participants

This cohort study was conducted as part of the Pathways Study, a prospective, racially and ethnically diverse cohort study of women with BC enrolled between 2006 and 2013 in Kaiser Permanente Northern California (KPNC). The hematoxylin and eosin slides underwent centralized pathology review, including the percentage of tumor infiltrating lymphocytes (TILs). Breast biomarker results were extracted from pathology reports, and women were included if they had a documented ERBB2 value that was not classified ERBB2-positive. Data were analyzed from February 2023 through January 2024.

Exposure

Clinical and tumor characteristics associated with BC and ERBB2-low or ERBB2-negative status.

Main Outcome and Measures

ERBB2-low was defined as immunohistochemistry score of 1+ or 2+ (negative by in situ hybridization); ERBB2-negative was defined as immunohistochemistry score of 0+. Other data were collected by self-report or extraction from electronic health records, including BC risk factors, tumor characteristics, treatment modality, and survival outcomes, with recurrence-free survival (RFS) as the primary outcome and overall survival (OS) and BC-specific mortality (BCSM) as secondary outcomes. The clinical, pathological, and epidemiological variables were compared between ERBB2-low and ERBB2-negative BC.

Results

Of 2200 eligible patients (all female; with mean [SD] age, 60.4 [11.9] years), 1295 (57.2%) had tumors that were ERBB2-low. Hormone receptors were positive in 1956 patients (88.9%). The sample included 291 Asian patients (13.2%), 166 Black patients (7.5%), 253 Hispanic patients (11.5%), 1439 White patients (65.4%), and 51 patients (2.3%) who identified as other race or ethnicity (eg, American Indian or Alaska Native and Pacific Islander). Within the hormone receptor-negative group, patients whose tumors had ERBB2-low staining, compared with those with ERBB2-negative tumors, had better OS (hazard ratio [HR], 0.54; 95% CI, 0.33-0.91; P = .02), RFS (HR, 0.53; 95% CI, 0.30-0.95; P = .03), and BCSM (HR, 0.43; 95% CI, 0.22-0.84; P = .01). In multivariable survival analysis stratified by hormone receptor status and adjusted for key covariates, patients with ERBB2-low and hormone receptor-negative tumors had lower overall mortality (HR, 0.48; 95% CI, 0.27-0.83; P = .009), RFS (HR, 0.45; 95% CI, 0.24-0.86; P = .02), and BCSM (subdistribution HR, 0.21; 95% CI, 0.10-0.46; P < .001) compared with patients with ERBB2-negative and hormone receptor-negative tumors. Within the hormone receptor-negative subtype, patients with ERBB2-low and high TILs tumors had better survival across all 3 outcomes compared with patients with ERBB2-negative and low TILs tumors. Additionally, patients with ERBB2-low and low TILs tumors had better BCSM (subdistribution HR, 0.36; 95% CI, 0.14-0.92; P = .03).

Conclusions and Relevance

These findings suggest that there were clinical, pathological, and epidemiological differences between ERBB2-low and ERBB2-negative BC, raising the possibility that ERBB2-low might be a unique biologic entity.

Evaluation of Algorithms Using Automated Health Plan Data to Identify Breast Cancer Recurrences

BACKGROUND

We updated algorithms to identify breast cancer recurrences from administrative data, extending previously developed methods.

METHODS

In this validation study, we evaluated pairs of breast cancer recurrence algorithms (vs. individual algorithms) to identify recurrences. We generated algorithm combinations that categorized discordant algorithm results as no recurrence [High Specificity and PPV (positive predictive value) Combination] or recurrence (High Sensitivity Combination). We compared individual and combined algorithm results to manually abstracted recurrence outcomes from a sample of 600 people with incident stage I-IIIA breast cancer diagnosed between 2004 and 2015. We used Cox regression to evaluate risk factors associated with age- and stage-adjusted recurrence rates using different recurrence definitions, weighted by inverse sampling probabilities.

RESULTS

Among 600 people, we identified 117 recurrences using the High Specificity and PPV Combination, 505 using the High Sensitivity Combination, and 118 using manual abstraction. The High Specificity and PPV Combination had good specificity [98%, 95% confidence interval (CI): 97-99] and PPV (72%, 95% CI: 63-80) but modest sensitivity (64%, 95% CI: 44-80). The High Sensitivity Combination had good sensitivity (80%, 95% CI: 49-94) and specificity (83%, 95% CI: 80-86) but low PPV (29%, 95% CI: 25-34). Recurrence rates using combined algorithms were similar in magnitude for most risk factors.

CONCLUSIONS

By combining algorithms, we identified breast cancer recurrences with greater PPV than individual algorithms, without additional review of discordant records.

IMPACT

Researchers should consider tradeoffs between accuracy and manual chart abstraction resources when using previously developed algorithms. We provided guidance for future studies that use breast cancer recurrence algorithms with or without supplemental manual chart abstraction.

Diet quality and cardiovascular disease risk among breast cancer survivors in the Pathways Study

BACKGROUND

Women with breast cancer are at higher risk of cardiovascular disease (CVD) compared with women without breast cancer. Whether higher diet quality at breast cancer diagnosis lowers this risk remains unknown. We set out to determine if higher diet quality at breast cancer diagnosis was related to lower risk of CVD and CVD-related death.

METHODS

This analysis included 3415 participants from the Pathway Study, a prospective cohort of women diagnosed with invasive breast cancer at Kaiser Permanente Northern California between 2005 and 2013 and followed through December 31, 2021. Scores from 5 diet quality indices consistent with healthy eating were obtained at the time of breast cancer diagnosis. Scores were categorized into ascending quartiles of concordance for each diet quality index, and multivariable adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated. P values were 2-sided.

RESULTS

The Dietary Approaches to Stop Hypertension diet quality index was associated with lower risk of heart failure (HR = 0.53, 95% CI = 0.33 to 0.87; Ptrend = .03), arrhythmia (HR = 0.77, 95% CI = 0.62 to 0.94; Ptrend = .008), cardiac arrest (HR = 0.77, 95% CI = 0.61 to 0.96; Ptrend = .02), valvular heart disease (HR = 0.79, 95% CI = 0.64 to 0.98; Ptrend = .046), venous thromboembolic disease (HR = 0.75, 95% CI = 0.60 to 0.93; Ptrend = .01), and CVD-related death (HR = 0.70, 95% CI = 0.50 to 0.99; Ptrend = .04), when comparing the highest with lowest quartiles. Inverse associations were also found between the healthy plant-based dietary index and heart failure (HR = 0.60, 95% CI = 0.39 to 0.94; Ptrend = .02), as well as the alternate Mediterranean dietary index and arrhythmia (HR = 0.74, 95% CI = 0.60 to 0.93; Ptrend = .02).

CONCLUSION

Among newly diagnosed breast cancer patients, higher diet quality at diagnosis was associated with lower risk of CVD events and death.

Assessment of breast cancer chemotherapy dose reduction in an integrated healthcare delivery system

PURPOSE

Most cytotoxic drugs are dosed using body surface area (BSA), yet not all cancer patients receive the full BSA-determined dose. Prior work suggests that breast cancer patients who are obese are more likely to experience dose reduction than normal weight patients. However, the factors driving dose reduction remain unclear.

METHODS

In 452 women diagnosed with stage I-IIIA primary breast cancer at Kaiser Permanente Northern California, we evaluated the association between obesity and dose reduction, and further explored other factors in relation to dose reduction, including various sociodemographic characteristics, tumor characteristics, and comorbidities. Study participants were a part of the Pathways Study, diagnosed between 2006 and 2013 and treated with cyclophosphamide + doxorubicin, followed by paclitaxel (ACT). Dose reduction was assessed using first cycle dose proportion (FCDP) and average relative dose intensity (ARDI), a metric of dose intensity over the course of chemotherapy.

RESULTS

Overall, 8% of participants received a FCDP < 90% and 21.2% had an ARDI < 90%, with dose reduction increasing with body mass index. In adjusted logistic regression models, obese women had 4.1-fold higher odds of receiving an ARDI < 90% than normal weight women (95% CI: 1.9-8.9; p-trend = 0.0006). Increasing age was positively associated with an ADRI < 90%, as was the presence of comorbidity. Dose reduction was less common in later calendar years.

CONCLUSION

Results offer insight on factors associated with chemotherapy dosing for a common breast cancer regimen. Larger studies are required to evaluate relevance to other regimens, and further work will be needed to determine whether dose reductions impact outcomes in obese women.

A polygenic score associated with fracture risk in breast cancer patients treated with aromatase inhibitors

Identifying women at high risk of osteoporotic fracture from aromatase inhibitor (AI) therapy for breast cancer is largely based on known risk factors for healthy postmenopausal women, which might not accurately reflect the risk in breast cancer patients post-AI therapy. To determine whether a polygenic score associated with fracture in healthy women is also significant in women treated with AIs for breast cancer, we used data from a prospective observational cohort of 2152 women diagnosed with hormonal receptor positive breast cancer treated with AIs as the initial endocrine therapy and examined a polygenic score of heel quantitative ultrasound speed of sound (gSOS) in relation to incident osteoporotic fracture after AI therapy during a median 6.1 years of follow up after AI initiation. In multivariable models, patients with the second and third highest tertiles (T) versus the lowest tertile of gSOS had significantly lower risk of fracture (T2: adjusted HR = 0.61, 95% CI: 0.46-0.80; T3: adjusted HR = 0.53, 95% CI: 0.40-0.70). The lower risk of fracture in patients with the highest tertile of gSOS remained significant after further adjustment for BMD at the hip (T3: adjusted HR = 0.62, 95% CI: 0.42-0.91). In conclusion, our analysis showed gSOS as a novel genetic predictor for fracture risk independent of BMD among breast cancer patients treated with AIs. Future studies are warranted to evaluate the performance of incorporating gSOS in prediction models for the risk of AI-related fracture in breast cancer patients.

Alcohol consumption and prognosis and survival in breast cancer survivors: The Pathways Study

BACKGROUND

The impact of alcohol consumption on breast cancer (BC) prognosis remains unclear.

METHODS

The authors examined short-term alcohol intake in relation to recurrence and mortality in 3659 women who were diagnosed with stage I-IV BC from 2003 to 2013 in the Pathways Study. Alcohol drinking in the past 6 months was assessed at cohort entry (mean, 2 months postdiagnosis) and 6 months later using a food-frequency questionnaire. Study end points were recurrence and death from BC, cardiovascular disease, and all causes. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox proportional hazards models.

RESULTS

Over an average follow-up of 11.2 years, 524 recurrences and 834 deaths (369 BC-specific and 314 cardiovascular disease-specific) occurred. Compared with nondrinkers (36.9%), drinkers were more likely younger, more educated, and current or past smokers. Overall, alcohol consumption was not associated with recurrence or mortality. However, women with higher body mass index (BMI ≥ 30 kg/m2 ) had lower risk of overall mortality with increasing alcohol consumption for occasional drinking (HR, 0.71; 95% CI, 0.54-0.94) and regular drinking (HR, 0.77; 95% CI, 0.56-1.08) around the time of diagnosis, along with 6 months later, in a dose-response manner (p < .05). Women with lower BMI (<30 kg/m2 ) were not at higher risk of mortality but were at possibly higher, yet nonsignificant, risk of recurrence for occasional drinking (HR, 1.29; 95% CI, 0.97-1.71) and regular drinking (HR, 1.19; 95% CI, 0.88-1.62).

CONCLUSIONS

Alcohol drinking around the time of and up to 6 months after BC diagnosis was associated with lower risk of all-cause mortality in obese women. A possible higher risk of recurrence was observed in nonobese women.

Environmental and Occupational Exposures and Prognosis in Patients with Non-Muscle Invasive Bladder Cancer in the Be-Well Study

Bladder cancer is primarily diagnosed as non-muscle invasive bladder cancer (NMIBC) with high recurrence and progression rates. Environmental and occupational exposures to carcinogens are well-known risk factors for developing bladder cancer, yet their effects on prognosis remain unknown. In the Be-Well Study, a population-based prospective cohort study of 1,472 patient with newly diagnosed NMIBC from 2015 to 2019, we examined history of environmental and occupational exposures in relation to tumor stage and grade at initial diagnosis by multivariable logistic regression, and subsequent recurrence and progression by Cox proportional hazards regression. Exposure to environmental and occupational carcinogens was significantly associated with increased risk of progression (HR = 1.79; 95% CI: 1.04, 3.09), specifically increased progression into muscle-invasive disease (HR = 2.28; 95% CI: 1.16, 4.50). Exposure to asbestos and arsenic were associated with increased odds of advanced stage at diagnosis (asbestos: OR = 1.43; 95% CI: 1.11, 1.84; arsenic, OR = 1.27; 95% CI: 1.01, 1.63), and formaldehyde exposure was associated with increased risk of recurrence (HR = 1.38; 95% CI: 1.12, 1.69). Our findings suggest that history of these exposures may benefit current risk stratification systems to tailor clinical care and improve prognosis in patients with NMIBC.

Hypothetical Interventions on Diet Quality and Lifestyle Factors to Improve Breast Cancer Survival: The Pathways Study

BACKGROUND

The number of breast cancer survivors is increasing, yet evidence to inform dietary and lifestyle guidelines is limited.

METHODS

This analysis included 3,658 participants from the Pathways Study, a prospective cohort of women diagnosed with invasive breast cancer. A healthy plant-based dietary index score (hPDI), an American Cancer Society (ACS) nutrition guidelines score, a 2015 Healthy Eating Index score (HEI), hours per week of moderate to vigorous physical activity (PA), and lifetime cumulative pack-years of cigarette smoking (SM) were each measured at diagnosis, 6, 24, and 72 months. Using g-computation, 5- and 10-year risk ratios (RR), risk differences, and 95% confidence intervals (CI) for all-cause mortality under hypothetical interventions on diet quality, PA, and SM, compared with the natural course (no intervention) were calculated.

RESULTS

Hypothetical moderate to extreme interventions on hPDI, ACS, and HEI, each in combination with PA and SM, showed 11% to 56%, 9% to 38%, and 9% to 49% decreases in 5-year risks of all-cause mortality compared with no intervention, respectively [(hPDI: RRmoderate = 0.89, 95% CI: 0.82-0.94; RRextreme = 0.44, 95% CI: 0.26-0.67), (ACS: RRmoderate = 0.91, 95% CI: 0.85-0.96; RRextreme = 0.62, 95% CI: 0.43-0.82), (HEI: RRmoderate = 0.91, 95% CI: 0.84-0.95; RRextreme = 0.51, 95% CI: 0.33-0.72)]. While 10-year relative risks were slightly attenuated, absolute risk reductions were more pronounced.

CONCLUSIONS

Interventions to improve diet quality, increase PA, or reduce SM at the time of diagnosis may improve survival among breast cancer survivors.

IMPACT

We estimate that over 10% of deaths could be delayed by even moderate adoption of these behaviors.

Development of cardiometabolic risk factors following endocrine therapy in women with breast cancer

PURPOSE

Studies comparing the effect of aromatase inhibitor (AI) and tamoxifen use on cardiovascular disease (CVD) risk factors in hormone receptor-positive breast cancer (BC) survivors report conflicting results. We examined associations of endocrine therapy use with incident diabetes, dyslipidemia, and hypertension.

METHODS

The Pathways Heart Study examines cancer treatment exposures with CVD-related outcomes in Kaiser Permanente Northern California members with BC. Electronic health records provided sociodemographic and health characteristics, BC treatment, and CVD risk factor data. Hazard ratios (HR) and 95% confidence intervals (CI) of incident diabetes, dyslipidemia, and hypertension in hormone receptor-positive BC survivors using AIs or tamoxifen compared with survivors not using endocrine therapy were estimated using Cox proportional hazards regression models adjusted for known confounders.

RESULTS

In 8985 BC survivors, mean baseline age and follow-up time was 63.3 and 7.8 years, respectively; 83.6% were postmenopausal. By treatment, 77.0% used AIs, 19.6% used tamoxifen, and 16.0% used neither. Postmenopausal women who used tamoxifen had an increased rate (HR 1.43, 95% CI 1.06-1.92) of developing hypertension relative to those who did not use endocrine therapy. Tamoxifen use was not associated with incident diabetes, dyslipidemia, or hypertension in premenopausal BC survivors. Postmenopausal AI users had higher hazard rates of developing diabetes (HR 1.37, 95% CI 1.05-1.80), dyslipidemia (HR 1.58, 95% CI 1.29-1.92), and hypertension (HR 1.50, 95% CI 1.24-1.82) compared with non-endocrine therapy users.

CONCLUSION

Hormone receptor-positive BC survivors treated with AIs may have higher rates of developing diabetes, dyslipidemia, and hypertension over an average 7.8 years post-diagnosis.

Neighborhood attributes and cardiovascular disease risk in breast cancer survivors: The Pathways Study

BACKGROUND

Breast cancer survivors are at a higher risk of cardiovascular disease (CVD) morbidity and mortality compared with the general population. The impact of objective social and built neighborhood attributes on CVD risk in a cohort of female breast cancer survivors was examined.

METHODS

The 3975 participants came from the Pathways Study, a prospective cohort of women with invasive breast cancer from an integrated health care system in northern California. Women diagnosed with breast cancer from 2006 through 2013 were enrolled on average approximately 2 months after diagnosis. Their baseline addresses were geocoded and appended to neighborhood attributes for racial/ethnic composition, socioeconomic status (SES), population density, urbanization, crime, traffic density, street connectivity, parks, recreational facilities, and retail food environment. Incident CVD events included ischemic heart disease, heart failure, cardiomyopathy, or stroke. Cox proportional hazards models estimated associations of neighborhood attributes with CVD risk, which accounted for clustering by block groups. Fully adjusted models included sociodemographic, clinical, and behavioral factors.

RESULTS

During follow-up through December 31, 2018, 340 participants (8.6%) had CVD events. A neighborhood racial/ethnic composition measure, percent of Asian American/Pacific Islander residents (lowest quintile hazard ratio [HR], 1.85; 95% CI, 1.03-3.33), and crime index (highest quartile HR, 1.48; 95% CI, 1.08-2.03) were associated with the risk of CVD events independent of individual SES, hormone receptor status, treatment, cardiometabolic comorbidities, body mass index, and physical activity.

CONCLUSIONS

With the application of a socio-ecological framework, how residential environments shape health outcomes in women with breast cancer and affect CVD risk in this growing population can be understood.

Associations of Post-Diagnosis Lifestyle with Prognosis in Women with Invasive Breast Cancer

BACKGROUND

Lifestyle habits can impact breast cancer development, but its impact on breast cancer prognosis remains unclear. We investigated associations of post-diagnosis lifestyle with mortality and recurrence in 1,964 women with invasive breast cancer enrolled in the Kaiser Permanente Northern California Pathways Study shortly after diagnosis with lifestyle information at baseline (2005-2013) and the 2-year follow-up.

METHODS

We calculated a post-diagnosis lifestyle score (range, 0-18) based on 9 diet, physical activity, and body weight recommendations from the American Cancer Society/American Society of Clinical Oncology (ACS/ASCO) using follow-up data (body weight also included baseline data); higher scores indicate greater guideline concordance. Similarly, we calculated a pre-diagnosis lifestyle score using baseline data to investigate pre- to post-diagnosis changes. We estimated hazard ratios (HR) and 95% confidence intervals (CI) using Cox proportional hazard models, with follow-up through December 2018 (observing 290 deaths and 176 recurrences).

RESULTS

The 2-year post-diagnosis lifestyle score was inversely associated with all-cause mortality (ACM; HR per 2-point increase = 0.90; 95% CI, 0.82-0.98), and breast cancer-related mortality (HR, 0.79; 95% CI, 0.67-0.95), but not recurrence. Relative to women who maintained low concordance with recommendations at both time points, women who maintained high concordance had a lower risk of ACM (HR, 0.61, 95% CI, 0.37-1.03). Improved concordance with some specific recommendations (particularly PA) may be associated with a lower hazard of ACM (HRPA, 0.52; 95% CI, 0.35-0.78).

CONCLUSIONS

Results suggest that women with breast cancer may benefit from a post-diagnosis lifestyle aligned with ACS/ASCO guidelines.

IMPACT

This information may potentially guide lifestyle recommendations for breast cancer survivors to reduce mortality risk.

Associations of dietary isothiocyanate exposure from cruciferous vegetable consumption with recurrence and progression of non-muscle-invasive bladder cancer: findings from the Be-Well Study

BACKGROUND

High recurrence and progression rates are major clinical challenges for non-muscle-invasive bladder cancer (NMIBC). Dietary isothiocyanates (ITCs), phytochemicals primarily from cruciferous vegetables (CV), show strong anticancer activities in preclinical BC models, yet their effect on NMIBC prognosis remains unknown.

OBJECTIVES

This study aimed to investigate the associations of dietary ITC exposure at diagnosis with NMIBC recurrence and progression.

METHODS

The study analyzed 1143 participants from the Be-Well study, a prospective cohort of newly diagnosed NMIBC cases in 2015-2019 with no prior history of BC. Dietary ITC exposure was indicated by self-reported CV intake, estimated ITC intake, urinary metabolites, and plasma ITC-albumin adducts. Cox proportional hazards regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for recurrence and progression, and unconditional logistic regression models were used to calculate odds ratios (ORs) and 95% CIs for delayed and multiple recurrence.

RESULTS

Over a mean follow-up of 25 mo, 347 (30%) developed recurrence and 77 (6.7%) had disease progression. Despite no significant associations with the overall risk of recurrence, urinary ITC metabolites (OR: 1.96; 95% CI: 1.01, 4.43) and dietary ITC intake (OR: 2.13; 95% CI: 1.03, 4.50) were associated with late recurrence after 12-mo postdiagnosis compared with before 12-mo postdiagnosis. Raw CV intake was associated with reduced odds of having ≥2 recurrences compared with having one (OR: 0.34; 95% CI: 0.16, 0.68). Higher plasma concentrations of ITC-albumin adducts were associated with a reduced risk of progression, including progression to muscle-invasive disease (for benzyl ITC, HR: 0.40; 95% CI: 0.17, 0.93; for phenethyl ITC, HR: 0.40; 95% CI: 0.19, 0.86).

CONCLUSIONS

Our findings indicate the possible beneficial role of dietary ITCs in NMIBC prognosis. Given the compelling preclinical evidence, increasing dietary ITC exposure with CV intake could be a promising strategy to attenuate recurrence and progression risks in patients with NMIBC.

A Mendelian Randomization Analysis of 55 Genetically Predicted Metabolic Traits with Breast Cancer Survival Outcomes in the Pathways Study

Previous studies suggest associations of metabolic syndromes with breast cancer prognosis, yet the evidence is mixed. In recent years, the maturation of genome-wide association study findings has led to the development of polygenic scores (PGS) for many common traits, making it feasible to use Mendelian randomization to examine associations between metabolic traits and breast cancer outcomes. In the Pathways Study of 3,902 patients and a median follow-up time of 10.5 years, we adapted a Mendelian randomization approach to calculate PGS for 55 metabolic traits and tested their associations with seven survival outcomes. Multivariable Cox proportional hazards models were used to derive HRs and 95% confidence intervals (CI) with adjustment for covariates. The highest tertile (T3) of PGS for cardiovascular disease was associated with shorter overall survival (HR = 1.34, 95% CI = 1.11-1.61) and second primary cancer-free survival (HR = 1.31, 95% CI = 1.12-1.53). PGS for hypertension (T3) was associated with shorter overall survival (HR = 1.20, 95% CI = 1.00-1.43), second primary cancer-free survival (HR = 1.24, 95% CI = 1.06-1.45), invasive disease-free survival (HR = 1.18, 95% CI = 1.01-1.38), and disease-free survival (HR = 1.21, 95% CI = 1.04-1.39). PGS for serum cystatin C levels (T3) was associated with longer disease-free survival (HR = 0.82, 95% CI = 0.71-0.95), breast event-free survival (HR = 0.74, 95% CI = 0.61-0.91), and breast cancer-specific survival (HR = 0.72, 95% CI = 0.54-0.95). The above associations were significant at a nominal P < 0.05 level but not after correcting for multiple testing (Bonferroni P < 0.0009). Our analyses revealed notable associations of PGS for cardiovascular disease, hypertension, and cystatin C levels with breast cancer survival outcomes. These findings implicate metabolic traits in breast cancer prognosis.

Significance

To our knowledge, this is the largest study of PGS for metabolic traits with breast cancer prognosis. The findings revealed significant associations of PGS for cardiovascular disease, hypertension, and cystatin C levels with several breast cancer survival outcomes. These findings implicate an underappreciated role of metabolic traits in breast cancer prognosis that would warrant further exploration.

Development of cardiometabolic risk factors following endocrine therapy in women with breast cancer

PURPOSE

Studies comparing the effect of aromatase inhibitor (AI) and tamoxifen use on cardiovascular disease (CVD) risk factors in hormone-receptor positive breast cancer (BC) survivors report conflicting results. We examined associations of endocrine therapy use with incident diabetes, dyslipidemia, and hypertension.

METHODS

The Pathways Heart Study examines cancer treatment exposures with CVD-related outcomes in Kaiser Permanente Northern California members with BC. Electronic health records provided sociodemographic and health characteristics, BC treatment, and CVD risk factor data. Hazard ratios (HR) and 95% confidence intervals (CI) of incident diabetes, dyslipidemia, and hypertension in hormone-receptor positive BC survivors using AIs or tamoxifen compared with survivors not using endocrine therapy were estimated using Cox proportional hazards regression models adjusted for known confounders.

RESULTS

In 8,985 BC survivors, mean baseline age and follow-up time was 63.3 and 7.8 years, respectively; 83.6% were postmenopausal. By treatment, 77.0% used AIs, 19.6% used tamoxifen, and 16.0% used neither. Postmenopausal women who used tamoxifen had an increased rate (HR: 1.43, 95% CI: 1.06-1.92) of developing hypertension relative to those who did not use endocrine therapy. Tamoxifen use was not associated with incident diabetes, dyslipidemia, or hypertension in premenopausal BC survivors. Postmenopausal AI users had higher hazard rates of developing diabetes (HR: 1.37, 95% CI: 1.05-1.80), dyslipidemia (HR: 1.58, 95% CI: 1.29-1.92) and hypertension (HR: 1.50, 95% CI: 1.24-1.82) compared with non-endocrine therapy users.

CONCLUSION

Hormone-receptor positive BC survivors treated with AIs may have higher rates of developing diabetes, dyslipidemia, and hypertension over an average 7.8 years post-diagnosis.

Abstract P3-03-16: A methodology for using real-world data from electronic health records to assess chemotherapy administration in women with breast cancer

Introduction Chemotherapy administration in real-world cancer care can differ extensively from clinical trials. It is important to understand real-world practice to identify dose reductions, delays, regimen changes and early discontinuations that impact cancer outcomes. Such variables require knowledge of intended regimens, which may not be well-documented in structured data in electronic health records (EHRs). We examined EHR data from the Kaiser Permanente Northern California (KPNC) site of the Optimal Breast Cancer Chemotherapy Dosing (OBCD) study to develop a process to identify each patient’s intended regimen. Methods In this study of women diagnosed and treated with primary stage I-IIIA breast cancer at KPNC from 2006-2019, and ages 18+y at diagnosis, we analyzed treatment patterns using structured EHR data on the drugs, dosages, and dates at which they were administered (from which intervals and total length can be derived). Chemotherapy agents were identified using the NCI’s CANMED database augmented with other sources. We used these data to categorize patients into the 22 drug combinations described in the National Cancer Care Network (NCCN) guidelines for breast cancer treatment. Within these 22 drug combinations, women were then subcategorized into 45 distinct chemotherapy administration schedules, defined as NCCN guideline regimens (NGRs). For this step, algorithms were developed that categorized patients into NGRs if they received the exact regimen described in the guidelines. For the second step, we conducted a manual review of the EHR data for patients who were unable to be categorized. This enabled us to gradually loosen the criteria (in terms of cycle intervals or number of cycles) so patients whose chemotherapy administration aligned closely with NGRs were categorized into each of the 45 NGRs. Clear patterns emerged of regimens that were administered to multiple patients, despite being outside of the NCCN guidelines, which we have defined as non-standard NGRs. For example, in the drug combination TC (cyclophosphamide and docetaxel) the NGR was TC every 21 days for 4 cycles. We found approximately 1 in 10 patients received 6 cycles, which we defined as a non-NGR. For the remaining uncategorized patients, medical chart abstraction was undertaken as a third step, at which point patients were categorized into either existing regimens or new non-NGRs if their intended regimen had not been previously described in the guidelines. Results Among 31,418 women with breast cancer, 12,427 (39.6%) received chemotherapy. We determined the intended chemotherapy regimens for 6,559 (52.8%) receiving the 45 NGRs using EHR data. We further expanded the algorithms through a manual review of the EHR data, which enabled us to categorize 2,977 (24.0%) additional women into their intended regimens. Abstracted medical notes were reviewed for the remaining patients for whom we had not been able to identify the intended regimen. Across both the manual review and abstraction processes, we were able to identify additional non-standard NGR regimens. In total, 9,536 (76.7%) of women were categorized into their intended regimen through the algorithm/manual review process, while 2891 (23.3%) of women underwent medical chart abstraction to identify the intended regimen. Conclusion Here, we describe the challenges and approaches to operationalize complex, real-world data to identify intended chemotherapy regimens at a granularity and scale not seen previously. We are adapting this method at a second OBCD study site, Kaiser Permanente Washington, where all women have undergone medical chart abstraction. We hope this methodology leads to increased feasibility and efficiency of use of large-scale clinical data, in turn improving cancer care delivery, patient outcome evaluation, and other real-world questions.

Citation Format: Jenna Bhimani, Kelli O’Connell, Rachael P. Burganowski, Isaac J. Ergas, Marilyn J. Foley, Grace B. Gallagher, Jennifer J. Griggs, Narre Heon, Tatjana Kolevska, Yuriy Kotsurovskyy, Candyce H. Kroenke, Kanichi G. Nakata, Sonia Persaud, Donna R. Rivera, Janise M. Roh, Sara Tabatabai, Emily Valice, Erin J. Bowles, Elisa V. Bandera, Lawrence H. Kushi, Elizabeth D. Kantor. A methodology for using real-world data from electronic health records to assess chemotherapy administration in women with breast cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-03-16.

Impact of Racial/Ethnic Discrimination on Quality of Life Among Breast Cancer Survivors

Although racial/ethnic disparities in health-care access, treatment, and cancer outcomes are well documented, the impact of racial/ethnic discrimination on cancer survivorship is unclear. We examined associations between quality of life (QoL) and self-reported discrimination among 3,991 women with breast cancer recruited during 2006-2013 from the Pathways Study in the Kaiser Permanente Northern California integrated health-care system, using linear regression models. Overall, 31% of women reported experiencing racial/ethnic discrimination, with differences by race/ethnicity (82% among non-Hispanic Black women vs. 19% among non-Hispanic White women) and nativity (40% among foreign-born Hispanic women vs. 76% among US-born Asian-American women). Experiencing racial/ethnic discrimination was associated with lower QoL in fully adjusted models. The mean QoL score was 119.6 (95% confidence interval (CI): 102.0, 137.1) for women who did not report discrimination, 115.5 (95% CI: 98.0, 133.0) for those who reported some discrimination/less than the median level, and 110.2 (95% CI: 92.7, 127.7) for those who reported more discrimination/greater than or equal to the median level. Discrimination was associated with lower QoL among women who used passive coping strategies or lived in neighborhoods with high neighborhood socioeconomic status, neighborhoods with high levels of segregation, or non-ethnic enclaves. Among breast cancer survivors, clinically meaningful differences in QoL scores were associated with racial/ethnic discrimination. Additional studies are needed to understand potential pathways through which these social factors affect survivorship outcomes.

A prospective study of lifestyle factors and bone health in breast cancer patients who received aromatase inhibitors in an integrated healthcare setting

PURPOSE

Fracture and osteoporosis are known side effects of aromatase inhibitors (AIs) for postmenopausal hormone receptor positive (HR+) breast cancer (BC) patients. How modifiable lifestyle factors impact fracture risk in these patients is relatively unknown.

METHODS

We conducted a prospective cohort study to examine the association of lifestyle factors, focusing on physical activity, with risk of incident major osteoporotic fracture and osteoporosis in 2152 HR+ BC patients diagnosed from 2006 to 2013 at Kaiser Permanente Northern California and who received AIs. Patients self-reported lifestyle factors at study entry and at 6-month follow-up. Fracture and osteoporosis outcomes were prospectively ascertained by physician-adjudication and bone mineral density (BMD) values, respectively. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated from multivariable proportional hazards regression. Models were adjusted for age, menopausal status, race/ethnicity, body mass index (BMI), AJCC stage, breast cancer treatment, prior osteoporosis, and prior major fracture.

RESULTS

Over a median 6.1 years of follow-up after AI initiation, 165 women experienced an incident osteoporotic fracture and 243 women had osteoporosis. No associations were found between overall moderate-vigorous physical activity and fracture risk, although < 150 min/week of aerobic exercise in the 6 months after BC diagnosis was associated with increased fracture risk (HR=2.42; 95% CI: 1.34, 4.37) compared with ≥ 150 min/week (meeting physical activity guidelines). Risk was also higher for never or infrequently engaging in aerobic exercise (HR=1.90; 95% CI: 1.05, 3.44). None or infrequent overall moderate-vigorous physical activity in the 6 months before BC diagnosis was associated with increased risk of osteoporosis (HR=1.94; 95% CI: 1.11; 3.37).

CONCLUSIONS

Moderate-vigorous physical activity during the immediate period after BC diagnosis, particularly aerobic exercise, was associated with lower risk of major osteoporotic fractures in women on AI therapy.

IMPLICATIONS FOR CANCER SURVIVORS

Findings may inform fracture prevention in women on AI therapy through non-pharmacologic lifestyle-based strategies.

Smoking Behaviors and Prognosis in Patients With Non-Muscle-Invasive Bladder Cancer in the Be-Well Study

Importance

Tobacco smoking is an established risk factor associated with bladder cancer, yet its impact on bladder cancer prognosis is unclear.

Objective

To examine associations of use of tobacco (cigarettes, pipes, and cigars), e-cigarettes, and marijuana with risk of recurrence and progression of non-muscle-invasive bladder cancer (NMIBC) and to explore use of smoking cessation interventions.

Design, Setting, and Participants

The Be-Well Study is a prospective cohort study of patients with NMIBC diagnosed from 2015 to 2019 and followed-up for 26.4 months in the Kaiser Permanente Northern and Southern California integrated health care system. Eligibility criteria were age at least 21 years, first NMIBC diagnosis (stages Ta, Tis, or T1), alive, and not in hospice care. Exclusion criteria were previous diagnosis of bladder cancer or other cancer diagnoses within 1 year prior to or concurrent with NMIBC diagnosis. Data were analyzed from April 1 to October 4, 2022.

Exposures

Use of cigarettes, pipes, cigars, e-cigarettes, and marijuana was reported in the baseline interview. Use of smoking cessation interventions (counseling and medications) was derived from electronic health records.

Main Outcomes and Measures

Hazard ratios (HRs) and 95% CIs of recurrence and progression of bladder cancer were estimated by multivariable Cox proportional hazards regression.

Results

A total of 1472 patients (mean [SD] age at diagnosis, 70.2 [10.8%] years; 1129 [76.7%] male patients) with NMIBC were enrolled at a mean (SD) of 2.3 (1.3) months after diagnosis, including 874 patients (59.4%) who were former smokers and 111 patients (7.5%) who were current cigarette smokers; 67 patients (13.7%) smoked pipes and/or cigars only, 65 patients (4.4%) used e-cigarettes, 363 patients (24.7%) used marijuana. Longer cigarette smoking duration and more pack-years were associated with higher risk of recurrence in a dose-dependent manner, with the highest risks for patients who had smoked for 40 or more years (HR, 2.36; 95% CI, 1.43-3.91) or 40 or more pack-years (HR, 1.97; 95% CI, 1.32-2.95). There was no association of having ever smoked, being a former or current cigarette smoker, and years since quit smoking with recurrence risk. No associations with pipes, cigars, e-cigarettes, or marijuana were found. Of 102 patients offered a smoking cessation intervention, 57 (53.8%) received an interventions after diagnosis, with female patients more likely than male patients to engage in such interventions (23 of 30 female patients [76.7%] vs 34 of 76 male patients [44.7%]; P = .003).

Conclusions and Relevance

These findings suggest that longer duration and more pack-years of cigarette smoking were associated with higher risk of NMIBC recurrence. Cigarette smoking remains a critical exposure before and after diagnosis in survivors of NMIBC.

Results and lessons from dual extraction of DNA and RNA from formalin-fixed paraffin-embedded breast tumor tissues for a large Cancer epidemiologic study

BACKGROUND

The use of archived formalin-fixed paraffin-embedded (FFPE) tumor tissues has become a common practice in clinical and epidemiologic genetic research. Simultaneous extraction of DNA and RNA from FFPE tissues is appealing but can be practically challenging. Here we report our results and lessons learned from processing FFPE breast tumor tissues for a large epidemiologic study.

METHODS

Qiagen AllPrep DNA/RNA FFPE kit was adapted for dual extraction using tissue punches or sections from breast tumor tissues. The yield was quantified using Qubit and fragmentation analysis by Agilent Bioanalyzer. A subset of the DNA samples were used for genome-wide DNA methylation assays and RNA samples for sequencing. The QC metrices and performance of the assays were analyzed with pre-analytical variables.

RESULTS

A total of 1859 FFPE breast tumor tissues were processed. We found it critical to adjust proteinase K digestion time based on tissue volume to achieve balanced yields of DNA and RNA. Tissue punches taken from tumor-enriched regions provided the most reliable output. A median of 1475 ng DNA and 1786 ng RNA per sample was generated. The median DNA integrity number (DIN) was 3.8 and median DV200 for RNA was 33.2. Of 1294 DNA samples used in DNA methylation assays, 97% passed quality check by qPCR and 92% generated data deemed high quality. Of the 130 RNA samples with DV200 ≥ 20% used in RNA-sequencing, all but 5 generated usable transcriptomic data with a mapping rate ≥ 60%.

CONCLUSIONS

Dual DNA/RNA purification using Qiagen AllPrep FFPE extraction protocol is feasible for clinical and epidemiologic studies. We recommend tissue punches as a reliable source material and fine tuning of proteinase K digestion time based on tissue volume.

IMPACT

Our protocol and recommendations may be adapted by future studies for successful extraction of archived tumor tissues.

Abstract 5303: Cardiovascular disease risk associated with breast cancer chemotherapy drugs: The Pathways Heart Study

Purpose: Chemotherapy drugs to treat breast cancer (BC) are cardiotoxic, but few studies have examined the effects of specific chemotherapy combinations on cardiovascular disease (CVD). We examined the additive effects of combinations of BC chemotherapy drugs associated with incident CVD events among women with a history of BC compared to those without.

Methods: The Pathways Heart Study is a cohort study within Kaiser Permanente Northern California (KPNC) examining incident CVD events and risk factors in women with BC. Eligibility criteria included invasive BC diagnosis from 11/2005 to 3/2013, age&ge;21 years, and KPNC membership&ge;12 months at BC diagnosis. Controls without BC were matched 5:1 on birth year and race/ethnicity. KPNC electronic health records were used to collect demographic, clinical, and treatment characteristics. Chemotherapy drugs identified from clinical data included anthracyclines, cyclophosphamides, taxanes, and trastuzumab. Mutually exclusive groups were created according to the types of chemotherapy drugs received. Outcomes identified from ICD9/10 diagnosis codes included incident ischemic heart disease, heart failure (HF)/cardiomyopathy and stroke. Multivariable Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) of the CVD outcome by chemotherapy drug combinations received relative to matched controls.

Results: A total of 6,761 women with BC who received chemotherapy were identified and were matched to 33,801 controls. On average, women were 55.2 years old (standard deviation (SD)=10.9) and were followed for 7.1 years (SD=3.6). Four groups of women with distinct chemotherapy combinations were identified: anthracyclines + cyclophosphamide (AC, 10.5%), AC + taxanes (39.0%), AC + taxanes + trastuzumab (8.8%), and cyclophosphamide + taxanes (20.7%). Women who received AC had a 2.00 (95% CI: 1.27-3.14) increased risk of incident HF/cardiomyopathy relative to matched controls without BC. When taxanes were added to this combination, risk was similar (HR=1.88; 95% CI: 1.44-2.47). However, when trastuzumab was further added, risk of HF/cardiomyopathy increased more than 1.5-fold (HR=3.18; 95% CI: 1.91-5.30). The combined receipt of cyclophosphamide and taxanes was associated with a 1.42 (95% CI: 1.05-1.92) increased risk of developing stroke, but including anthracyclines with this combination inversed the association for stroke (HR: 0.73, 95% CI: 0.54- 0.99). No combinations examined were associated with incidence of ischemic heart disease.

Conclusion: Findings suggest specific chemotherapy drug combinations may differentially affect the risk of incident HF/cardiomyopathy and stroke in BC survivors. Future work will examine dosage and duration of chemotherapy exposure, comparisons of the groups’ characteristics to account for possible confounding by indication, and competing risk analysis.

Citation Format: Hanjie Shen, Eileen Rillamas-Sun, Carlos Iribarren, Richard Cheng, Jamal S. Rana, Mai Nguyen-Huynh, Cecile A. Laurent, Valerie S. Lee, Janise M. Roh, Dawn L. Hershman, Lawrence H. Kushi, Marilyn L. Kwan, Heather Greenlee. Cardiovascular disease risk associated with breast cancer chemotherapy drugs: The Pathways Heart Study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5303.

Risk of heart failure with preserved versus reduced ejection fraction in women with breast cancer

PURPOSE

While clinical heart failure (HF) is recognized as an adverse effect from breast cancer (BC) treatment, sparse data exist on specific HF phenotypes in affected BC survivors. We examined risk of HF by left ventricular ejection fraction (LVEF) status in women with a history of BC.

METHODS

14,804 women diagnosed with all stages of invasive BC from 2005 to 2013 and with no history of HF were matched 1:5 to 74,034 women without BC on birth year, race, and ethnicity. LVEF values were extracted from echocardiography studies within 30 days before through 90 days after the HF clinical encounter. HF was stratified into HF with preserved ejection fraction (HFpEF, LVEF ≥ 45%) and HF with reduced ejection fraction (HFrEF, LVEF < 45%). Cumulative incidence rates (CIRs) were estimated with competing risk of overall death. Hazard ratios (HR) were calculated by multivariable Cox proportional hazards regression.

RESULTS

Mean time to HF diagnosis was 5.31 years (range 0.03-13.03) in cases and 5.25 years (range 0.01-12.94) in controls. 10-year CIRs were 1.2% and 0.9% for overall HF, 0.8% and 0.7% for HFpEF, and 0.4% and 0.2% for HFrEF in cases and controls, respectively. In fully adjusted models, an overall significant increased risk of HF in cases versus controls was observed (HR: 1.31, 95% CI 1.14, 1.51). The increased risk was seen for both HFrEF (HR: 1.59, 95% CI 1.22, 2.08) and HFpEF (HR: 1.22; 95% CI 1.03, 1.45).

CONCLUSION

BC survivors experienced higher risk of HF compared with women without BC, and the risk persisted across LVEF phenotypes. Systematic cardio-oncology surveillance should be considered to mitigate this risk in BC patients.

Risk of Cardiovascular Disease in Women With and Without Breast Cancer: The Pathways Heart Study

PURPOSE

To examine cardiovascular disease (CVD) and mortality risk in women with breast cancer (BC) by cancer therapy received relative to women without BC.

METHODS

The study population comprised Kaiser Permanente Northern California members. Cases with invasive BC diagnosed from 2005 to 2013 were matched 1:5 to controls without BC on birth year and race/ethnicity. Cancer treatment, CVD outcomes, and covariate data were from electronic health records. Multivariable Cox proportional hazards models estimated hazard ratios (HRs) and 95% CIs of CVD incidence and mortality by receipt of chemotherapy treatment combinations, radiation therapy, and endocrine therapy.

RESULTS

A total of 13,642 women with BC were matched to 68,202 controls without BC. Over a 7-year average follow-up (range < 1-14 years), women who received anthracyclines and/or trastuzumab had high risk of heart failure/cardiomyopathy relative to controls, with the highest risk seen in women who received both anthracyclines and trastuzumab (HR, 3.68; 95% CI, 1.79 to 7.59). High risk of heart failure and/or cardiomyopathy was also observed in women with BC with a history of radiation therapy (HR, 1.38; 95% CI, 1.13 to 1.69) and aromatase inhibitor use (HR, 1.31; 95% CI, 1.07 to 1.60), relative to their controls. Elevated risks for stroke, arrhythmia, cardiac arrest, venous thromboembolic disease, CVD-related death, and death from any cause were also observed in women with BC on the basis of cancer treatment received.

CONCLUSION

Women with BC had increased incidence of CVD events, CVD-related mortality, and all-cause mortality compared with women without BC, and risks varied according to the history of cancer treatment received. Studies are needed to determine how women who received BC treatment should be cared for to improve cardiovascular outcomes.

UACA locus is associated with breast cancer chemoresistance and survival

Few germline genetic variants have been robustly linked with breast cancer outcomes. We conducted trans-ethnic meta genome-wide association study (GWAS) of overall survival (OS) in 3973 breast cancer patients from the Pathways Study, one of the largest prospective breast cancer survivor cohorts. A locus spanning the UACA gene, a key regulator of tumor suppressor Par-4, was associated with OS in patients taking Par-4 dependent chemotherapies, including anthracyclines and anti-HER2 therapy, at a genome-wide significance level (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$P = 1.27 \times 10^{ - 9}$$\end{document}P=1.27×10−9). This association was confirmed in meta-analysis across four independent prospective breast cancer cohorts (combined hazard ratio = 1.84, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$P = 1.28 \times 10^{ - 11}$$\end{document}P=1.28×10−11). Transcriptome-wide association study revealed higher UACA gene expression was significantly associated with worse OS (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$P = 4.68 \times 10^{ - 7}$$\end{document}P=4.68×10−7). Our study identified the UACA locus as a genetic predictor of patient outcome following treatment with anthracyclines and/or anti-HER2 therapy, which may have clinical utility in formulating appropriate treatment strategies for breast cancer patients based on their genetic makeup.

Abstract PD5-03: Development of cardiometabolic risk factors following endocrine therapy: The pathways heart study

Purpose: Endocrine therapy is associated with cardiovascular disease among breast cancer (BC) survivors, with observed opposing effects between aromatase inhibitors (AIs) and tamoxifen. AIs deplete endogenous estrogen levels, while tamoxifen has mixed estrogenic and antiestrogenic activity. Yet, observational studies comparing AI vs. tamoxifen use may be confounded by indication and few have tested their associations with cardiometabolic risk factors. Therefore, we examined the association of AI or tamoxifen use on the incidence of newly diagnosed hypertension, diabetes, and dyslipidemia in a cohort of BC survivors within Kaiser Permanente Northern California (KPNC). Methods: The Pathways Heart Study is an ongoing cohort study within KPNC examining incident CVD outcomes and risk factors in 14,942 women with history of BC. Eligibility was: 1) stage I-IV invasive BC diagnosis between Nov 2005 and Mar 2013; 2) &ge;21 years; and 3) active KPNC membership &ge;12 months at diagnosis. KPNC records were used to collect demographic, socioeconomic, and health characteristics. Endocrine therapy was collected from outpatient pharmacy data. Incident hypertension, diabetes, and dyslipidemia were identified from ICD-9/10 codes, laboratory results, and/or medication use. Hazard ratios (HR) and 95% confidence intervals (CI) from Cox proportional models were used to determine whether AI and tamoxifen use were associated with incident hypertension, diabetes, and dyslipidemia compared to BC survivors not receiving either of these therapies. For each cardiometabolic risk factor, models adjusted for demographic, socioeconomic, and health characteristics and excluded women with the cardiometabolic risk factor at baseline. Results: Among 14,942 women with a history of BC, mean age at baseline was 61.2±12.8 years and mean follow-up time was 7.0±3.5 years (range 1-13.4). The frequency of use was: AI, n=6,070 (40.6%); tamoxifen, n=1,755 (11.8%); and neither, n=7,117 (47.6%). Regression models showed AI use was associated with increased risk of incident hypertension (HR: 1.1, 95% CI: 1.00-1.21) and increased risk of incident dyslipidemia (HR: 1.18, 95% CI: 1.07-1.3) relative to BC survivors who did not use endocrine therapy. (Table). In contrast, tamoxifen use was associated with decreased risk of dyslipidemia (HR: 0.8, 95% CI: 0.68-0.94) relative to BC survivors who did not use endocrine therapy. Neither AI nor tamoxifen use was associated with risk of incident diabetes. Conclusion: Compared to BC survivors who did not use endocrine therapy, women treated with AIs had a higher risk of incident hypertension and dyslipidemia, while women treated with tamoxifen had a lower risk of dyslipidemia. AIs reduce endogenous estrogen levels, which can alter lipid profiles, although prior studies have been inconsistent, possibly due to differences in steroidal and non-steroidal AIs. More work is needed to understand the implications of these associations on long-term cardiovascular health and how to best manage cardiometabolic risk factors in BC survivors with a history of endocrine therapy use.

Table. Adjusted1 hazard ratios (95% confidence intervals) of incident cardiometabolic risk factors among women with a history of breast cancer, by endocrine therapy useNo Endocrine Therapy(n=7,117)Endocrine TherapyAromatase inhibitor(n=6,070)Tamoxifen(n=1,755)Incident HypertensionRef1.10 (1.00, 1.21)0.98 (0.85, 1.14)Incident DiabetesRef0.99 (0.87, 1.13)0.98 (0.80, 1.20)Incident DyslipidemiaRef1.18 (1.07, 1.30)0.80 (0.68, 0.94)1Adjusted for age, race/ethnicity, baseline body mass index, AJCC stage, menopausal status, smoking status, education level, income, chemotherapy, radiation therapy, and prevalent cardiovascular disease.

Citation Format: Heather Greenlee, Eileen Rillamas-Sun, Carlos Iribarren, Richard Cheng, Romain Neugebauer, Jamal S. Rana, Mai Nguyen-Huynh, Zaixing Shi, Cecile A. Laurent, Valerie S. Lee, Janise M. Roh, Hanjie Shen, Dawn L. Hershman, Lawrence H. Kushi, Marilyn L. Kwan. Development of cardiometabolic risk factors following endocrine therapy: The pathways heart study [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD5-03.

Abstract PD5-01: Cardiovascular disease risk of breast cancer therapies: The pathways heart study

Purpose: Studies on long-term cardiovascular disease (CVD) risk in breast cancer (BC) survivors are limited. We examined CVD risk associated with exposure to specific BC therapies and explored whether body mass index (BMI) or prevalent CVD risk factors at BC diagnosis modified these associations. Methods: The Pathways Heart Study is a prospective cohort study examining incident CVD outcomes and risk factors in women with BC at Kaiser Permanente Northern California (KPNC). Eligible women were diagnosed with stage I-IV invasive BC from 2005-2013, &ge;21 years old, and KPNC members &ge;12 months at diagnosis. KPNC records provided demographic and BC therapy characteristics. Incident CVD outcomes [ischemic heart disease, heart failure/cardiomyopathy (HF/CM), stroke] were assessed from ICD9/10 codes. Multivariable Cox models estimated hazard ratios (HR) and 95% confidence intervals (CI) of each CVD outcome by cancer therapy received compared to not receiving that therapy, excluding those with prevalent CVD. Separate regression models included interaction terms for cancer therapy by overweight, obesity, diabetes, dyslipidemia, and hypertension to test whether the CVD outcome risk varied by presence of these factors at diagnosis. Results: Among 4,181 BC survivors with mean age of 59.6±12.0 years and mean follow-up of 7.9±3.5 years (range: 0.04-13.3), cancer therapies were not associated with incident CVD. However, CVD risks varied by BMI and prevalence of CVD risk factors at BC diagnosis. Normal weight (NW) women who received anthracyclines had higher risk of ischemic heart disease and HF/CM relative to NW women not receiving these therapies; interaction terms indicated HF/CM risk was statistically different than risks for obese women (Table). NW women who received cyclophosphamide or left-sided radiation had higher risk of HF/CM and stroke relative to NW women not receiving these therapies; these risks were statistically different from obese (for cyclophosphamide) or overweight (for radiation) women. Relative to women not receiving these therapies, higher HRs for HF/CM were observed among non-diabetic women who received cyclophosphamide (2.03, CI: 1.22-3.37), non-dyslipidemic women who received anthracyclines (3.65, CI: 1.69-7.87), and non-hypertensive women who received either anthracyclines (4.04, CI: 1.81-9.03) or cyclophosphamide (2.66, CI: 1.23-5.74) (P for interaction range: 0.04 to 0.06). Conclusion: Certain chemotherapy drugs may increase the risk of CVD in NW BC survivors; overweight and obese BC survivors may experience less risk than NW women. While chemotherapy also appears to increase HF/CM risk for women without diabetes, dyslipidemia, and hypertension, these conditions are more prevalent among overweight/obese women. Analysis within these subgroups is needed and forthcoming.

Table. Adjusted HRs (95% CI) of CVD outcomes among breast cancer survivors receiving select cancer therapies* stratified by BMI status at diagnosisBMI Ischemic heart diseaseHeart failure/CardiomyopathyStrokeAnthracycline, n=1283Normal4.22 (1.59, 11.2)5.27 (2.54, 10.9)1.89 (0.79, 4.53)Overweight1.66 (0.73, 3.77)2.17 (1.15, 4.11)0.40 (0.16, 0.99)Obese1.26 (0.56, 2.85)1.1 (0.54, 2.27)a0.33 (0.13, 0.83)aCyclophosphamide, n=1705Normal1.63 (0.61, 4.31)3.28 (1.59, 6.75)2.21 (1.01, 4.84)Overweight1.59 (0.75, 3.39)1.63 (0.9, 2.97)0.73 (0.34, 1.58)Obese0.85 (0.39, 1.86)0.75 (0.38, 1.47)a0.31 (0.13, 0.71)aLeft-Side Radiation, n=1331Normal1.44 (0.56, 3.69)2.04 (1.0, 4.18)2.38 (1.28, 4.42)Overweight1.47 (0.68, 3.16)0.68 (0.34, 1.34)b0.72 (0.37, 1.4)bObese1.32 (0.73, 2.38)1.30 (0.79, 2.16)1.05 (0.61, 1.82)*Cancer therapies with non-significant findings (i.e., Trastuzumab, taxanes, aromatase inhibitors, Tamoxifen, and any-side radiation) are not shown.ap≤0.05 normal weight v. obese; bp≤0.05 normal weight v. overweight

Citation Format: Heather Greenlee, Eileen Rillamas-Sun, Carlos Iribarren, Richard Cheng, Romain Neugebauer, Jamal S. Rana, Mai Nguyen-Huynh, Zaixing Shi, Cecile A. Laurent, Valerie S. Lee, Janise M. Roh, Hanjie Shen, Dawn L. Hershman, Lawrence H. Kushi, Marilyn L. Kwan. Cardiovascular disease risk of breast cancer therapies: The pathways heart study [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD5-01.

Risk of Cardiometabolic Risk Factors in Women With and Without a History of Breast Cancer: The Pathways Heart Study

PURPOSE

The incidence of cardiometabolic risk factors in breast cancer (BC) survivors has not been well described. Thus, we compared risk of hypertension, diabetes, and dyslipidemia in women with and without BC.

METHODS

Women with invasive BC diagnosed from 2005 to 2013 at Kaiser Permanente Northern California (KPNC) were identified and matched 1:5 to noncancer controls on birth year, race, and ethnicity. Cumulative incidence rates of hypertension, diabetes, and dyslipidemia were estimated with competing risk of overall death. Subdistribution hazard ratios (sHRs) were estimated by Fine and Gray regression, adjusted for cardiovascular disease-related risk factors, and stratified by treatment and body mass index (BMI).

RESULTS

A total of 14,942 BC cases and 74,702 matched controls were identified with mean age 61.2 years and 65% non-Hispanic White. Compared with controls, BC cases had higher cumulative incidence rates of hypertension (10.9% v 8.9%) and diabetes (2.1% v 1.7%) after 2 years, with higher diabetes incidence persisting after 10 years (9.3% v 8.8%). In multivariable models, cases had higher risk of diabetes (sHR, 1.16; 95% CI, 1.07 to 1.26) versus controls. Cases treated with chemotherapy (sHR, 1.23; 95% CI, 1.11 to 1.38), left-sided radiation (sHR, 1.29; 95% CI, 1.13 to 1.48), or endocrine therapy (sHR, 1.23; 95% CI, 1.12 to 1.34) continued to have higher diabetes risk. Hypertension risk was higher for cases receiving left-sided radiation (sHR, 1.11; 95% CI, 1.02 to 1.21) or endocrine therapy (sHR, 1.10; 95% CI, 1.03 to 1.16). Normal-weight (BMI < 24.9 kg/m²) cases had higher risks overall and within treatment subgroups versus controls.

CONCLUSION

BC survivors at KPNC experienced elevated risks of diabetes and hypertension compared with women without BC depending on treatments received and BMI. Future studies should examine strategies for cardiometabolic risk factor prevention in BC survivors.

Modeling risks of cardiovascular and cancer mortality following a diagnosis of loco-regional breast cancer

Background

Many women with breast cancer also have a high likelihood of cardiovascular mortality, and while there are several cardiovascular risk prediction models, none have been validated in a cohort of breast cancer patients. We first compared the performance of commonly-used cardiovascular models, and then derived a new model where breast cancer and cardiovascular mortality were modeled simultaneously, to account for the competing risk endpoints and commonality of risk factors between the two events.

Methods

We included 20,462 women diagnosed with stage I–III breast cancer between 2000 and 2010 in Kaiser Permanente Northern California (KPNC) with follow-up through April 30, 2015, and examined the performance of the Framingham, CORE and SCOREOP cardiovascular risk models by area under the receiver operating characteristic curve (AUC), and observed-to -expected (O/E) ratio. We developed a multi-state model based on cause-specific hazards (CSH) to jointly model the causes of mortality.

Results

The extended models including breast cancer characteristics (grade, tumor size, nodal involvement) with CVD risk factors had better discrimination at 5-years with AUCs of 0.85 (95% CI 0.83, 0.86) for cardiovascular death and 0.80 (95% CI 0.78, 0.87) for breast cancer death compared with the existing cardiovascular models evaluated at 5 years AUCs ranging 0.71–0.78. Five-year calibration for breast and cardiovascular mortality from our multi-state model was also excellent (O/E = 1.01, 95% CI 0.91–1.11).

Conclusion

A model incorporating cardiovascular risk factors, breast cancer characteristics, and competing events, outperformed traditional models of cardiovascular disease by simultaneously estimating cancer and cardiovascular mortality risks.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13058-021-01469-w.

Clinically sufficient vitamin D levels at breast cancer diagnosis and survival outcomes in a prospective cohort of 3,995 patients after a median follow-up of 10 years

10510

Background: There have been suggestive findings for better cancer survival with vitamin D supplementation in the recent VITAL trial. The findings are consistent with meta-analyses based on earlier randomized trials testing daily supplement vitamin D intake. As there is no ongoing or planned randomized trial of vitamin D supplementation in sight for women after breast cancer diagnosis, we evaluated relationships between serum levels of vitamin D and breast cancer outcomes in a large prospective cohort of breast cancer survivors. Methods: We measured 25-hydroxyvitamin D (25OHD) levels in serum samples collected at the time of diagnosis from 3,995 women with incident breast cancer enrolled in the Pathways Study, a large prospective cohort established in 2006 at Kaiser Permanente Northern California with active follow-up (FU). Potential determinants of 25OHD levels, including a polygenic score, were examined. Vitamin D levels were categorized based on clinical cutoffs as deficient ( < 20 ng/ml), insufficient (20 to < 30 ng/ml), or sufficient (≥30 ng/ml). These levels were then evaluated in relation to overall survival (OS), breast cancer-specific survival (BCSS), recurrence-free survival (RFS), and invasive disease-free survival (IDFS). Cox proportional hazards models were adjusted for non-clinical, clinical, and treatment factors and were further stratified by stage, estrogen receptor (ER) status, and body mass index (BMI). Results: Vitamin D supplement use, lower BMI, and self-reported white race were the strongest determinants of higher 25OHD levels. The polygenic score was significantly associated with 25OHD levels but explained only 0.3% of the variance. The median FU was 9.6 years (range: 0.3-13). Compared to those with deficient vitamin D levels, patients with sufficient levels had significantly better survival outcomes, which remained after controlling for various covariates (OS: HR [95% CI] = 0.73 [0.58-0.91]; BCSS: HR = 0.78 [0.56-1.09]; RFS: HR = 0.79 [0.65-0.97]; IDFS: HR = 0.82 [0.68-0.99]). Associations were similar by ER status, but stronger among patients with more advanced stage disease and those with under-weight or normal BMI. Black patients had the lowest 25OHD levels, which contributed to their poorer survival compared to white patients. Adding 25OHD levels to the Cox model of OS lowered the HR associated with Black vs. white race from 2.03 (1.57-2.62) to 1.79 (1.37-2.32). Conclusions: Sufficient vitamin D levels at the time of diagnosis were associated with improved breast cancer prognosis. Consistent with results from randomized trials, our findings from a large observational cohort of breast cancer survivors with long FU provide the strongest evidence to date for maintaining sufficient vitamin D levels in breast cancer patients, including among Black women and those with more advanced stage disease.

Diet Quality and Breast Cancer Recurrence and Survival: The Pathways Study

Background

Prior research suggests a relationship between overall diet quality and breast cancer survival, although few studies have reported on this topic. We evaluated whether 4 dietary quality indices consistent with healthy eating recommendations around the time of breast cancer diagnosis were associated with risk of recurrence, cause-specific, and all-cause mortality.

Methods

A total of 3660 women diagnosed with invasive breast cancer were included. Diet was assessed an average of 2.3 (range = 0.7-18.7) months after diagnosis, from which 4 dietary quality indices were derived: the American Cancer Society guidelines (ACS), the alternate Mediterranean Diet Index (aMED), the Dietary Approaches to Stop Hypertension (DASH), and the 2015 Healthy Eating Index (HEI). Over 40 888 person-years of follow-up, 461 breast cancer recurrences, and 655 deaths were ascertained. Cox models were used to estimate hazards ratios (HRs) and 95% confidence intervals (CIs).

Results

Adjusted comparisons between extreme quintiles showed all 4 dietary quality indices to be inversely associated with all-cause mortality, suggesting a 21%-27% lower risk (ACS HR = 0.73, 95% CI = 0.56 to 0.95; aMED HR = 0.79, 95% CI = 0.61 to 1.03; DASH HR = 0.76, 95% CI = 0.58 to 1.00; HEI HR = 0.77, 95% CI = 0.60 to 1.01). Similar patterns were noted for non-breast cancer mortality (ACS HR = 0.69, 95% CI = 0.48 to 0.98; aMED HR = 0.73, 95% CI = 0.50 to 1.05; DASH HR = 0.55, 95% CI = 0.38 to 0.79; HEI HR = 0.67, 95% CI = 0.48 to 0.94). None of the dietary quality indices were associated with recurrence or breast cancer-specific mortality.

Conclusion

Food intake patterns concordant with dietary quality indices consistent with recommendations for healthy eating may be beneficial for women with breast cancer.

Abstract GS2-05: Genome-wide association study identifies UACA as a modulator of breast cancer chemoresistance and survival

Prior studies suggest a strong genetic influence on breast cancer prognosis. Six genome-wide association studies (GWAS) on breast cancer prognosis have been published to date. However, none of the reported loci was replicated across studies and only two passed genome-wide significance (P &lt; 5 x 10-8). In the Pathways Study, a prospective cohort of breast cancer survivors begun in Kaiser Permanente Northern California (KPNC) in 2006, we carried out a GWAS of overall survival (OS) in 3,973 patients. Trans-ethnic meta-GWAS identified an association with OS of a locus on chromosome 15 that almost reached genome-wide significance (P = 9.42 x 10-8). This locus spanned the UACA gene, a key regulator of tumor suppressor Par-4. We found that receipt of chemotherapy modified the effect of the UACA locus on OS (Pinteraction = 2.4 x 10-4). This observation led us to hypothesize that the UACA locus effect on OS may be specific to Par-4 dependent chemotherapies, which include anti-HER2 therapy and doxorubicin. We stratified patients into two groups, those who received Par-4 dependent chemotherapy agents versus other patients. In separate trans-ethnic meta-GWAS, the UACA locus was significantly associated with OS in patients taking Par-4 dependent chemotherapies (P = 1.27 x 10-9), while no association was observed in the other patients (P = 0.21). To evaluate whether the UACA gene may be responsible for this association, we performed a transcriptome-wide association study (TWAS) of OS in White patients taking Par-4 dependent chemotherapies. Higher UACA gene expression was significantly associated with OS (P = 4.68 x 10-7), the only gene reaching transcriptome-wide significance (P &lt; 4.34 x 10-6). These results suggest that higher UACA expression may inhibit Par-4 induced apoptosis and lead to stronger chemoresistance and worse survival. We attempted to validate our findings in the independent KPNC Genetic Epidemiology Research on Aging (GERA) cohort. The GERA cohort included only 168 White patients with incident breast cancer after DNA collection who received Par-4 dependent chemotherapies. We found a non-significant association (hazard ratio (HR) = 1.46, P = 0.66) consistent with Pathways Study findings. However, the GERA cohort also included 1,983 prevalent breast cancer patients with biospecimen collection after diagnosis. In this group, the risk allele frequency in breast cancer survivors receiving Par-4 dependent chemotherapies was significantly lower than that in the White population (P = 5.50 x 10-3) while the risk allele frequency in the those not receiving these chemotherapies was similar to the population (P = 0.07). This is consistent with Pathways Study observations that the UACA locus risk allele significantly increased risk of mortality in patients taking Par-4 dependent chemotherapies. A higher mortality in breast cancer survivors carrying the risk allele would result in decreased risk allele frequency. We further validated our findings in Shanghai Breast Cancer Survival Study (SBCSS)and Shanghai Breast Cancer Study, which were conducted from 1996 to 2006 in urban Shanghai and recruited 5,575 breast cancer patients. In this independent Asian breast cancer population, the UACA locus was modestly associated with OS in the overall population (HR = 1.18, P = 0.012), and more significantly in 1,289 SBCSS patients who received anthracyclines (HR = 1.66, P = 1.55 x 10-4). This is the first human study suggesting the Par-4 pathway affects breast cancer patient survival with UACA a key modulator of treatment outcomes by anti-Her2 therapy and doxorubicin. Our findings suggest a path toward new predictive pharmacogenetic markers for personalized medicine targeting the Par-4 pathway for breast cancer treatment.

Citation Format: Lawrence H Kushi, Qianqian Zhu, Emily Schultz, Jirong Long, Janise M Roh, Emily Valice, Cecile A Laurent, Li Yan, Isaac J Ergas, Warren Davis, Dilrini K Ranatunga, Marilyn L Kwan, Ping-Ping Bao, Wei Zheng, Xiao-Ou Shu, Christine B Ambrosone, Song Yao. Genome-wide association study identifies UACA as a modulator of breast cancer chemoresistance and survival [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr GS2-05.

Effects of cooking methods on total isothiocyanate yield from cruciferous vegetables

Cruciferous vegetables are primary sources of dietary isothiocyanates (ITCs), a group of phytochemicals showing promising cancer-chemopreventive activities in multiple cancer models. However, no study has thoroughly examined how cooking affects the yields of ITCs from cruciferous vegetables. In this study, a high-performance liquid chromatography (HPLC)-based cyclocondensation assay was performed to examine the ITC yields from four major cruciferous vegetables (broccoli, cabbage, cauliflower, and kale) under six cooking conditions (stir-frying, steaming, microwaving, boiling, stewing, and chip-baking for kale only) and measured the level of ITCs under the raw condition for a comprehensive list of cruciferous vegetables and ITC-containing condiments. A wide range of ITC yields was found across vegetables and condiments. Cooking significantly altered the ITC yields, showing an averagely four-fold increase by lightly cooking (stir-frying, steaming, and microwaving) and a 58% decrease by heavily cooking (boiling, stewing, and chip-baking). These findings will provide the evidence-based cooking guidance on cruciferous vegetable consumption and help better estimate dietary ITC exposure in epidemiologic studies.

Distinct trajectories of moderate to vigorous physical activity and sedentary behavior following a breast cancer diagnosis: the Pathways Study

PURPOSE

To identify distinct trajectories of total moderate-to-vigorous physical activity (MVPA) and sedentary behavior following a breast cancer diagnosis and their correlates.

METHODS

The analysis examined 3000 female breast cancer survivors within Kaiser Permanente Northern California between 2006 and 2013. Self-reported time spent on total MVPA and sedentary behaviors were assessed at baseline (mean = 1.8 months post-diagnosis) and at 6 and 24 months follow up. Trajectory groups were identified using group-based trajectory modeling and K-means for longitudinal data analysis. Trajectory groups were named by baseline activity level (high, medium, or low) and direction of change (increaser, decreaser, or maintainer).

RESULTS

Trajectory analyses identified three MVPA trajectories [high decreaser (7%), medium decreaser (35%), low maintainer (58%)] and four sedentary behavior trajectories [high maintainer (18%), high decreaser (27%), low increaser (24%), and low maintainer (31%)]. Women with higher education (ORs: 1.63-4.37), income (OR: 1.37), dispositional optimism (ORs: 1.60-1.86), and social support (OR: 1.33) were more likely to be high or medium decreasers of MVPA (all P < 0.05). High maintainers and high decreasers of sedentary behavior were more likely to have higher education (OR: 1.84) and social support (ORs: 1.42-1.86), but lower income (OR: 0.66; all P < 0.05).

CONCLUSIONS

In the 24 months following breast cancer diagnosis, 42% of survivors decreased MVPA and 73% maintained or increased time on sedentary behavior. Socioeconomic status and stress coping at diagnosis predicted subsequent PA trajectory.

IMPLICATIONS FOR CANCER SURVIVORS

It is important to prioritize exercise intervention and counseling during early stage of breast cancer survivorship, especially in survivors who are at high risk of becoming physically inactive post-diagnosis.

Onset of cardiovascular disease risk factors in women with and without a history of breast cancer: The Pathways Heart Study

12017

Background: Women with a history of breast cancer (BC) are at increased long-term risk of dying from cardiovascular disease (CVD). However, the onset of CVD risk factors in women with BC has not been well-described. We compared risk of incident CVD risk factors in women with and without BC enrolled in the Kaiser Permanente Northern California (KPNC) integrated health system. Methods: Data were extracted from KPNC electronic health records. All invasive BC cases diagnosed between 2005-2013 were identified and matched 1:5 with controls on birth year, race/ethnicity and KPNC membership at the date of BC diagnosis. Cox regression models assessed the hazard of incident hypertension (based on diagnosis codes and filled prescriptions), dyslipidemia (based on diagnosis codes, filled prescriptions, and lab values), and diabetes (KPNC Diabetes Registry). Models were adjusted for baseline BMI, menopausal status, smoking status, neighborhood median household income, education, prevalent CVD conditions, and other baseline CVD risk factors. Subgroups of women who received chemotherapy, radiation therapy, and endocrine therapy were compared with controls. Results: A total of 14,942 women with a new diagnosis of invasive BC were identified and matched to 74,702 controls. On average, women were 62.0 years, 28.3 kg/m2BMI, 64.9% non-Hispanic white. Overall, cases were more likely to develop hypertension (HR: 1.18, 95% CI: 1.13, 1.24) and diabetes (HR: 1.23, 95% CI: 1.16, 1.31). Across the board, receipt of any of the three therapies (chemotherapy, radiation therapy and endocrine therapy) was associated with increased risk of hypertension and diabetes, compared to controls. Risk-factor specific hazard ratios for receipt of chemotherapy were (HR 1.18, 95% CI: 1.10, 1.27) and (HR 1.38, 95% CI: 1.26, 1.51), for hypertension and diabetes, respectively. For receipt of radiation therapy, risk-factor specific hazard ratios were (HR: 1.17, 95% CI: 1.09, 1.26) and (HR: 1.15, 95% CI: 1.04, 1.27), for hypertension and diabetes, respectively. Risk-factor specific hazard ratios for receipt of endocrine therapy were (HR: 1.22, 95% CI: 1.14, 1.30) and (HR: 1.16, 95% CI: 1.06, 1.27), for hypertension and diabetes, respectively. Conclusions: The risk of developing hypertension and diabetes is increased in women with BC who received chemotherapy, radiation therapy, and/or endocrine therapy. Future studies should examine the roles of CVD risk factor diagnosis and management on cardiometabolic risk in women with a BC history.

Risk of cardiovascular disease in women with and without a history of breast cancer: The Pathways Heart Study

12016

Background: Breast cancer (BC) survivors are at increased risk of cardiovascular disease (CVD) following diagnosis, as compared to women without BC. To provide a population-based estimate of CVD risk in BC survivors, we compared risk of CVD events in women with and without BC history enrolled in the Kaiser Permanente Northern California (KPNC) integrated health system. Methods: Data were extracted from KPNC electronic health records. All invasive BC cases diagnosed between 2005-2013 were identified and matched 1:5 with non-BC controls on birth year, race/ethnicity and KPNC membership at date of BC diagnosis. Cox regression models were used to assess differences in the hazard of four major CVD events (ischemic heart disease (IHD), heart failure (HF), cardiomyopathy, and stroke). Models were adjusted for factors known to influence risk of breast cancer or CVD.Other CVD events included arrhythmia, cardiac arrest, carotid disease, myocarditis/pericarditis, transient ischemic attack, valvular disease, and venous thromboembolism (VTE). We additionally examined subgroups of cases who received chemotherapy, radiation, and endocrine therapy, and their controls. Results: A total of 14,942 women with a new diagnosis of invasive BC were identified and matched to 74,702 women without BC history. On average, women were 62.0 years, 28.3 kg/m2BMI, 64.9% non-Hispanic white. Among all cases and controls, there were no significant differences in hazard of developing IHD, cardiomyopathy, and stroke; there was a borderline difference in HF (HR: 1.08, 95% CI: 0.99, 1.19). Cases were more likely to have a cardiac arrest (HR: 1.39, 95% CI: 1.09, 1.78) and develop VTE (HR: 1.97, 95% CI: 1.74, 2.23). Women treated with chemotherapy were more likely than controls to develop HF (HR: 1.44, 95% CI: 1.21, 1.72), cardiomyopathy (HR: 2.01, 95% CI: 1.02, 3.98), and VTE (HR: 3.15, 95% CI: 2.62, 3.79). Women who received radiation therapy were more likely to develop carotid disease (HR: 5.49, 95% CI: 1.22, 24.66) and VTE (HR: 1.65, 95% CI: 1.35, 2.03) than controls. Women who received endocrine therapy were more likely to experience a cardiac arrest (HR: 1.49, 95% CI: 1.07, 2.09) and develop VTE (HR: 1.70, 95% CI: 1.42, 2.03) than controls. Conclusions: Women with BC were at increased risk of heart failure, cardiomyopathy, cardiac arrest, VTE and carotid disease. These risks varied by cancer treatment, with higher risk in those who received chemotherapy. Future studies should explore the effects of chemotherapy class and radiation dose exposure on diverse CVD endpoints in BC survivors.

Serum bone markers and risk of osteoporosis and fragility fractures in women who received endocrine therapy for breast cancer: a prospective study

PURPOSE

Osteoporosis and fragility fracture are major bone toxicities of aromatase inhibitors (AIs) for postmenopausal hormone receptor-positive breast cancer. Except for a few small studies on bone turnover markers and reduced bone mineral density after AI treatment, data on the associations of bone markers and risk of osteoporosis or fracture from prospective studies are lacking.

METHODS

In a prospective study of 1709 women on AIs, two bone turnover markers, BALP and TRACP, and two bone regulatory markers, RANKL and OPG, were measured and examined in relation to risk of osteoporosis and fragility fractures during a median follow-up time of 6.1 years.

RESULTS

Higher levels of BALP and TRACP were both associated with increased risk of osteoporosis and higher BALP/TRACP ratios were associated with lower risk of osteoporosis, but no associations were observed for fracture risk. Higher levels of OPG were associated with increased risk of fracture, whereas higher levels of RANKL were associated with lower risk. As a result, OPG/RANKL ratios were positively associated with fracture risk [hazard ratio (HR) = 2.49, 95% confidence interval (CI) 1.34-4.61]. After controlling for age and fracture history, the associations became non-significant but a suggestive trend remained (HR = 1.80, 95% CI 0.96-3.37).

CONCLUSION

Our study provides suggestive evidence for the potential utility of OPG/RANKL ratios in predicting risk of fracture in women treated with AIs for breast cancer. Further validation may be warranted.

Distinct trajectories of fruits and vegetables, dietary fat, and alcohol intake following a breast cancer diagnosis: the Pathways Study

PURPOSE

To identify distinct diet trajectories after breast cancer (BC) diagnosis, and to examine the characteristics associated with diet trajectories.

METHODS

We analyzed 2865 Pathways Study participants who completed ≥ 2 food frequency questionnaires at the time of BC diagnosis (baseline), and at 6 and 24 months after baseline. Trajectory groups of fruit and vegetable (F/V) intake, % calories from dietary fat, and alcohol intake over 24 months were identified using group-based trajectory modeling. Associations between diet trajectories and sociodemographic, psychosocial, and clinical factors were analyzed using multinomial logistic regression.

RESULTS

Analyses identified 3 F/V trajectory groups, 4 dietary fat groups, and 3 alcohol groups. All 3 F/V trajectory groups reported slightly increased F/V intake post-diagnosis (mean increase = 0.2-0.5 serving/day), while 2 groups (48% of participants) persistently consumed < 4 servings/day of F/V. Dietary fat intake did not change post-diagnosis, with 45% of survivors maintaining a high-fat diet (> 40% of calories from fat). While most survivors consumed < 1 drink/day of alcohol at all times, 21% of survivors had 1.4-3.0 drinks/day at baseline and temporarily decreased to 0.1-0.5 drinks/day at 6 months. In multivariable analysis, diet trajectory groups were significantly associated with education (ORs: 1.93-2.49), income (ORs: 1.32-2.57), optimism (ORs: 1.93-2.49), social support (OR = 1.82), and changes in physical well-being (ORs: 0.58-0.61) and neuropathy symptoms after diagnosis (ORs: 1.29-1.66).

CONCLUSIONS

Pathways Study participants reported slightly increasing F/V and decreasing alcohol intake after BC diagnosis. Nearly half of survivors consumed insufficient F/V and excessive dietary fat. It is important to prioritize nutrition counseling and education in BC survivors.

Breast Cancer Chemoprevention in an Integrated Health Care Setting

PURPOSE

National guidelines encourage counseling high-risk women about pharmacologic breast cancer risk reduction. We evaluated the use of integrated health care data to identify and characterize breast cancer chemoprevention use. Chemoprevention included US Food and Drug Administration-approved use of tamoxifen and raloxifene and off-label use of aromatase inhibitors (AIs).

PATIENTS AND METHODS

Using electronic medical and pharmacy records (EMRs) in the Kaiser Permanente Northern California health care system, we sampled cancer-free women age 35 to 69 years who used tamoxifen, raloxifene, exemestane, anastrozole, or letrozole from 2005 to 2013. Risk-benefit profiles were calculated for tamoxifen and raloxifene using published indices. The proportion of days covered was calculated from pharmacy records to assess adherence.

RESULTS

Among 90 chemoprevention users (confirmed with EMR review from a sample of 371 women), 74% used tamoxifen, 11% used raloxifene, and 13% used an AI. For tamoxifen and raloxifene users, the risk-benefit index indicated 23% of women had insufficient evidence that benefits would outweigh risks. For all agents, adherence decreased from an average proportion of days covered of 75% at 1 year to 67% at 5 years. Automated EMR searches identified breast cancer chemoprevention users with 60% positive predictive value overall and 75% for tamoxifen after post hoc modifications.

CONCLUSION

Our study contributes to an emerging picture of breast cancer chemoprevention use in real-world settings, where evidence of net benefit is not uniform and nonadherence is common. Among breast cancer chemoprevention agents, our automated selection best performed for tamoxifen use. We also identified off-label use of AIs for chemoprevention, suggesting that expansion of risk-benefit indices to include AIs is warranted.

Early-onset triple-negative breast cancer in multiracial/ethnic populations: Distinct trends of prevalence of truncation mutations

Young black women are at higher risk of triple‐negative breast cancer (TNBC); however, a majority of the genetic studies on cancer predisposition were carried out in White populations. The underrepresentation of minority racial/ethnic populations in cancer genetic studies may have led to disproportionate gaps in our knowledge of cancer predisposition genes in these populations. We surveyed the protein‐truncating mutations at the exome‐wide scale and in known breast cancer predisposition genes among 170 patients of multiple racial/ethnic groups with early‐onset (≤age 50) TNBC from two independent cohorts. Black patients, on average, had a higher number of truncating mutations than Whites at the exome‐wide level, but fewer truncating mutations in the panel of known breast cancer genes. White TNBC patients showed a strong enrichment of truncating variants in known breast cancer genes, whereas no such enrichment was found among Black patients. Our findings indicate likely more breast cancer disposition genes yet to be discovered in minority racial/ethnic groups, and the current multigene panels may result in unequal benefits from cancer genetic testing.

Opportunities to Improve Detection and Treatment of Depression Among Patients With Breast Cancer Treated in an Integrated Delivery System

CONTEXT

Patients with cancer commonly experience depression. If not addressed, depression can lead to reduced quality of life and survival.

OBJECTIVE

Given the introduction of national initiatives to improve management of psychiatric symptoms among patients with cancer, we examined patterns of depression detection and treatment over time, and with respect to patient characteristics.

METHODS

This cross-sectional study linked data from the Pathways Study, a prospective cohort study of women diagnosed with breast cancer at Kaiser Permanente Northern California between 2005 and 2013, with data from Kaiser Permanente Northern California's electronic medical record. Pathways participants eligible for this analysis had no known prior depression but reported depressive symptoms at baseline. We used modified Poisson regression to assess the association of cancer diagnosis year and other patient characteristics with receipt of a documented clinician response to depressive symptoms (depression diagnosis, mental health referral, or antidepressant prescription).

RESULTS

Of the 725 women in our sample, 34% received a clinician response to depression. We observed no statistically significant association of breast cancer diagnosis year with clinician response. Characteristics associated with clinician response included Asian race (adjusted risk ratio, Asian vs. white: 0.44, 95% CI: 0.29-0.68) and depression severity (adjusted risk ratio, mild-moderate vs. severe depression: 1.45, 95% CI: 1.11-1.88).

CONCLUSION

Most patients in our sample did not receive a clinician response to their study-reported depression, and rates of response do not appear to have improved over time. Asian women, and those with less severe depression, appeared to be at increased risk of having unmet mental health care needs.

Perioperative Intravesical Chemotherapy for Patients WithNon-Muscle-invasive Bladder Cancer: Understanding the Extent of and Sources of Variation in Guideline-recommended Use

OBJECTIVE

To examine intravesical chemotherapy (IVC) use according to non-muscle-invasive bladder cancer patient disease risk, and the contributions of multilevel factors to variation in proficient use among patients with low-intermediate disease.

METHODS

This study included 988 patients diagnosed with non-muscle-invasive bladder cancer in an integrated health system in Northern California from 2015-2017. We calculated IVC receipt by disease risk, and among patients with low-intermediate risk disease, assessed the relationship between multilevel factors and IVC receipt using a logistic regression model with random intercepts for provider and service area, and patient-, provider-, and service area-level fixed effects. We further assessed the association of provider- and service area-level factors with IVC use by examining intraclass correlation coefficients.

RESULTS

Similar proportions of low-intermediate (36%) and high-risk (34%) patients received IVC. In the multivariate analysis, including low-intermediate risk patients, service area volume was strongly and statistically significantly associated with IVC use (adjusted odds ratio, high- vs low-volume: 0.08, 95% Confidence Interval: 0.01-0.58). Provider- and service area-level intraclass correlation coefficients were large, (38%, P = .0009 and 39% P = .03, respectively) indicating that much of the variance in IVC use was explained by factors at these levels.

CONCLUSION

Our findings highlight opportunities to improve proficient use of IVC. Future research should assess provider- and practice-level barriers to IVC use among low-intermediate risk patients.

Understanding racial/ethnic differences in breast cancer-related physical well-being: the role of patient-provider interactions

PURPOSE

Racial/ethnic differences in cancer symptom burden are well documented, but limited research has evaluated modifiable factors underlying these differences. Our objective was to examine the role of patient-provider interactions to help explain the relationship between race/ethnicity and cancer-specific physical well-being (PWB) among women with breast cancer.

METHODS

The Pathways Study is a prospective cohort study of 4505 women diagnosed with breast cancer at Kaiser Permanente Northern California between 2006 and 2013. Our analysis included white, black, Hispanic, and Asian participants who completed baseline assessments of PWB, measured using the Functional Assessment of Cancer Therapy for Breast Cancer, and patient-provider interactions, measured by the Interpersonal Processes of Care Survey (IPC) (N = 4002). Using step-wise linear regression, we examined associations of race/ethnicity with PWB, and changes in associations when IPC domains were added.

RESULTS

We observed racial/ethnic differences in PWB, with minorities reporting lower scores than whites (beta, black: - 1.79; beta, Hispanic: - 1.92; beta, Asian: - 1.68; p < 0.0001 for all comparisons). With the addition of health and demographic covariates to the model, associations between race/ethnicity and PWB score became attenuated for blacks and Asians (beta: - 0.63, p = 0.06; beta: - 0.68, p = 0.02, respectively) and, to a lesser extent, for Hispanic women (beta: - 1.06, p = 0.0003). Adjusting for IPC domains did not affect Hispanic-white differences (beta: - 1.08, p = 0.0002), and slightly attenuated black-white differences (beta: - 0.51, p = 0.14). Asian-white differences narrowed substantially (beta: - 0.31, p = 0.28).

CONCLUSIONS

IPC domains, including those capturing perceived discrimination, respect, and clarity of communication, appeared to partly explain PWB differences for black and Asian women. Results highlight opportunities to improve providers' interactions with minority patients, and communication with minority patients about their supportive care needs.

Abstract IA27: Disparities in breast cancer survivorship and outcomes

In the U.S., women of European ancestry have historically had the highest incidence of breast cancer compared to other major race/ethnicity groups. In recent years, the incidence rate for black women has approached that of white women, while rates for Asian and Hispanic women are about 25% lower than for white or black women. However, once diagnosed with breast cancer, black women have poorer survival rates than white women. The most recent “Annual Report to the Nation on the Status of Cancer” using nationwide cancer-registry data from 2006-2013 (Jemal et al., JNCI, 2017) reported a higher age- and stage-adjusted relative mortality risk after breast cancer of 1.71 (95% confidence interval (CI), 1.66-1.76) for non-Hispanic blacks compared to non-Hispanic whites. Hispanic women also experienced a slightly increased relative mortality risk of 1.14 (95% CI, 1.10-1.18) compared to white women, while Asians experienced a lower relative mortality risk of 0.84 (95% CI, 0.80-0.88).

The reasons for such disparities in outcomes after breast cancer are complex. One suggested contributing factor is differences in access to care, as blacks and Hispanics tend to be of lower socioeconomic status than whites or Asians. It is possible to minimize the effects of access to health care by examining outcomes after breast cancer diagnosis in an integrated health care setting such as Kaiser Permanente Northern California (KPNC), in which all patients have health insurance coverage with access to the same health care providers. We are currently conducting the Pathways Study, a prospective cohort study of 4,505 women diagnosed with breast cancer with enrollment from 2006-2013. This diverse cohort includes 557 Hispanics, 578 Asians, and 358 blacks.

Preliminary analyses in the larger population of 11,176 women who were diagnosed with invasive breast cancer in KPNC and eligible for the Pathways Study found that, despite the uniform health care access, racial disparities in mortality after breast cancer were qualitatively similar to those observed nationally. With 1,738 total deaths as of September 20, 2016, and adjusted for age and stage at diagnosis, compared to white women, black women had an increased relative mortality risk of 1.59 (95% CI, 1.24-2.03). For Hispanic women, the relative risk was 0.92 (95% CI, 0.72-1.19), and for Asians it was 0.70 (95% CI, 0.51-0.97). Among the subset of women enrolled in the Pathways Study (n=538 total deaths), comparable relative risks were 1.74 (95% CI, 1.35-2.24) for black women, 0.99 (95% CI, 0.75-1.29) for Hispanic women, and 0.73 (95% CI, 0.52-1.02) for Asians. Similar black-white differences were also seen for breast cancer-specific mortality and recurrence in the Pathways Study cohort in which recurrences are being documented.

These observations indicate that health care access is unlikely to explain racial/ethnic disparities in breast cancer outcomes. As the Pathways Study, we will be able to explore aspects of health care utilization, such as treatment-related factors such as treatment delay, adherence, and early discontinuation. We will also be able to explore presence of comorbid conditions or use of non-cancer medications that may influence mortality and breast cancer outcomes. In the Pathways Study, we are collecting data on lifestyle and psychosocial factors (e.g., food intake, physical activity, social support, doctor-patient communications, and quality of life); linking to geospatial databases to characterize the social and built environment of cohort members; and conducting genome-wide assays. For example, in preliminary analyses that adjusted additionally for estrogen receptor status, body mass index, educational attainment, and physical activity, black-white differences in mortality persisted even though they were somewhat attenuated (relative risk of 1.43; 95% CI, 1.09-1.86).

Along with other studies that are examining breast cancer outcomes in different populations, the Pathways Study is poised to contribute to better understanding of the persistent black-white differences in mortality after breast cancer, and thus identify avenues to improve outcomes for all women with breast cancer.

Citation Format: Lawrence H. Kushi, Isaac J. Ergas, Janise M. Roh, Scarlett Lin Gomez, Marilyn L. Kwan, Catherine Thomsen, Song Yao, Christine B. Ambrosone. Disparities in breast cancer survivorship and outcomes [abstract]. In: Proceedings of the Tenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2017 Sep 25-28; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2018;27(7 Suppl):Abstract nr IA27.

Genetic Ancestry Is not Associated with Breast Cancer Recurrence or Survival in U.S. Latina Women Enrolled in the Kaiser Permanente Pathways Study

Background: The U.S. Hispanic/Latino population is heterogeneous both socioculturally and by the proportion of European, Indigenous American, and African ancestry of the regions from which individuals originate. A previous study reported that genetic ancestry was associated with breast cancer survival among Latinas, independent of sociodemographic and tumor characteristics, suggesting that a genetic factor associated with ancestry may affect breast cancer survival.Methods: We evaluated the association of genetic ancestry with breast cancer outcomes among 506 Latina women with invasive breast cancer in the Pathways Study, a cohort study within Kaiser Permanente, an integrated health care delivery system. Proportional hazards models were used to assess the effect of ancestry on breast cancer recurrence (53 events), breast cancer-specific mortality (31 events) and all-cause mortality (54 events), with a mean follow-up time of 6 years.Results: Indigenous American ancestry was not associated with breast cancer recurrence [HR = 1.00 per 10% increase; 95% confidence interval (CI), 0.86-1.16], breast cancer mortality (HR = 0.95; 95% CI, 0.77-1.17), or all-cause mortality (HR = 0.93; 95% CI, 0.80-1.08). Adjustment for sociodemographic variables, tumor characteristics, and treatment did not alter the associations.Conclusions: Our results suggest that previously reported differences in breast cancer survival by genetic ancestry may be overcome by improving health care access and/or quality.Impact: Improving health care access and quality may reduce breast cancer disparities among U.S. Latinas. Cancer Epidemiol Biomarkers Prev; 26(9); 1466-9. ©2017 AACR.

Abstract P3-09-06: Predicting cardiovascular versus cancer mortality in a cohort of breast cancer survivors

Background: Given improved survival after breast cancer diagnosis for women with non-metastatic disease, many will likely survive their disease and ultimately die from causes other than breast cancer, the most frequent being cardiovascular disease. There are numerous risk prediction models, such as the Framingham risk score, to identify persons who are at high risk for a cardiovascular event or death. However, these models have been developed for use in the general population and have not been validated in any cohorts of cancer survivors, who are at increased risk for competing causes of death. We evaluated commonly used risk models for cardiovascular events on a contemporary cohort of breast cancer survivors, and developed a new risk model to simultaneously predict the likelihood of death from breast cancer or cardiovascular disease (CVD).

Methods: We included all women diagnosed with stage I-III breast cancer between January 1, 2000 and December 31, 2010 in Kaiser Permanente Northern California (KPNC) with follow-up through April 30, 2015. Specifically, we extracted from KPNC clinical and other databases: breast cancer characteristics, cardiovascular risk factors (cholesterol, blood pressure (BP), diabetes, BP lowering medication, smoking status), cardiovascular events, and cause of death. We assessed discrimination for the Framingham, CORE and SCOREOP cardiovascular risk models using the area under the receiver operating characteristic curve (AUC), and calibration by comparing the observed to the expected events. We used a multi-state model based on Cox cause specific hazards (CSH) to jointly model the risk of cardiovascular death and breast cancer death, while accounting for all other causes.

Results: In this population of 20,462 KPNC breast cancer survivors with a median follow-up of 7.5 years, there were 695 cardiovascular and 842 breast cancer deaths. The existing cardiovascular risk models discriminated adequately (AUCs ranging 0.64 – 0.78), though models predicting cardiovascular mortality tended to over-predict, while those predicting non-fatal events tended to under-predict. Models developed to predict in a shorter time frame (&lt;5 years), performed slightly better (E/O ratios of 1.08 and 1.18 for Framingham predicting events in the next 2 and 4 years, respectively). In our multi-state model, many of the traditional cardiovascular risk factors were no longer statistically significant (diabetes, BP) in predicting cardiovascular mortality, while the breast cancer characteristics (grade, tumor size, nodal involvement), as well as a prior history of CVD, were most useful in predicting cause of death. The model performed well, with AUCs of 0.85 (95% CI 0.83, 0.86) for 5-year risk of cardiovascular death and 0.85 (95% CI 0.84, 0.87) for breast cancer death.

Conclusion: If replicated in an independent cohort, our model suggests that breast cancer characteristics can help predict overall mortality as well as cardiovascular death. Given the risk of cardiovascular death in the population of breast cancer survivors, joint modeling of breast and cardiovascular mortality is warranted.

Citation Format: Leoce NM, Terry MB, Jin Z, Kushi LH, Roh JM, Laurent CA. Predicting cardiovascular versus cancer mortality in a cohort of breast cancer survivors [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-09-06.

Changes in bone mineral density in women with breast cancer receiving aromatase inhibitor therapy

PURPOSE

We assessed bone mineral density (BMD) change with aromatase inhibitor (AI) treatment in a contemporary cohort of women with breast cancer treated in Kaiser Permanente Northern California.

METHODS

Percent and estimated annual percent changes in BMD at the total hip and lumbar spine were examined in 676 women receiving AI therapy who had two serial BMD reports available (at least 1 year apart) before and after AI initiation (N = 317) or during continued AI therapy (N = 359). BMD changes were examined at the total hip and lumbar spine and compared by age and clinical subgroups.

RESULTS

Women experienced BMD declines after AI initiation or continued therapy, with median annual percent change - 1.2% (interquartile range, IQR - 2.4 to - 0.1%) at the hip and - 1.0% (IQR - 2.3 to 0.1%) at the spine after AI initiation, and - 1.1% (IQR - 2.4 to 0.1%) at the hip and - 0.9% (IQR - 2.4 to 0.5%) at the spine during continued therapy. Higher levels of bone loss were observed among younger (< 55 years) compared with older (≥ 75 years) women at the hip (- 1.6% vs. - 0.8%) and at the spine (- 1.5% vs. - 0.5%) after AI initiation, and at the hip (- 1.4% vs. - 1.2%) and at the spine (- 2.4% vs. - 0.001%) during continued therapy.

CONCLUSIONS

Small but consistent declines in total hip and lumbar spine BMD were present in breast cancer patients following AI therapy initiation or continued AI therapy. Although the overall rates of osteoporosis were low, greater estimated levels of annual bone loss were evident among women < 55 years.

Do differences in patient-provider relationships explain racial differences in side effect burden among women with breast cancer in the pathways study?

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Background: Prior research suggests that black patients with cancer report a greater burden of symptoms compared to white patients. Differences in patient-provider relationships may be an underlying and modifiable factor in these observed disparities. We examined differences in side effect burden by race/ethnicity and tested the hypothesis that patient-provider communication and trust may partly explain differences in symptom burden among women with breast cancer (BC). Methods: We conducted a cross-sectional analysis of data collected from 4,505 women diagnosed with BC from 2005-2013 at Kaiser Permanente Northern California. Women were asked two months post-diagnosis how much they were bothered by treatment side effects (FACT-B). Using modified Poisson regression, we assessed the association of race/ethnicity with side effect bother, adjusting for clinical characteristics, socioeconomic status (SES), and patient-provider communication and patients’ trust in providers in a step-wise fashion. Provider communication and trust were measured using the Interpersonal Processes of Care survey and a one-item assessment of patients’ trust in providers, respectively. Results: Before adjustment, Black, Hispanic, and Asian patients were at least 75% more likely than white patients to report high (vs. low) side effect bother (p < 0.0001). Bivariate associations of communication and trust with side effect bother and race/ethnicity were statistically significant. For example, patients with high (vs. low) scores for shared decision-making were more likely to be white than black (46% vs. 39%) and less likely to experience high vs. low side effect bother (10% vs. 14%, p < 0.0001 for both comparisons). However, after adjusting for clinical and SES characteristics in a multivariable analysis, the addition of patient-provider communication and trust to the model did not substantially alter disparity estimates. Conclusions: In our sample, patient-provider communication did not modify racial disparities in side effect bother. Further research is needed to explore additional modifiable factors underlying potential disparities in side effect management.

Patterns and reasons for switching classes of hormonal therapy among women with early-stage breast cancer

PURPOSE

Breast cancer patients can switch hormonal therapy (HT) regimens due to treatment side effects or menopausal status change. We describe HT class switching from aromatase inhibitor (AI) to tamoxifen (TAM), and vice versa.

METHODS

In a cohort of 3,265 women diagnosed with hormone-receptor-positive breast cancer at Kaiser Permanente Northern California from 2005 to 2013, we analyzed prescription records, switching reasons, and treatment adherence post-switch by chart review, through 31 December 2014.

RESULTS

There were 290 women who switched from AI to TAM (AI switchers), including 130 (45%) switchers during the first year of treatment; and 446 women who switched from TAM to AI (TAM switchers), including 120 (27%) switchers within the first year. After the switch, 136 (47%) AI switchers and 260 (58%) TAM switchers finished or remained on the planned therapy; 69 (24%) AI switchers and 99 (22%) TAM switchers discontinued therapy. AI side effects (73%), specifically joint pain/arthralgia and bone health issues, were the most common reasons for switching from AI to TAM, whereas from TAM to AI, it was menopausal status change (42%).

CONCLUSIONS

Study findings highlight the need for better ways to control patient symptoms from HT to prevent discontinuation, and thus ensure best prognosis.