Klassen, Christine L.

Abstract Background: Incorporation of Polygenic Risk Scores (PRS) can refine traditional breast cancer (BC) risk assessment models to provide precise estimates of BC risk. However, the impact of such an integrated model on BC risk estimates and clinical decision-making related to BC screening and preventive strategies in germline pathogenic variant (PV) carriers is not fully understood. Methods: The GENRE-2 is a prospective single-arm multisite clinical trial (NCT04474834) incorporating 313-PRS into standard BC risk assessment models to determine the impact of PRS on risk estimates and clinical decisions on prevention and screening. All women received pre- and post-PRS BC risk estimates and completed surveys on their screening and cancer prevention decisions before and after integrating PRS estimates. Herein, we report on the impact of integrating PRS into CanRisk-based BC risk estimates among women enrolled in GENRE-2 due to PVs in ATM, BRCA1, BRCA2, CHEK2, or PALB2. Women were categorized into average risk (<20%), moderate risk (20-40%), or high risk (>40%) for BC based on clinically relevant lifetime risk thresholds for supplemental MRI screening and risk-reducing bilateral mastectomies. Changes in categories of lifetime BC risk estimates were then evaluated before and after integration of PRS. Impact of PRS on patient decisions to undertake screening or preventive action (medication or prophylactic mastectomy) was evaluated based on pre- and post-PRS surveys. Results: Between 2020 and 2025, 933 women were enrolled, 633 received PRS results and completed a survey to date. Of those who received PRS results, 214 (33.8%) were PV carriers (ATM: 24, BRCA1: 54, BRCA2: 73, CHEK2: 54 and PALB2: 9). Among PV carriers, the CanRisk-based median 10-year and lifetime pre-PRS risk estimates were 6.0% and 23.9% for ATM, 22.5% and 77.5% for BRCA1, 17.9% and 77.6% for BRCA2, 7.1% and 26.6% for CHEK2, and 16.6% and 42.4% for PALB2, respectively. A total of 7 (29.2%) ATM PV carriers had a shift in lifetime BC risk categories after integration of PRS, with 1 (4.2%) shifting from average to moderate-risk, 3 (12.5%) shifting from moderate to average-risk category, and 3 (12.5%) shifting from moderate to high-risk category. Among CHEK2 PV carriers, 9 (16.7%) had a shift in lifetime risk categories, with 4 (7.4%) shifting from moderate to average-risk, 2 (3.7%) shifting from moderate to high-risk, and 3 (5.6%) shifting from high to moderate-risk. None of the BRCA1 and 4.1% of BRCA2 PV carriers had a shift in lifetime risk categories after PRS integration. Only 1 (11.1%) PALB2 PV carrier had a change in lifetime risk category after integration of PRS, although this was limited by a small sample. A significantly higher proportion of PV carriers with a high lifetime risk intended to take preventative action compared to the PV carriers with average lifetime risk (41.4% vs. 20.0%, p=0.007). Conclusions: Integration of PRS into BC lifetime risk estimates led to a clinically meaningful change in risk categories in 29.2% of ATM PV carriers and 16.7% of CHEK2 PV carriers, but in <5% of BRCA1 or BRCA2 PV carriers. These findings suggest that PRS may be helpful for BC risk stratification in moderate-risk genes such as ATM and CHEK2 but may have limited clinical utility in high-risk genes such as BRCA1 or BRCA2. Citation Format: S. Yadav, C. Klassen, D. Stan, J. Fraker, S. Sahni, S. A. Khan, L. Khatri, C. Vachon, D. Schaid, J. P. Sinnwell, E. Carlson, L. Hasadsri, F. J. Couch, S. Pruthi. Impact of Polygenic Risk Scores on Breast Cancer Risk Assessment and Clinical Decision Making in Carriers of Germline Pathogenic Variants in ATM, BRCA1, BRCA2, CHEK2, and PALB2: Results from the Prospective Multisite GENRE-2 Clinical Trial [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PD4-04.

10544 Background: Incorporation of Polygenic Risk Scores (PRS) can refine traditional breast cancer risk assessment models to provide precise estimates of breast cancer risk. However, the impact of such an integrated model on clinical decision-making related to breast cancer surveillance and preventive strategies is not fully understood. Methods: The GENRE-2 is a prospective single-arm multisite clinical trial (NCT04474834) incorporating PRS into standard breast cancer risk assessment models to determine the impact of PRS on clinical decisions on breast cancer prevention and surveillance. Women at high risk of breast cancer due to NCI-BCRAT 5-year risk of ≥ 3%, or IBIS (Tyrer-Cuzik) 10-year breast cancer risk of ≥5%, biopsy-proven high-risk breast lesion, or a pathogenic variant (PV) in ATM , BRCA1, BRCA2, CHEK2 or PALB2 , were enrolled from five sites in the United States. All women were invited to complete surveys on their breast surveillance and cancer prevention decisions based on pre-PRS standard risk models and post-PRS risk estimation, and further annual surveys are planned for 10 years. Results: Among 902 women enrolled in the study, 605 (median age: 52 years) received PRS results and completed a survey to date. Of those who received PRS results,195 (32.2%) were PV carriers. Among non-carriers, the median 10-year and lifetime pre-PRS IBIS-based risk was 10.0% and 28.7%, respectively. Among PV carriers, the CanRisk-based 10-year and lifetime pre-PRS risk estimates were 6.3% and 25.2% for ATM , 22.3% and 77.6% for BRCA1 , 18.5% and 77.7% for BRCA2 , 7.1% and 25.7% for CHEK2 , and 16.8% and 38.0% for PALB2 PV carriers, respectively. After the incorporation of PRS, the lifetime risk of breast cancer increased by at least 10% in 31% of non-carriers and 7.7% of PV carriers and decreased by at least 10% in 10.7% of non-carriers and 7.7% of PV carriers. The proportion of non-carriers with lifetime risk < 20% or > 40% changed from 17.3% and 22.0%, respectively, in the pre-PRS evaluation to 24.4% and 32.9%, in the post-PRS evaluation. A higher lifetime post-PRS score was associated with intent to take preventive action (surgery or endocrine agents). In non-carriers, the proportion of women with a lifetime risk < 20% with intent to take preventive action was 11%, compared to 36.8% of those with a lifetime risk > 40% (p < 0.001). Similarly, in PV carriers, the proportion of women with lifetime risk < 20% with intent to take preventive action was 20.8% compared to 41.1% of those with lifetime risk > 40% (p = 0.015). Conclusions: The GENRE-2 trial demonstrates that the incorporation of PRS into breast cancer risk assessment models in high-risk women is feasible and leads to clinically meaningful changes in breast cancer risk estimates and decision-making regarding preventive strategies. Evaluation of the implementation of breast cancer risk management strategies in study participants is ongoing and will be reported. Clinical trial information: NCT04474834 .

Abstract Purpose Many women are employed at the time of breast cancer (BC) diagnosis. Pre-diagnosis psychological distress is prevalent among early-stage BC patients. We prospectively evaluated return to work (RTW) in BC patients with and without reported pre-diagnosis psychological distress over a 15-month period to determine if such distress affects workforce participation and mental health status after curative treatment. Methods 188 patients with newly diagnosed stage 0-III BC and working 35-plus hours/week participated at Mayo Clinic in Minnesota and Florida. Patients received an email survey at diagnosis and 3 and 15 months later. Incidence of severe psychological distress (SPD) per the Kessler Psychological Distress Scale (K6, score ≥ 13) was assessed at each timepoint. Results 77/188 survey respondents (41%) reported pre-diagnosis psychological distress, with 23.5% noting job-related stress. 59/188 patients (31%) had SPD at diagnosis, with similar incidence in the group that had pre-diagnosis distress (+ stress) and the non-stressed group (no-stress). The sample was highly educated and well salaried. The + stress group worked more hours on average at diagnosis (41.3 vs. 39.3 hours, p = 0.034). At 3 months, 83/141 respondents (60.1%) reported taking time off work after diagnosis, with 46.6% returning within 2 weeks and 42.5% requiring > 4 weeks’ break. More + stress patients reported RTW to maintain health insurance (13/56 vs. 6/85, p = 0.006), although this difference resolved by 15 months. SPD rates decreased over time but affected 17/104 respondents (16.3%) at 15 months. Conclusion Job-related stress is a primary driver of pre-diagnosis psychological distress. Three months after BC diagnosis, many women with pre-diagnosis psychological distress were motivated to RTW to keep employer-linked health insurance. SPD is prominent in BC patients; while SPD declined over time, it did not resolve completely.

Abstract Women at increased risk for breast cancer may benefit from taking risk-reducing medication (RRM) with tamoxifen (tam). Historical uptake of tam in women who qualify has been low. Recent studies have shown low-dose tam to have similar efficacy to standard dosing, with lower risk for adverse events. In this study, we aimed to evaluate uptake, adherence, and tolerability of low-dose tam in women at increased risk for breast cancer and those with ductal carcinoma in situ (DCIS). In this two-site prospective study, women who qualified for breast cancer RRM were offered participation and received consultation with a breast specialist for discussion of RRM rationale, benefits, side effects, and risks. Patients received baseline and 1-year follow-up surveys. A total of 41 patients consented for participation, and 31 completed 1-year follow-up. After initial consultation, 90% (n = 37) reported good/complete understanding of breast cancer risk. Of patients included in 1-year follow-up, 5 had DCIS, 13 had high-risk intraepithelial lesion, and 13 qualified based on Breast Cancer Risk Assessment Tool/International Breast Intervention Study calculation. Furthermore, 74% (n = 23) of patients reported that they took low-dose tam after consultation, with 78.2% (n = 18) of those still taking medication at 1 year. Patients who continued medication had higher estimated breast cancer risk compared with those who discontinued (International Breast Intervention Study 10-year risk, 12.7% vs. 7.6%; P = 0.027). All patients with DCIS initiated low-dose tam, and only one patient with DCIS had discontinued at 1 year. Uptake of low-dose tam after informed discussion is high. Adherence and tolerability at 1-year follow-up improved compared with those with traditional dosing of tam. Prevention Relevance: tam has been used extensively for breast cancer prevention in high-risk women. Historical uptake has been low because of concern for side effects and poor tolerability. Herein, we demonstrate that in the clinical setting, effective patient education and offering of a low-dose option can improve uptake in this high-risk population. See related Spotlight, p. 545

Abstract INTRODUCTION Accelerated atherosclerosis has been described in breast cancer patients receiving cardiac exposure from adjuvant radiotherapy (RT). As a result of multidisciplinary care, breast cancer cure rates have improved in recent decades. Therefore, evaluating radiation-induced heart disease (RIHD), especially coronary artery disease (CAD), is essential. The 2022 cardio-oncology European Society of Cardiology (ESC) guidelines recommend screening patients 5 to 10 years after RT for CAD according to cardiovascular risk factors. This screening is generally recommended with exercise stress echocardiography since it can assess the physiological functional performance. Until now, it is unknown if dobutamine stress echocardiography (DSE) is an equal screening tool and if it can predict major adverse cardiovascular events (MACE) (myocardial infarction, stroke, cardiac death, revascularization). PURPOSE Evaluate if DSE is an adequate tool to stratify and predict MACE in post-radiotherapy patients. Methods A retrospective, descriptive cohort study was conducted. Patients who had chest RT for breast cancer and underwent DSE from 2000 to 2022 were included. A bivariate analysis, including Kruskal Wallis and Pearson Chi-Squared test, was done to identify variables associated with a positive DSE. A multivariable Cox Model for MACE and a time-to-event curve for MACE were also performed. Results We identified 163 patients that underwent DSE after a median time of 5.8 years from the end of RT. The median age was 74 years, 98.2% were female, 50% had left and 45% right breast cancer, 81% had hypertension, 41% diabetes mellitus, 71% dyslipidemia, 34% were smokers, and 19% had a prior myocardial infarction. The average dose of photon RT to the chest was 55Gy in the cohort, and 40% received chemotherapy before RT. Patients were divided into two groups: positive and negative DSE. A positive DSE was seen in 19.6%. The median (Q1, Q3) regional wall motion abnormalities (RWMA) of patients with a positive DSE was 1 (1, 1.015) at baseline and 1.280 (1.190, 1.520) at peak stress, and for a negative DSE, was 1 (1, 1) at baseline and peak stress. 88.2% of negative DSE and 87.5% of positive DSE achieved the target heart rate of 85%. HTN, dyslipidemia, and prior MI were significantly associated with a positive DSE (p &lt;0.023). The cumulative incidence of MACE was higher in the group of positive DSE (p&lt;0.001), even after adjusting for hypertension, diabetes mellitus, dyslipidemia, smoking, and prior myocardial infarction, with a hazard ratio of 2.500 (1.51 – 4.13) and a p&lt; 0.001. Similar results were observed regardless of RT laterality. Conclusions In breast cancer survivors that received adjuvant radiotherapy as part of multidisciplinary care, a positive DSE was an independent predictor of MACE compared to a negative result. These results support the usefulness of dobutamine stress echocardiography as a screening tool in breast cancer survivors.Kaplan-Meier Curve for MACE

Abstract Background Exercise stress echocardiography (ESE) is a non-invasive, radiation-free, and widely available technique that has demonstrated a reliable accuracy for the detection of coronary artery disease (CAD). Chest radiotherapy (RT) is associated with accelerated age-related atherosclerosis and fibrosis in a dose-dependent manner. ESE plays a role as a screening tool of RT induced heart disease, however, the prognostic value of changes in regional wall motion abnormalities in this population during ESE has not been evaluated. Methods This is a retrospective cohort study of breast cancer survivors treated with adjuvant RT that underwent ESE from 2000-2020 after treatment completion. Outcomes evaluated were: major adverse cardiovascular events (MACE: cardiovascular death, myocardial infarction, revascularization and stroke); and all-cause mortality. A univariate analysis was performed to characterize the population. Continuous variables were presented as means ± standard deviation (SD) or median with quartile 1 and 3 (Q1, Q3), and categorical variables as numbers and percentages. A Cox regression model adjusted by age and cardiovascular risk factors was used to evaluate variables associated with outcomes, and a time to first event approach was used. A p-value of &lt;0.05 was considered statistically significant. Results From 2000-2020, 507 patients, with a mean age 66 ± 10 years, underwent ESE at a median of 5.8 years after RT completion. The most prevalent comorbidities were dyslipidemia (59%), HTN (55%) and obesity (37%). 55% underwent RT for left-sided breast cancer and 45% for right-sided, and median RT dose was 6000 cGy. Baseline characteristics are presented in Table 1. Most patients underwent Bruce Protocol (92%). Patients exercised a mean time of 6.6 minutes achieving 7.3 METS and 109% of functional aerobic capacity (Table 2). At a median follow up of 7.8 years, 61 MACE events occurred. Predictors of MACE were double product, baseline and stress EF, baseline and peak regional wall motion abnormalities (RWMA), development of new ischemic RWMA, inability to reach 85% of maximum HR, and an abnormal EF response with stress after adjusting for age, HTN, DM, smoking history, dyslipidemia, obesity, prior MI and cancer staging (Fig 1). Predictors of all-cause mortality were METS, LV mass index, baseline and peak RWMA, development of new ischemic RWMA and an abnormal EF change with stress even after adjusting for variables described previously (Fig 2). Conclusions The development of new or worsening RWMA of just 2 segments with stress, was a significant predictor of MACE and all-cause mortality in a large cohort of breast cancer survivors undergoing multidisciplinary management including adjuvant RT. Special emphasis on management of cardiovascular comorbidities and closer surveillance are recommended for these patients.

Introduction: Exercise Stress Echocardiography (ESE) is recommended as a screening tool for the evaluation of Coronary Artery Disease (CAD) in patients with suspected Radiation-Induced Heart Disease (RIHD). Up to now, studies have only evaluated its association with the extent of CAD. Hypothesis Cancer survivors treated with chest Radiotherapy (RT) that undergo an ESE and have a +ESE develop more MACE than those who have -ESE. Methods: A retrospective, descriptive, cohort study was conducted. Patients who had chest RT and underwent ESE with Treadmill Bruce Stress Protocol, from 2000 to 2012, at Mayo Clinic Rochester and Mayo Clinic Health System were included. A univariate analysis was performed to characterize the population. An analysis including Kruskal Wallis and Pearson Chi-Squared tests was completed to identify variables associated with + SE (Table 1). Multivariable Cox Model for MACE was conducted and is shown in Table 2. A time-to-event curve using Kaplan-Meier estimates is shown in Figure 1. Results: We identified 113 patients, with a mean age of 67 years and a median follow-up of 15.1 years. Of those, 99% were female, 98% were breast cancer survivors, 59% had HTN, 14% DM, 11% AFib, 2% COPD, and 12% had a history of MI. All the patients received >3000cGy of Photon RT, and 57% were treated with systemic cancer therapies. A +ESE was seen in 20.3% of the patients with no significant difference in METS achieved compared with patients who had a -ESE. COPD, RT dose, and systemic therapies, specifically doxorubicin, were associated with a +ESE. The cumulative incidence of MACE was higher in the group of +ESE (p=0.029). After adjustment for HTN, DM, smoking history, hyperlipidemia, and prior MI, the HR for MACE associated with a +ESE was 1.97 (1.09-3.59). Conclusion: MACE was more frequent in patients with a +ESE who received chest RT and doxorubicin versus -ESE. These results support the usefulness of ESE in cancer survivors after RT as a cardiovascular screening tool.

e18883 Background: Women comprise more than 40% of the American workforce, with many women working at the time of a breast cancer diagnosis. Pre-diagnosis psychological distress is a rarely studied factor that may affect cancer survivors’ workforce participation and mental health status post treatment. In this 2-site prospective cohort study, we evaluated return to work (RTW) in breast cancer patients (pts) with and without reported pre-diagnosis stress. Methods: We enrolled 198 female pts at Mayo Clinic in Minnesota and Florida with newly diagnosed stage 0-III breast cancer who worked 35-plus hours/week at time of diagnosis. Pts were screened for eligibility at the intake visit. Eligible pts were emailed a baseline survey at the time of diagnosis, then a follow-up survey at 3 months. Surveys assessed demographics, work factors, treatment, and psychological distress per the validated Kessler Psychological Distress Scale (K6). Primary aims were to assess 1) the impact of pre-diagnosis psychological distress on RTW in pts with a breast cancer diagnosis and 2) the incidence of severe psychological distress (K6 ≥13) in those with and without delay in RTW. Wilcoxon rank sum tests were used to compare pts with and without pre-diagnosis stress at baseline and 3 months. Results: 189 and 142 pts took part in the baseline and 3-month surveys, respectively. Here, 40.7% of enrolled pts reported experiencing one or more major life stressors in the 18 months before diagnosis. At 3 months, 6 of the 75 pts who responded (8.0%) endorsed a delay in RTW after breast cancer diagnosis. Half of these pts (3/75) had reported a pre-diagnosis stressor, revealing no significant difference in time to RTW between the stressed and not-stressed groups. Median K6 at diagnosis in those with delay in RTW was 14 (range, 10-17), significantly higher than the median K6 of 9 in those without delay in RTW (range, 6-23; p = 0.026). 5/6 pts who reported delay in RTW had baseline or 3-month K6 ≥13. There was no significant difference in the number of pts with K6 ≥13 at baseline vs. 3 months (31.2% vs. 21.8%, p = 0.85). Overall, the pt population was well educated and well salaried. Conclusions: Pre-diagnosis psychological distress is prevalent, but it does not seem to be associated with delayed RTW in breast cancer pts; indeed, few pts reported a delay in RTW. Pts with delayed RTW after a breast cancer diagnosis had significantly higher median K6, generally ≥13. Thus, delay in RTW in breast cancer pts may be a surrogate marker of more serious psychological illness. Additional study in a socioeconomically diverse pt population is needed.

PURPOSE To determine the sensitivity and specificity of genetic testing criteria for the detection of germline pathogenic variants in women with breast cancer. MATERIALS AND METHODS Women with breast cancer enrolled in a breast cancer registry at a tertiary cancer center between 2000 and 2016 were evaluated for germline pathogenic variants in 9 breast cancer predisposition genes ( ATM , BRCA1, BRCA2, CDH1, CHEK2, NF1, PALB2, PTEN, and TP53). The performance of the National Comprehensive Cancer Network (NCCN) hereditary cancer testing criteria was evaluated relative to testing of all women as recommended by the American Society of Breast Surgeons. RESULTS Of 3,907 women, 1,872 (47.9%) meeting NCCN criteria were more likely to carry a pathogenic variant in 9 predisposition genes compared with women not meeting criteria (9.0% v 3.5%; P < .001). Of those not meeting criteria (n = 2,035), 14 (0.7%) had pathogenic variants in BRCA1 or BRCA2. The sensitivity of NCCN criteria was 70% for 9 predisposition genes and 87% for BRCA1 and BRCA2, with a specificity of 53%. Expansion of the NCCN criteria to include all women diagnosed with breast cancer at ≤ 65 years of age achieved > 90% sensitivity for the 9 predisposition genes and > 98% sensitivity for BRCA1 and BRCA2. CONCLUSION A substantial proportion of women with breast cancer carrying germline pathogenic variants in predisposition genes do not qualify for testing by NCCN criteria. Expansion of NCCN criteria to include all women diagnosed at ≤ 65 years of age improves the sensitivity of the selection criteria without requiring testing of all women with breast cancer.

Objective. To determine whether results of the nasopharyngeal FilmArray respiratory panel (NP-FARP) influenced antibiotic decisions. Methods. We reviewed the medical records of nonintensive care unit (ICU) inpatients that had an NP-FARP performed at our institution between June 2013 and June 2014. The inpatient records were reviewed 48 hours after the NP-FARP for the following data: demographic information; NP-FARP, serum procalcitonin, and methicillin-resistant Staphylococcus aureus nasal swab (MRSA NS) results; antibiotics prior and post-48 hours of the NP-FARP result; and the current immunosuppression status. Clinical outcome data were not obtained. Patients were categorized into those who had a positive (+) or a negative (−) NP-FARP. We further subdivided these two categories into groups A, B, and C based on the antibiotic modifications 48 hours after their NP-FARP result. Group A included patients who were never initiated on antimicrobial therapy. Patients whose antibiotics were discontinued or deescalated were placed in group B. Patients with antibiotic escalation or continuation without change constituted group C. We compared and analyzed groups A, B, and C in the (+) and (−) NP-FARP cohorts. Results. A total of 545 patients were included. There were 143 (26%) patients with positive and 402 (74%) patients with negative NP-FARPs. Comparison of groups A, B, and C between those with a (+) and (−) NP-FARP were as follows: (+) A and (−) A, 28/143 (20%) and 84/402 (21%); (+) B and (−) B, 59/143 (41%) and 147/402 (37%); and (+) C and (−) C, 56/143 (39%) and 171/402 (43%), respectively. We found no statistically significant differences between groups (+) A versus (−) A, (+) B versus (−) B, and (+) C versus (−) C with respect to age, gender, MRSA NS result, procalcitonin result, or concurrent immunosuppression. Conclusion. In non-ICU inpatients, NP-FARP alone or in combination with procalcitonin or MRSA NS did not influence antibiotic decisions during the study period.