Survival outcomes of patients with HER2/neu-positive breast cancer with germline BRCA mutations

BACKGROUND

Breast cancer (BC) with germline BRCA1/2 mutations and their association with triple-negative BC has been thoroughly investigated. However, some carriers of BRCA1/2 mutations have human epidermal growth factor receptor 2 (HER2/neu)-positive BC, which has a different targeted therapy approach, and data are scarce for this patient population. The authors sought to characterize the clinical characteristics and outcomes of patients with HER2/neu-positive BC who had germline BRCA1/2 mutations.

METHODS

This was a retrospective analysis of data from 1099 patients diagnosed with HER2/neu-positive BC who were screened for germline BRCA mutations between 1996 and 2022. Clinicopathologic features and survival rates were analyzed by BRCA mutation status. Univariate and multivariable Cox proportional hazards regression models were used to analyze the association between clinical variables and outcomes.

RESULTS

Of 1099 patients with HER2/neu-positive BC, 73 (6.6%) tested positive for BRCA1/2 mutations. Age, race, and tumor characteristics did not differ between BRCA noncarriers and carriers. At a median follow-up of 78.6 months, the 5-year recurrence-free survival rate was 85% in BRCA carriers and 87% in noncarriers (p = .79), and the 5-year overall survival rate was 94% in BRCA carriers and 94% in noncarriers (p = .78). In a multivariable model, BRCA was not associated with recurrence-free survival (hazard ratio, 0.99; 95% confidence interval, 0.51-1.90; p = .96) or overall survival (hazard ratio, 0.83; 95% confidence interval, 0.33-2.07; p = .69).

CONCLUSIONS

BRCA1/2 mutations occurred in 6.6% of patients with HER2/neu-positive BC and did not affect survival outcomes. Assessing the potential benefits of new treatment strategies, such as combining anti-HER2/neu therapies with poly(ADP-ribose) polymerase inhibitors, may lead to enhanced outcomes for these patients.

Validating Risk Prediction Models for Multiple Primaries and Competing Cancer Outcomes in Families With Li-Fraumeni Syndrome Using Clinically Ascertained Data

PURPOSE

There exists a barrier between developing and disseminating risk prediction models in clinical settings. We hypothesize that this barrier may be lifted by demonstrating the utility of these models using incomplete data that are collected in real clinical sessions, as compared with the commonly used research cohorts that are meticulously collected.

MATERIALS AND METHODS

Genetic counselors (GCs) collect family history when patients (ie, probands) come to MD Anderson Cancer Center for risk assessment of Li-Fraumeni syndrome, a genetic disorder characterized by deleterious germline mutations in the TP53 gene. Our clinical counseling-based (CCB) cohort consists of 3,297 individuals across 124 families (522 cases of single primary cancer and 125 cases of multiple primary cancers). We applied our software suite LFSPRO to make risk predictions and assessed performance in discrimination using AUC and in calibration using observed/expected (O/E) ratio.

RESULTS

For prediction of deleterious TP53 mutations, we achieved an AUC of 0.78 (95% CI, 0.71 to 0.85) and an O/E ratio of 1.66 (95% CI, 1.53 to 1.80). Using the LFSPRO.MPC model to predict the onset of the second cancer, we obtained an AUC of 0.70 (95% CI, 0.58 to 0.82). Using the LFSPRO.CS model to predict the onset of different cancer types as the first primary, we achieved AUCs between 0.70 and 0.83 for sarcoma, breast cancer, or other cancers combined.

CONCLUSION

We describe a study that fills in the critical gap in knowledge for the utility of risk prediction models. Using a CCB cohort, our previously validated models have demonstrated good performance and outperformed the standard clinical criteria. Our study suggests that better risk counseling may be achieved by GCs using these already-developed mathematical models.

Large-scale genome-wide association study of 398,238 women unveils seven novel loci associated with high-grade serous epithelial ovarian cancer risk

Background

Nineteen genomic regions have been associated with high-grade serous ovarian cancer (HGSOC). We used data from the Ovarian Cancer Association Consortium (OCAC), Consortium of Investigators of Modifiers of BRCA1/BRCA2 (CIMBA), UK Biobank (UKBB), and FinnGen to identify novel HGSOC susceptibility loci and develop polygenic scores (PGS).

Methods

We analyzed >22 million variants for 398,238 women. Associations were assessed separately by consortium and meta-analysed. OCAC and CIMBA data were used to develop PGS which were trained on FinnGen data and validated in UKBB and BioBank Japan.

Results

Eight novel variants were associated with HGSOC risk. An interesting discovery biologically was finding that TP53 3'-UTR SNP rs78378222 was associated with HGSOC (per T allele relative risk (RR)=1.44, 95%CI:1.28-1.62, P=1.76×10-9). The optimal PGS included 64,518 variants and was associated with an odds ratio of 1.46 (95%CI:1.37-1.54) per standard deviation in the UKBB validation (AUROC curve=0.61, 95%CI:0.59-0.62).

Conclusions

This study represents the largest GWAS for HGSOC to date. The results highlight that improvements in imputation reference panels and increased sample sizes can identify HGSOC associated variants that previously went undetected, resulting in improved PGS. The use of updated PGS in cancer risk prediction algorithms will then improve personalized risk prediction for HGSOC.

Veliparib with carboplatin and paclitaxel in BRCA-mutated advanced breast cancer (BROCADE3): Final overall survival results from a randomized phase 3 trial

BACKGROUND

In the BROCADE3 study, the addition of veliparib to carboplatin plus paclitaxel resulted in a significant improvement in progression-free survival (PFS) compared with placebo plus carboplatin and paclitaxel, in patients with germline BRCA1 or BRCA2 (BRCA1/2)-mutated, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. We now report final overall survival (OS) data.

METHODS

BROCADE3 is a randomized phase 3 study that enrolled patients with BRCA1/2-mutated, HER2-negative advanced breast cancer who received ≤ 2 prior lines of chemotherapy for metastatic disease. Patients were randomized 2:1 to carboplatin and paclitaxel, dosed with either veliparib or matching placebo. OS was a secondary endpoint.

RESULTS

In the intention-to-treat population (N = 509), 337 patients were randomized to receive veliparib and 172 to placebo. Median OS was 32.4 months vs 28.2 months (hazard ratio, 0.916; 95% CI, 0.736-1.140; P = .434). The updated safety data for veliparib are consistent with those reported in the primary analysis; the addition of veliparib was generally well tolerated.

CONCLUSIONS

Final OS data indicate that the PFS improvement shown in the primary analysis did not translate into an OS benefit. The long survival times observed in both arms suggest that combination therapy with paclitaxel and carboplatin provides clinical benefit in the population of patients with BRCA1/2-mutated metastatic breast cancer.

LFSPROShiny: An Interactive R/Shiny App for Prediction and Visualization of Cancer Risks in Families With Deleterious Germline TP53 Mutations

PURPOSE

LFSPRO is an R library that implements risk prediction models for Li-Fraumeni syndrome (LFS), a genetic disorder characterized by deleterious germline mutations in the TP53 gene. To facilitate the use of these models in clinics, we developed LFSPROShiny, an interactive R/Shiny interface of LFSPRO that allows genetic counselors (GCs) to perform risk predictions without any programming components and further visualize the risk profiles of their patients to aid the decision-making process.

METHODS

LFSPROShiny implements two models that have been validated on multiple LFS patient cohorts: a competing risk model that predicts cancer-specific risks for the first primary and a recurrent-event model that predicts the risk of a second primary tumor. Starting with a visualization template, we keep regular contact with GCs, who ran LFSPROShiny in their counseling sessions, to collect feedback and discuss potential improvement. On receiving the family history as input, LFSPROShiny renders the family into a pedigree and displays the risk estimates of the family members in a tabular format. The software offers interactive overlaid side-by-side bar charts for visualization of the patients' cancer risks relative to the general population.

RESULTS

We walk through a detailed example to illustrate how GCs can run LFSPROShiny in clinics from data preparation to downstream analyses and interpretation of results with an emphasis on the utilities that LFSPROShiny provides to aid decision making.

CONCLUSION

Since December 2021, we have applied LFSPROShiny to over 100 families from counseling sessions at the MD Anderson Cancer Center. Our study suggests that software tools with easy-to-use interfaces are crucial for the dissemination of risk prediction models in clinical settings, hence serving as a guideline for future development of similar models.

Systemic Treatment of Patients With Metastatic Breast Cancer: ASCO Resource-Stratified Guideline Q and A

The Systemic Treatment of Patients with Metastatic Breast Cancer: @ASCO Resource-Stratified Guideline Q and A presents takeways, rationale, and key recommendations based on #JCOGO full guideline for patients by menopausal and marker status.

Systemic Treatment of Patients With Metastatic Breast Cancer: ASCO Resource-Stratified Guideline

PURPOSE

To guide clinicians and policymakers in three global resource-constrained settings on treating patients with metastatic breast cancer (MBC) when Maximal setting-guideline recommended treatment is unavailable.

METHODS

A multidisciplinary, multinational panel reviewed existing ASCO guidelines and conducted modified ADAPTE and formal consensus processes.

RESULTS

Four published resource-agnostic guidelines were adapted for resource-constrained settings; informing two rounds of formal consensus; recommendations received ≥75% agreement.

RECOMMENDATIONS

Clinicians should recommend treatment according to menopausal status, pathological and biomarker features when quality results are available. In first-line, for hormone receptor (HR)-positive MBC, when a non-steroidal aromatase inhibitor and CDK 4/6 inhibitor combination is unavailable, use hormonal therapy alone. For life-threatening disease, use single-agent chemotherapy or surgery for local control. For premenopausal patients, use ovarian suppression or ablation plus hormone therapy in Basic settings. For human epidermal growth factor receptor 2 (HER2)-positive MBC, if trastuzumab, pertuzumab, and chemotherapy are unavailable, use trastuzumab and chemotherapy; if unavailable, use chemotherapy. For HER2-positive, HR-positive MBC, use standard first-line therapy, or endocrine therapy if contraindications. For triple-negative MBC with unknown PD-L1 status, or if PD-L1-positive and immunotherapy unavailable, use single-agent chemotherapy. For germline BRCA1/2 mutation-positive MBC, if poly(ADP-ribose) polymerase inhibitor is unavailable, use hormonal therapy (HR-positive MBC) and chemotherapy (HR-negative MBC). In second-line, for HR-positive MBC, Enhanced setting recommendations depend on prior treatment; for Limited, use tamoxifen or chemotherapy. For HER2-positive MBC, if trastuzumab deruxtecan is unavailable, use trastuzumab emtansine; if unavailable, capecitabine and lapatinib; if unavailable, trastuzumab and/or chemotherapy (hormonal therapy alone for HR-positive MBC).Additional information is available at www.asco.org/resource-stratified-guidelines. It is ASCO's view that healthcare providers and system decision-makers should be guided by the recommendations for the highest stratum of resources available. The guideline is intended to complement but not replace local guidelines.

Short-Term Biomarker Modulation Study of Dasatinib for Estrogen Receptor-Negative Breast Cancer Chemoprevention

Objective

Risk-reducing therapy with selective estrogen receptor (ER) modulators and aromatase inhibitors reduce breast cancer risk. However, the effects are limited to ER-positive breast cancer. Therefore, new agents with improved toxicity profiles that reduce the risk in ER-negative breast cancers are urgently needed. The aim of this prospective, short-term, prevention study was to evaluate the effect of dasatinib, an inhibitor of the tyrosine kinase Src, on biomarkers in normal (but increased risk) breast tissue and serum of women at high risk for a second, contralateral primary breast cancer.

Materials and Methods

Women with a history of unilateral stage I, II, or III ER-negative breast cancer, having no active disease, and who completed all adjuvant therapies were eligible. Patients underwent baseline fine-needle aspiration (FNA) of the contralateral breast and serum collection for biomarker analysis and were randomized to receive either no treatment (control) or dasatinib at 40 or 80 mg/day for three months. After three months, serum collection and breast FNA were repeated. Planned biomarker analysis consisted of changes in cytology and Ki-67 on breast FNA, and changes in serum levels of insulin-like growth factor 1 (IGF-1), IGF-binding protein 1, and IGF-binding protein 3. The primary objective was to evaluate changes in Ki-67 and secondary objective included changes in cytology in breast tissue and IGF-related serum biomarkers. Toxicity was also evaluated.

Results

Twenty-three patients started their assigned treatments. Compliance during the study was high, with 86.9% (20/23) of patients completing their assigned doses. Dasatinib was well tolerated and no drug-related grade 3 and 4 adverse events were observed. Since only one patient met the adequacy criteria for the paired FNA sample, we could not evaluate Ki-67 level or cytological changes. No significant change in serum biomarkers was observed among the three groups.

Conclusion

Dasatinib was well tolerated but did not induce any significant changes in serum biomarkers. The study could not fulfill its primary objective due to an inadequate number of paired FNA samples. Further, larger studies are needed to evaluate the effectiveness of Src inhibitors in breast cancer prevention.

Validating risk prediction models for multiple primaries and competing cancer outcomes in families with Li-Fraumeni syndrome using clinically ascertained data at a single institute

Purpose

There exists a barrier between developing and disseminating risk prediction models in clinical settings. We hypothesize this barrier may be lifted by demonstrating the utility of these models using incomplete data that are collected in real clinical sessions, as compared to the commonly used research cohorts that are meticulously collected.

Patients and methods

Genetic counselors (GCs) collect family history when patients (i.e., probands) come to MD Anderson Cancer Center for risk assessment of Li-Fraumeni syndrome, a genetic disorder characterized by deleterious germline mutations in the TP53 gene. Our clinical counseling-based (CCB) cohort consists of 3,297 individuals across 124 families (522 cases of single primary cancer and 125 cases of multiple primary cancers). We applied our software suite LFSPRO to make risk predictions and assessed performance in discrimination using area under the curve (AUC), and in calibration using observed/expected (O/E) ratio.

Results

For prediction of deleterious TP53 mutations, we achieved an AUC of 0.81 (95% CI, 0.70 - 0.91) and an O/E ratio of 0.96 (95% CI, 0.70 - 1.21). Using the LFSPRO.MPC model to predict the onset of the second cancer, we obtained an AUC of 0.70 (95% CI, 0.58 - 0.82). Using the LFSPRO.CS model to predict the onset of different cancer types as the first primary, we achieved AUCs between 0.70 and 0.83 for sarcoma, breast cancer, or other cancers combined.

Conclusion

We describe a study that fills in the critical gap in knowledge for the utility of risk prediction models. Using a CCB cohort, our previously validated models have demonstrated good performance and outperformed the standard clinical criteria. Our study suggests better risk counseling may be achieved by GCs using these already-developed mathematical models.

ENIGMA CHEK2gether Project: A Comprehensive Study Identifies Functionally Impaired CHEK2 Germline Missense Variants Associated with Increased Breast Cancer Risk

PURPOSE

Germline pathogenic variants in CHEK2 confer moderately elevated breast cancer risk (odds ratio, OR ∼ 2.5), qualifying carriers for enhanced breast cancer screening. Besides pathogenic variants, dozens of missense CHEK2 variants of uncertain significance (VUS) have been identified, hampering the clinical utility of germline genetic testing (GGT).

EXPERIMENTAL DESIGN

We collected 460 CHEK2 missense VUS identified by the ENIGMA consortium in 15 countries. Their functional characterization was performed using CHEK2-complementation assays quantifying KAP1 phosphorylation and CHK2 autophosphorylation in human RPE1-CHEK2-knockout cells. Concordant results in both functional assays were used to categorize CHEK2 VUS from 12 ENIGMA case-control datasets, including 73,048 female patients with breast cancer and 88,658 ethnicity-matched controls.

RESULTS

A total of 430/460 VUS were successfully analyzed, of which 340 (79.1%) were concordant in both functional assays and categorized as functionally impaired (N = 102), functionally intermediate (N = 12), or functionally wild-type (WT)-like (N = 226). We then examined their association with breast cancer risk in the case-control analysis. The OR and 95% CI (confidence intervals) for carriers of functionally impaired, intermediate, and WT-like variants were 2.83 (95% CI, 2.35-3.41), 1.57 (95% CI, 1.41-1.75), and 1.19 (95% CI, 1.08-1.31), respectively. The meta-analysis of population-specific datasets showed similar results.

CONCLUSIONS

We determined the functional consequences for the majority of CHEK2 missense VUS found in patients with breast cancer (3,660/4,436; 82.5%). Carriers of functionally impaired missense variants accounted for 0.5% of patients with breast cancer and were associated with a moderate risk similar to that of truncating CHEK2 variants. In contrast, 2.2% of all patients with breast cancer carried functionally wild-type/intermediate missense variants with no clinically relevant breast cancer risk in heterozygous carriers.

LFSPROShiny: an interactive R/Shiny app for prediction and visualization of cancer risks in families with deleterious germline TP53 mutations

Purpose

LFSPRO is an R library that implements risk prediction models for Li-Fraumeni syndrome (LFS), a genetic disorder characterized by deleterious germline mutations in the TP53 gene. To facilitate the use of these models in clinics, we developed LFSPROShiny, an interactive R/Shiny interface of LFSPRO that allows genetic counselors (GCs) to perform risk predictions without any programming components, and further visualize the risk profiles of their patients to aid the decision-making process.

Methods

LFSPROShiny implements two models that have been validated on multiple LFS patient cohorts: a competing-risk model that predicts cancer-specific risks for the first primary, and a recurrent-event model that predicts the risk of a second primary tumor. Starting with a visualization template, we keep regular contact with GCs, who ran LFSPROShiny in their counseling sessions, to collect feedback and discuss potential improvement. Upon receiving the family history as input, LFSPROShiny renders the family into a pedigree, and displays the risk estimates of the family members in a tabular format. The software offers interactive overlaid side-by-side bar charts for visualization of the patients' cancer risks relative to the general population.

Results

We walk through a detailed example to illustrate how GCs can run LFSPROShiny in clinics, from data preparation to downstream analyses and interpretation of results with an emphasis on the utilities that LFSPROShiny provides to aid decision making.

Conclusion

Since Dec 2021, we have applied LFSPROShiny to over 100 families from counseling sessions at MD Anderson Cancer Center. Our study suggests that software tools with easy-to-use interfaces are crucial for the dissemination of risk prediction models in clinical settings, hence serving as a guideline for future development of similar models.

PREDICT validity for prognosis of breast cancer patients with pathogenic BRCA1/2 variants

We assessed the PREDICT v 2.2 for prognosis of breast cancer patients with pathogenic germline BRCA1 and BRCA2 variants, using follow-up data from 5453 BRCA1/2 carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) and the Breast Cancer Association Consortium (BCAC). PREDICT for estrogen receptor (ER)-negative breast cancer had modest discrimination for BRCA1 carrier patients overall (Gönen & Heller unbiased concordance 0.65 in CIMBA, 0.64 in BCAC), but it distinguished clearly the high-mortality group from lower risk categories. In an analysis of low to high risk categories by PREDICT score percentiles, the observed mortality was consistently lower than the expected mortality, but the confidence intervals always included the calibration slope. Altogether, our results encourage the use of the PREDICT ER-negative model in management of breast cancer patients with germline BRCA1 variants. For the PREDICT ER-positive model, the discrimination was slightly lower in BRCA2 variant carriers (concordance 0.60 in CIMBA, 0.65 in BCAC). Especially, inclusion of the tumor grade distorted the prognostic estimates. The breast cancer mortality of BRCA2 carriers was underestimated at the low end of the PREDICT score distribution, whereas at the high end, the mortality was overestimated. These data suggest that BRCA2 status should also be taken into consideration with tumor characteristics, when estimating the prognosis of ER-positive breast cancer patients.

Outcomes of the "BRCA Quality Improvement Dissemination Program": An initiative to improve patient receipt of cancer genetics services at five health systems

OBJECTIVE

A quality improvement initiative (QII) was conducted with five community-based health systems' oncology care centers (sites A-E). The QII aimed to increase referrals, genetic counseling (GC), and germline genetic testing (GT) for patients with ovarian cancer (OC) and triple-negative breast cancer (TNBC).

METHODS

QII activities occurred at sites over several years, all concluding by December 2020. Medical records of patients with OC and TNBC were reviewed, and rates of referral, GC, and GT of patients diagnosed during the 2 years before the QII were compared to those diagnosed during the QII. Outcomes were analyzed using descriptive statistics, two-sample t-test, chi-squared/Fisher's exact test, and logistic regression.

RESULTS

For patients with OC, improvement was observed in the rate of referral (from 70% to 79%), GC (from 44% to 61%), GT (from 54% to 62%) and decreased time from diagnosis to GC and GT. For patients with TNBC, increased rates of referral (from 90% to 92%), GC (from 68% to 72%) and GT (81% to 86%) were observed. Effective interventions streamlined GC scheduling and standardized referral processes.

CONCLUSION

A multi-year QII increased patient referral and uptake of recommended genetics services across five unique community-based oncology care settings.

Abstract P1-05-26: A blood-based lipid panel for personalized risk assessment of breast cancer

Background: The metabolic syndrome characterized in part by obesity, hyperinsulinemia, and insulin resistance is associated with increased risk of breast cancer. However there remains a need to establish a circulating biomarker metabolic profile indicative of increased risk of breast cancer. In the current study, we performed a comprehensive metabolomics screen to identify biomarkers indicative of increased risk of breast cancer. Methods: Unbiased metabolomics profiling was conducted on an initial Development Set of plasmas collected from 353 newly-diagnosed breast cancer cases and 141 controls. A deep learning neural network with 3 layers each containing 32 nodes based on 11 individual lipids corresponding to discrete lipid subclasses was built for risk prediction of breast cancer. The model was validated in an independent Test Set consisting of 79 breast cancer cases and 163 controls. Using a nested case:control matched design, we evaluated the performance of the model among body mass index (BMI) strata (≥ 30 or < 30kg/m2). Results: An 11-marker lipid biomarker panel encompassing lipid subclasses with known pro-inflammatory and tumor promoting roles yielded an AUC of 0.75 (95% CI: 0.70-0.79) for distinguishing breast cancer cases from controls in the Development Set. Predictive performance of the lipid panel was comparable when stratifying cases into hormone-receptor (HR) positive, HER2-positive/HR negative, and triple-negative breast cancer subtypes. The biomarker panel had an AUC of 0.74 (95% CI: 0.68-0.81) in the independent Test Set. The predictive performance of the panel was most pronounced among obese subjects (BMI ≥ 30) with an AUC of 0.81 (95% CI: 0.71-0.91) in the Test Set. Conclusions: The lipid-based biomarker panel has utility for identifying women with ‘metabolic obesity’ who are at increased risk of breast cancer and would benefit from tailored screening.

Citation Format: Johannes Fahrmann, Ehsan Irajizad, Jody Vykoukal, Angelica Gutierrez Barrera, Jennifer Dennison, Ranran Wu, Banu K. Arun, Abenaa Brewster, Samir Hanash. A blood-based lipid panel for personalized risk assessment of 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 P1-05-26.

Abstract OT2-13-01: Willingness to Participate in a Trial Comparing Standard Genetic Counseling versus Genetic Counseling with Personalized Cancer Risks Estimates in Patients with Li-Fraumeni Syndrome

Background: Individuals with Li-Fraumeni Syndrome (LFS) have increased risk of developing breast cancer, sarcomas, brain tumors, leukemia, and other cancers throughout their lifetime. LFS is primarily caused by autosomal dominant germline mutations in the TP53 tumor suppressor gene. Due to the large number of cancers caused by LFS, and their variable age of presentation, each LFS family often presents very differently. Currently, standard genetic counseling for patients with LFS often involves general lifetime risk predictions for developing several primary cancers. At present, there are no standard tools available to help genetics providers obtain a personalized risk assessment for a patient with LFS based on their unique personal and family history data. To address this, the LFSPRO risk model was developed to estimate the likelihood of a proband having LFS, to provide cancer-specific risks of a first primary cancer, and to estimate risk of time to second primary cancer diagnosis by utilizing detailed personal and family history information. Specific Aims: This study aims to understand patients’ willingness to participate in a randomized trial comparing standard genetic counseling practice to personalized genetic counseling via LFSPRO risk estimates. Trial Design: Eligible patients or parents/guardians are invited via email to complete a survey assessing interest in a hypothetical clinical trial scenario where patients are randomized to receive one of two types of post-disclosure genetic counseling approaches: standard genetic counseling for TP53 results, involving generic risk predictions for developing cancers, or personalized risk information provided from LFSPRO. Following the hypothetical scenario, participants are asked about their perceived benefits and barriers to this research scenario and interest in receiving personalized risk results. Demographic information is also collected. Eligibility Criteria: Individuals who receive genetic counseling through MD Anderson Cancer Center genetics clinics specifically for TP53 genetic testing and who consent to undergo TP53 genetic testing or individuals who genetic testing already indicates a TP53 germline mutation are offered this survey. Patients must be 13 years or older to complete the survey, otherwise a parent/guardian may complete the survey on their behalf. Patients must have English fluency. Statistical methods: Descriptive statistics will be used to analyze the data and summarize the opinion of the participants. Accrual: Enrollment is set to open in July 2022. Currently, 157 patients have been identified to be invited to participate in the study. Funding: This research is supported by the Cancer Research and Prevention Institute of Texas. Contact: Jacynda Woodman-Ross, MS, CGC, The University of Texas MD Anderson Cancer Center, jawoodman@mdanderson.org

Citation Format: Jacynda Woodman-Ross, Sierra O. Green, Jessica Corredor, Elissa Dodd-Eaton, Nathaniel Hernandez, Susan K. Peterson, Wenyi Wang, Banu K. Arun. Willingness to Participate in a Trial Comparing Standard Genetic Counseling versus Genetic Counseling with Personalized Cancer Risks Estimates in Patients with Li-Fraumeni Syndrome [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 OT2-13-01.

Abstract OT1-15-01: SWOG 1904: Cluster-randomized controlled trial of patient and provider decision support to increase chemoprevention informed choice among women with atypical hyperplasia or lobular carcinoma in situ (MiCHOICE)

Background: Despite evidence of substantial breast cancer risk reduction, few high-risk women adopt chemopreventive medications such as selective estrogen receptor modulators (SERMs) or aromatase inhibitors (AIs). Women with benign breast disease, such as atypical hyperplasia (AH) or lobular carcinoma in situ (LCIS), have an increased risk of developing breast cancer and derive a greater benefit from antiestrogens compared to other high-risk women. Reasons for low uptake of chemoprevention include insufficient patient and clinician knowledge about antiestrogens, time constraints during the clinical encounter, and concerns about side effects. To address these barriers, we have developed patient and provider web-based decision support tools to improve informed choice about breast cancer chemoprevention among women with AH or LCIS. Study design: We are conducting a cluster-randomized controlled trial of clinical decision support to improve chemoprevention informed choice among women with AH or LCIS and their treating providers. Twenty-six U.S. sites through the SWOG Cancer Research Network were randomly assigned 1:1 to standard educational materials alone or in combination with the patient-centered decision aid (RealRisks) and provider decision support tool (BNAV). A total of 415 patients and 200 healthcare providers will be recruited from these sites. RealRisks consists of interactive modules to calculate personalized breast cancer risk and elicit preferences on chemoprevention. The modules are available in English and Spanish. BNAV is comprised of self-directed case-based learning modules on breast cancer risk assessment and chemoprevention. Patients complete questionnaires at baseline, 6 and 12 months. Providers complete surveys at baseline and after their enrolled patient’s 6-month clinical encounter. The primary endpoint is chemoprevention informed choice at 6 months, using a measure combining knowledge, attitude, and intention scales. Secondary endpoints include perceived breast cancer risk/worry, chemoprevention knowledge/intention, decision conflict/regret, shared decision-making, and chemoprevention uptake. For patients who begin chemoprevention, adherence and reasons for discontinuation are assessed annually for up to 5 years. Barriers and facilitators to implementing RealRisks and BNAV into clinic workflow will be assessed by conducting patient and provider interviews at baseline and mid-implementation. Eligibility criteria: Eligible patients include women, age 35-74 years, with AH or LCIS, no history of breast cancer, no prior use of SERMs or AIs, no bilateral mastectomies, English or Spanish-speaking, and access to the internet. Eligible providers include breast surgeons, medical oncologists, primary care providers, and physician extenders who see patients with AH or LCIS. Statistical methods: We have 90% power to detect a 15% increase in the frequency of chemoprevention informed choice with a 1-sided 0.025 level test, assuming an intraclass correlation (ICC) of 0.02 to account for clustering, roughly equal accrual at each site, 10% loss to follow-up, and ≤10% event rate in the control arm. Current/target accrual: The trial was activated on 9/1/2020. As of 7/7/2022, all 26 sites have been randomized, 157/200 providers and 184/415 patients have been enrolled. Discussion: Our hybrid effectiveness/implementation study seeks to evaluate the effectiveness of a multi-level intervention in promoting informed decision-making about breast cancer chemoprevention. Study results will provide valuable insights on how the decision support tools are integrated in diverse clinical settings.

Citation Format: Katherine D. Crew, Garnet Anderson, Kathryn Arnold, Andrew Stieb, Jacquelyn N. Amenta, Cynthia Law, Ana Sandoval-Leon, Sarah Colonna, Tari King, Debra Mangino, Sandhya Pruthi, Maria Grosse Perdekamp, Christa Braun-Inglis, Stacy Krisher, Lisa Yee, Danielle Bertoni, Samantha Seaward, Kari B. Wisinski, Justin Floyd, Corrine Zarwan, Tarah J. Ballinger, Lindi VanderWalde, Masey M. Ross, Preston Steen, Shelly Lo, Alison Conlin, Kathleen Yost, John Ellerton, Erin Lin, Holly J. Pederson, Sagar Sardesai, Cheryl Jernigan, Dawn Hershman, Marian L. Neuhouser, Banu K. Arun, Rita Kukafka. SWOG 1904: Cluster-randomized controlled trial of patient and provider decision support to increase chemoprevention informed choice among women with atypical hyperplasia or lobular carcinoma in situ (MiCHOICE) [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 OT1-15-01.

Abstract P4-06-09: A phase 1b study of neratinib with THP in metastatic and locally advanced breast cancer, and phase II study of THP followed by AC in HER2 + primary inflammatory breast cancer (IBC), and neratinib with taxol followed by AC in HR+/HER2- IBC

Background: The pathologic complete response (pCR) rate in inflammatory breast cancer (IBC) patients is worse than in non-IBC patients; new drug combinations are warranted to improve pCR rates across all IBC molecular subtypes. Based on our preclinical data, we added neratinib to standard neoadjuvant chemotherapy in both HER2+ (synergy) and HER2-/hormone receptor (HR)+ (high frequency of ERBB2 mut) untreated IBC, as a single-center, non-randomized phase I/II trial. Patients and Method: This study enrolled three cohorts: Cohort I phase Ib (C1P1B), Cohort I Phase II (C1P2) and Cohort II (C2). In C1P1B to determine the recommended phase 2 dose (RP2D), we enrolled patients with HER2+ metastatic or locally advanced breast cancer. Patients received paclitaxel/trastuzumab/pertuzumab (THP) + neratinib x 4 cycles (up to 8 cycles per physician’s discretion). For C1P2 and C2, we enrolled Stage III – IV primary IBC patients. In C1P2, patients with HER2+ IBC received neratinib (RP2D) combined with THP x 4 cycles followed by doxorubicin/cyclophosphamide (AC) x 4 cycles. Per stage I design, 11 patients were enrolled with plan to enroll 20 more patients in Stage II if at least 6 had a pCR. In C2, patients with HER2-/HR+ IBC received neratinib 200 mg/day combined with paclitaxel x 4 cycles followed by AC x 4 cycles. Stage I design planned for enrollment of 16 patients with enrollment of 15 more patients on stage II, if at least 2 Stage I patients had pCR. In all three cohorts, patients initiated prophylactic anti-diarrheal medication (loperamide & budesonide) with the first dose of neratinib. Results: From 2018 to 2022, thirty-four patients were enrolled and treated (n=4 C1P1B, n=14 C1P2, n=16 C2). In C1P1B, observed DLTs (dose limiting toxicities) were Grade (Gr) 2 Diarrhea, n=2 (50%); Gr3 diarrhea, n=2 (50%); 2 patients had a serious adverse event (SAE); 3 patients (55%) had Gr2 nausea. The RP2D was established at 80 mg/day (dose level 0). For patients in C1P2, the most frequently occurring adverse events (AEs) included Gr2 Alopecia, n=14 (100%); Gr2&3 Diarrhea, n=14 (100%); Gr2/3 Nausea, n=12 (86%); Gr2/3 Anemia, n=7 (50%); Gr2/3 Fatigue, n=8 (57%); Gr2/3 Hypokalemia, n=6 (57%); and Gr2/3 Neutrophil count decreased, n= 7 (50%). 6 patients had an SAE. Of the first 11 patients, 5 (46%) had pCR, 1 (9%) RCB-1, 1 (9%) RCB-II and 1 (9%) RCB-III. Three patients stopped study treatment for toxicity (27%), were non-evaluable and replaced. Of these, one had RCB-III (33.3%), one progression of disease (PD) (33.3%), and one came off study for toxicity (33.3%). Rather than replacing additional non-evaluable patients, the study was closed to new patient accrual. In C2, the most frequently occurring AEs were Gr2 diarrhea, n=7(44%); Gr3 diarrhea, n=8 (50%); Gr2 alopecia, n=14 (88%); Gr2/3 Anemia, n=10 (63%); Gr2/3 Nausea, n=7 (44%); Gr2/3 Neutropenia, n= 7 (44%). 3 patients had an SAE. Of 16 patients in this cohort, 1 had pCR (6%), 5 RCB-II (31%), 4 RCB-III (25%), 3 came off study for toxicity (19%) and 3 had PD (19%). C2 also closed to new patient accrual given the high toxicity profile. Conclusion: The addition of neratinib did not improve the pCR rate in HER2+ or HER2-/HR+ subtypes of IBC, and increased toxicities were observed. The trial closed to new patient entry March 2022. However, some patients achieved significant response. Biomarker analysis is ongoing. Evaluable participants will continue long-term follow-up per protocol. Acknowledgments: This study is supported by PUMA Biotechnology.

Citation Format: Angela N. Marx, Megumi Kai, Min Fu, Hope E. Murphy, Jie S. Willey, Huiming Sun, Angela Alexander, Roland L. Bassett, Gary J. Whitman, H. T. Carisa Le-Petross, Miral Patel, Banu K. Arun, Sausan Abouharb, Parijatham S. Thomas, Carlos H. Barcenas, Nuhad K. Ibrahim, Vicente Valero, Naoto T. Ueno, Rachel M. Layman, Bora Lim, Wendy Woodward, Anthony Lucci. A phase 1b study of neratinib with THP in metastatic and locally advanced breast cancer, and phase II study of THP followed by AC in HER2 + primary inflammatory breast cancer (IBC), and neratinib with taxol followed by AC in HR+/HER2- IBC [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 P4-06-09.

Abstract HER2-01: HER2-01 Clinical and Molecular Characteristics of HER2-low/zero Early Stage Triple-Negative Breast Cancer

Background: In the metastatic setting, low HER2 expression is associated with clinical benefit from trastuzumab deruxtecan, a HER2-targeting antibody drug conjugates. However, little is known about the biological significance of low HER2 expression in patients with early stage triple-negative breast cancer (TNBC) receiving neoadjuvant therapy (NAT). Methods: Out of 595 patients with stage I-III TNBC enrolled on the prospective ARTEMIS trial (NCT02276443) from 2015-2021, we identified 367 patients with available HER2 immunohistochemistry (IHC) results on pre-NAT tumor tissue (HER2-zero: n=218; HER2-low [IHC 1+, 2+]: n=149). All patients were treated with anthracycline-based NAT. In cases where sufficient pre-NAT tumor tissue were available, additional IHC and/or RNAseq were performed. Differential gene expression (DGE) and pathway analysis were performed using DEseq2. Gene set enrichment analysis (GSEA) was performed using the Hallmark gene sets. Deconvolution analyses were performed using CIBERSORT. We controlled for multiple hypothesis using a false discovery rate (FDR) threshold with the Benjamini-Hochberg method, accepting as significant genes with at least a 2-fold change and < 5% FDR. Results: Table 1 summarizes baseline clinicopathological features of the 367 patients. Compared to HER2-zero tumors, HER2-low tumors were less likely of metaplastic histology (p=0.001), associated with lower Ki67 (p=0.017) and were more likely to be androgen receptor (AR)-positive (p=0.01). There were no significant differences in tumor-infiltrating lymphocytes (TILs) infiltration and PD-L1 expression between HER2-zero and HER2-low tumors. Among the 226 patients with sufficient pre-NAT tissue for RNAseq, DGE analyses demonstrated upregulation of genes involved in fatty acid metabolism (ACSM1) and steroid hormone metabolism (DHRS2, UGT2B28) in HER2-low tumors compared with HER2-zero tumors. Deconvolution analyses revealed no significant differences between predicted proportions of immune cell subpopulations between HER2-low and HER2-zero tumors. Although rates of pCR were not significantly different between patients with HER2-zero (46%) and HER2-low tumors (40%) (p=0.34), non-pCR in patients with HER2-low tumors was associated with increased expression of EREG, which encodes an EGFR ligand, while non-pCR in patients with HER2-zero tumors was associated with downregulation in genes involved in immune response pathways. GSEA further identified the Hallmark allograft rejection (FDR q=0.001), interferon gamma response (FDR q=0.002), and interferon alpha response pathways (FDR q=0.007) as the 3 most significantly downregulated pathways in HER2-zero tumors from patients experiencing a non-pCR relative to HER2-zero tumors from patients experiencing a pCR. Conclusion: In early stage TNBC, low HER2 expression is associated with increased AR expression and upregulation of genes associated with fatty acid and steroid hormone metabolism. Gene expression analyses suggest that drivers of resistance to NAT differ between HER2-low and HER2-zero tumors. Biological differences between HER2-zero and HER2-low tumors exist and may influence future personalized treatment for patients with early stage TNBC.

Citation Format: Clinton Yam, Ziyi Li, Anil Korkut, Wencai Ma, Elisabeth Kong, Holly A. Hill, Hussein Abbas, Sausan Abouharb, Beatriz Adrada, Banu K. Arun, Carlos H. Barcenas, Ajit Bisen, Daniel Booser, Aman Buzdar, Rosalind Candelaria, Junjie Chen, Alyson Clayborn, Senthil Damodaran, Qingqing Ding, Haven Garber, Gabriel N. Hortobagyi, Kelly K. Hunt, Nuhad K. Ibrahim, Adaeze Iheme, Meghan S. Karuturi, Kimberly Koenig, Rachel M. Layman, Jangsoon Lee, Jennifer K. Litton, Melissa Mitchell, Giancarlo Moscol, Jason Mouabbi, Rashmi K. Murthy, Oluchi Oke, Paula Pohlmann, David Ramirez, Elizabeth Ravenberg, Sadia Saleem, Mediget Teshome, Vicente Valero, Jason White, Madison Williams, Wendy Woodward, Chasity Yajima, Naoto T. Ueno, Ken Chen, Gaiane Rauch, Lei Huo, Debu Tripathy. HER2-01 Clinical and Molecular Characteristics of HER2-low/zero Early Stage Triple-Negative 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 HER2-01.

Abstract OT2-12-01: Clinical Application of LFSPRO: A Prospective Study

Background: Individuals with Li-Fraumeni Syndrome (LFS) have increased risk of developing cancers of several types, such as early-onset breast cancer, soft-tissue/bone sarcoma, leukemia, brain tumors, and more, throughout their lifetime. LFS is primarily caused by autosomal dominant germline mutations in the TP53 tumor suppressor gene. It is difficult to identify TP53 mutation carriers because of the overlap in the occurrence of multiple cancer types in LFS with other inherited cancer syndromes. In order to improve the accuracy of risk assessment for these families, the LFSPRO risk model was created to predict the likelihood of a proband having LFS based off detailed patient and family history information, as well as predict cancer-specific risks for patients who have already been identified as having LFS. Specific Aims: The primary aim of this study is to evaluate the concordance of LFSPRO and clinical criteria in predicting TP53 mutation status in patients undergoing germline TP53 testing. Trial Design: After receiving standard genetic counseling, patients identified as concerning for a potential TP53 mutation by a MD Anderson genetic counselor (GC) are run through LFSPRO. LFSPRO TP53 mutation carrier risk, whether the patient meets Chompret and/or Classic criteria, decision to test, and genetic test results are collected. Select GCs are then asked to complete a survey regarding their experience with LFSPRO. Eligibility Criteria: Through standard genetic counseling practice, MD Anderson GCs identify patients with a clinical suspicion for a TP53 germline mutation. All patients identified are run through LFSPRO. Out of these identified patients, select GCs that participated in the initial genetic counseling session are asked to complete a survey over their experience using the LFSPRO. Statistical methods: We will evaluate the concordance in the prediction of TP53 mutation carrier status between LFSPRO and current clinical criteria as compared to the outcome of genetic testing results. We will cross-tabulate the predicted TP53-mutation status (positive vs. negative) with the carrier status in a 2 × 2 table and calculate the sensitivity and specificity of each prediction tool separately (LFSPRO, clinical criteria), with 95% confidence interval. Accrual: Currently, 72 patients have been run through LFSPRO. Select GCs have completed the survey regarding their experience with LFSPRO on 20 of these patients. Data collection began in December 2021 and is currently ongoing. Funding: This research is supported by the Cancer Research and Prevention Institute of Texas. Contact: Jacynda Woodman-Ross, MS, CGC, The University of Texas MD Anderson Cancer Center, jawoodman@mdanderson.org

Citation Format: Jacynda Woodman-Ross, Elissa Dodd-Eaton, Jessica Corredor, Sierra O. Green, Nam H. Nguyen, Nathaniel Hernandez, Courtney D. DiNardo, Wenyi Wang, Banu K. Arun. Clinical Application of LFSPRO: A Prospective Study [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 OT2-12-01.

Abstract P6-02-04: Use of breast surveillance between women with pathogenic variants and variants of uncertain significance in breast cancer susceptibility genes

Background: Surveillance is a fundamental tool in the early detection and secondary prevention of many cancers. For women at increased genetic risk of breast cancer, mammography and breast magnetic resonance imaging (MRI) serve as the standard screening modalities. Use of surveillance mammography and MRI has been understudied among women with variant of uncertain significance (VUS) compared to pathogenic and likely pathogenic variants (P/LP). To address this gap, we examined the use of breast cancer surveillance and breast surgery in women who underwent multiple gene sequencing in a multicenter cohort of patients. We also expanded the surveillance literature by assessing correlates of breast MRI and mammography among women with VUS and investigating how rates of imaging changed over time after genetic testing. Methods: Using data from two cancer settings, we calculated use of risk reducing mastectomy (RRM) and surveillance for all women at genetically elevated risk of breast cancer, regardless of their personal history of breast cancer, with VUS or P/LP variants in a breast cancer susceptibility gene of high penetrance (BRCA1, BRCA2, PALB2, PTEN, TP53) and moderate penetrance (ATM, CDH1, CHEK2, NBN, NF1, STK11). The primary outcome was longitudinal use of surveillance mammography and breast MRI for women during the 13-month span after genetic testing, and each subsequent 13-month period up to 6 years afterwards. Results: Of 889 women, those with and without personal history of breast cancer were similar with regards to race/ethnicity, marital status, and high- or average-risk status. However, women with a personal history of breast cancer were on average older (54.1 vs 48.2 years), had longer follow-up time since genetic testing (3.4 vs 3.0 years), and were more likely to have VUS (62.5% vs 37.7%) compared to those without personal history of breast cancer. VUS carriers were less likely to undergo RRM compared to those with P/LP (HR=0.17, p=< 0.001) and high-risk women were more likely to undergo RRM than average-risk women (HR=3.91, p=0.005). Longitudinally, surveillance use among unaffected women decreased from 49.8% in the first year to 31.2% in the sixth year after genetic testing. In comparison, a greater proportion of women with a personal history of breast cancer underwent surveillance, which increased from 59.3% in the first year to 63.6% in the sixth year after genetic testing. Mammography rates did not differ between women with P/LP and VUS within the first 13 months after genetic testing and up to 4 years afterwards. Over the first four years after genetic testing, women with VUS were less likely to undergo annual MRIs compared to P/LP. This observation was true for women without a personal history of breast cancer (OR=0.34, p=0.003; OR=0.37, p=0.03; OR=0.19, p=0.004 for years 1, 2, and 3 respectively) as well as for women with a personal history of breast cancer (OR=0.31, p<=0.001; OR=0.33, p=0.002; OR=0.37, p=0.012; OR=0.3, p=0.14 for years 1, 2, 3, and 4 respectively). Conclusion: In this study of surveillance mammography and breast MRI use among women at elevated risk of breast cancer, we found that women with P/LP variants in breast cancer susceptibility genes are more likely to undergo annual breast MRI compared to those with VUS, whereas there was no difference between the groups in their use of annual surveillance mammography. This study is one of the first to examine maintenance of breast surveillance in a sample of women at elevated risk of breast cancer with non-negative genetic test results in BRCA1/2 as well as non-BRCA1/2 genes, while adjusting for personal and family history of cancer. In addition, we found that VUS, whether in high or moderate penetrance breast cancer susceptibility genes, was associated with lower use of annual breast MRI compared to P/LP variants, and equivalent use of annual mammography. These results add important evidence to dispel the myth of VUS-associated mismanagement of care.

Citation Format: Sukh Makhnoon, Minxing Chen, Brooke Levin, Megan Ensinger, Kristin Mattie, Generosa Grana, Sanjay Shete, Banu K. Arun, Susan K. Peterson. Use of breast surveillance between women with pathogenic variants and variants of uncertain significance in breast cancer susceptibility genes [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 P6-02-04.

Other Primary Malignancies in Patients with Breast Cancer Who Undergo Germline Panel Testing

BACKGROUND

Women with a history of breast cancer (BC) more commonly have a diagnosis of other primary malignancies (OPMs) than the general population. This study sought to evaluate OPMs among patients with BC who underwent germline testing with a hereditary BC gene panel.

METHODS

The study identified women 18 years of age or older with a history of unilateral BC who underwent multi-gene panel testing between January 2014 and August 2019 at the authors' institution. Patient, tumor, and treatment factors for BC and OPM diagnoses were collected for descriptive, univariate, and overall survival (OS) analyses.

RESULTS

Among 1163 patients, 330 (28.4%) had an OPM. The median follow-up period was 4.1 years from BC diagnosis. Of the 1163 patients, 209 (18%) had a BRCA pathogenic variant (PV), 306 (26.4%) had a non-BRCA PV, and 648 (55.7%) had no PV. Development of an OPM varied according to germline testing result, with an OPM developing for 18.6% (39/209) of the patients with a BRCA PV, 31.8% (204/648) of the patients with no PV, and 28.4% (87/306) of the patients with a non-BRCA PV (p < 0.0001). The most common OPMs were ovarian (n = 60), uterine (n = 44), sarcoma (n = 36), melanoma (n = 27), colorectal (n = 22), and lymphoma (n = 20) malignancies. The 5-year OS was 96%. The patients with an OPM 5 years after BC diagnosis had a shorter OS than those who did not (93.4% vs 97.5%; p = 0.002).

CONCLUSION

More than 25% of women with BC who underwent germline panel testing had an OPM diagnosed during the short-term follow-up period, and the diagnosis of an OPM was associated with reduced OS. These data have implications for counseling BC patients who undergo germline testing regarding future cancer screening.

Copy number variants as modifiers of breast cancer risk for BRCA1/BRCA2 pathogenic variant carriers

The contribution of germline copy number variants (CNVs) to risk of developing cancer in individuals with pathogenic BRCA1 or BRCA2 variants remains relatively unknown. We conducted the largest genome-wide analysis of CNVs in 15,342 BRCA1 and 10,740 BRCA2 pathogenic variant carriers. We used these results to prioritise a candidate breast cancer risk-modifier gene for laboratory analysis and biological validation. Notably, the HR for deletions in BRCA1 suggested an elevated breast cancer risk estimate (hazard ratio (HR) = 1.21), 95% confidence interval (95% CI = 1.09-1.35) compared with non-CNV pathogenic variants. In contrast, deletions overlapping SULT1A1 suggested a decreased breast cancer risk (HR = 0.73, 95% CI 0.59-0.91) in BRCA1 pathogenic variant carriers. Functional analyses of SULT1A1 showed that reduced mRNA expression in pathogenic BRCA1 variant cells was associated with reduced cellular proliferation and reduced DNA damage after treatment with DNA damaging agents. These data provide evidence that deleterious variants in BRCA1 plus SULT1A1 deletions contribute to variable breast cancer risk in BRCA1 carriers.

Use of breast surveillance between women with pathogenic variants and variants of uncertain significance in breast cancer susceptibility genes

BACKGROUND

Use of surveillance mammography and magnetic resonance imaging (MRI) has been understudied among women with variant of uncertain significance (VUS) compared to pathogenic and likely pathogenic variants (P/LP).

METHODS

Using data from two cancer settings, we calculated use of risk-reducing mastectomy (RRM) and surveillance during each 13-month span after genetic testing up to 6 years afterwards for a cohort of genetically elevated risk women.

RESULTS

Of 889 women, VUS carriers were less likely to undergo RRM compared to those with P/LP (hazard ratio [HR], 0.17; p = <.001) and high-risk women were more likely to undergo RRM than average-risk women (HR, 3.91; p = .005). Longitudinally, surveillance use among unaffected women decreased from 49.8% in the first year to 31.2% in the sixth year after genetic testing. In comparison, a greater proportion of women with a personal history of breast cancer underwent surveillance, which increased from 59.3% in the first year to 63.6% in the sixth year after genetic testing. Mammography rates did not differ between women with P/LP and VUS within the first 13 months after genetic testing and up to 4 years afterward. Over the first 4 years after genetic testing, women with VUS were less likely to undergo annual MRIs compared to P/LP.

CONCLUSION

The authors found that VUS, whether in high or moderate penetrance breast cancer susceptibility genes, was associated with lower use of annual breast MRI compared to P/LP variants and equivalent use of annual mammography. These results add important evidence regarding VUS-related breast surveillance.

Tumor Immune Microenvironment Changes by Multiplex Immunofluorescence Staining in a Pilot Study of Neoadjuvant Talazoparib for Early-Stage Breast Cancer Patients with a Hereditary BRCA Mutation

PURPOSE

The immunological profile of early-stage breast cancer treated with neoadjuvant PARP inhibitors has not been described. The aim of this study was to delineate the changes in the tumor immune microenvironment (TiME) induced by talazoparib.

PATIENTS AND METHODS

Patients with operable germline BRCA1/2 pathogenic variant (gBRCA1/2+) breast cancer were enrolled in a feasibility study of neoadjuvant talazoparib. Thirteen patients who received 8 weeks of neoadjuvant talazoparib were available for analysis, including 11 paired pre- and post-talazoparib core biopsies. Treatment-related changes in tumor-infiltrating lymphocytes were examined and immune cell phenotypes and their spatial distribution in the TiME were identified and quantified by multiplex immunofluorescence using a panel of 6 biomarkers (CD3, CD8, CD68, PD-1, PD-L1, and CK).

RESULTS

Neoadjuvant talazoparib significantly increased infiltrating intratumoral and stromal T-cell and cytotoxic T-cell density. There was no difference in PD-1 or PD-L1 immune cell phenotypes in the pre- and post-talazoparib specimens and PD-L1 expression in tumor cells was rare in this cohort. Spatial analysis demonstrated that pre-talazoparib interactions between macrophages and T cells may correlate with pathologic complete response.

CONCLUSIONS

This is the first study with phenotyping to characterize the immune response to neoadjuvant talazoparib in patients with gBRCA1/2+ breast cancer. These findings support an emerging role for PARP inhibitors in enhancing tumor immunogenicity. Further investigation of combinatorial strategies is warranted with agents that exploit the immunomodulatory effects of PARP inhibitors on the TiME.

Long-Term Adaptation Among Adolescent and Young Adult Children to Familial Cancer Risk

BACKGROUND

It is important to examine adolescent and young adult (AYA) children's long-term psychosocial and behavioral adaptation to disclosure of maternal BRCA-positive carrier status (BRCA+) to inform approaches for familial cancer risk communication, education, and counseling.

METHODS

Mothers underwent BRCA genetic testing 1 to 5 years earlier. Group differences in AYAs' self-reported outcomes were analyzed by maternal health and carrier status, and child age and sex.

RESULTS

A total of N = 272 AYAs were enrolled: 76.1% of their mothers were breast or ovarian cancer survivors and 17.3% were BRCA+. AYAs' cancer risk behavior (tobacco and alcohol use, physical activity) and psychologic distress levels did not vary by maternal status. In bivariate analyses, AYAs of cancer-surviving mothers believed themselves to be at greater risk for, and were more knowledgeable about, cancer than AYAs of mothers without cancer. AYAs of BRCA+ mothers were more concerned about cancer, held stronger beliefs about genetic risk, and placed a higher value on learning about genetics. In adjusted models, maternal cancer history (not BRCA+) remained associated with AYAs' greater perceptions of cancer risk (P = .002), and knowledge about cancer (P = .03) and its causes (P = .002).

CONCLUSIONS

Disclosing maternal BRCA+ status did not influence children's lifestyle behavior or adversely affect quality of life long term. AYAs of BRCA+ mothers were more aware of and interested in genetic risk information. Such families may benefit from support to promote open communication about genetic testing choices.

Molecular Characterization and Prospective Evaluation of Pathologic Response and Outcomes with Neoadjuvant Therapy in Metaplastic Triple-Negative Breast Cancer

PURPOSE

Metaplastic breast cancer (MpBC) is a rare subtype of breast cancer that is commonly triple-negative and poorly responsive to neoadjuvant therapy in retrospective studies.

EXPERIMENTAL DESIGN

To better define clinical outcomes and correlates of response, we analyzed the rate of pathologic complete response (pCR) to neoadjuvant therapy, survival outcomes, and genomic and transcriptomic profiles of the pretreatment tumors in a prospective clinical trial (NCT02276443). A total of 211 patients with triple-negative breast cancer (TNBC), including 39 with MpBC, received doxorubicin-cyclophosphamide-based neoadjuvant therapy.

RESULTS

Although not meeting the threshold for statistical significance, patients with MpBCs were less likely to experience a pCR (23% vs. 40%; P = 0.07), had shorter event-free survival (29.4 vs. 32.2 months, P = 0.15), metastasis-free survival (30.3 vs. 32.4 months, P = 0.22); and overall survival (32.6 vs. 34.3 months, P = 0.21). This heterogeneity is mirrored in the molecular profiling. Mutations in PI3KCA (23% vs. 9%, P = 0.07) and its pathway (41% vs. 18%, P = 0.02) were frequently observed and enriched in MpBCs. The gene expression profiles of each histologically defined subtype were distinguishable and characterized by distinctive gene signatures. Among nonmetaplastic (non-Mp) TNBCs, 10% possessed a metaplastic-like gene expression signature and had pCR rates and survival outcomes similar to MpBC.

CONCLUSIONS

Further investigations will determine if metaplastic-like tumors should be treated more similarly to MpBC in the clinic. The 23% pCR rate in this study suggests that patients with MpBC should be considered for NAT. To improve this rate, a pathway analysis predicted enrichment of histone deacetylase (HDAC) and RTK/MAPK pathways in MpBC, which may serve as new targetable vulnerabilities.

Identification of biomarkers of response to preoperative talazoparib monotherapy in treatment naïve gBRCA+ breast cancers

Germline mutations in BRCA1 or BRCA2 exist in ~2–7% of breast cancer patients, which has led to the approval of PARP inhibitors in the advanced setting. We have previously reported a phase II neoadjuvant trial of single agent talazoparib for patients with germline BRCA pathogenic variants with a pathologic complete response (pCR) rate of 53%. As nearly half of the patients treated did not have pCR, better strategies are needed to overcome treatment resistance. To this end, we conducted multi-omic analysis of 13 treatment naïve breast cancer tumors from patients that went on to receive single-agent neoadjuvant talazoparib. We looked for biomarkers that were predictive of response (assessed by residual cancer burden) after 6 months of therapy. We found that all resistant tumors exhibited either the loss of SHLD2, expression of a hypoxia signature, or expression of a stem cell signature. These results indicate that the deep analysis of pre-treatment tumors can identify biomarkers that are predictive of response to talazoparib and potentially other PARP inhibitors, and provides a framework that will allow for better selection of patients for treatment, as well as a roadmap for the development of novel combination therapies to prevent emergence of resistance.

Polygenic risk modeling for prediction of epithelial ovarian cancer risk

Polygenic risk scores (PRS) for epithelial ovarian cancer (EOC) have the potential to improve risk stratification. Joint estimation of Single Nucleotide Polymorphism (SNP) effects in models could improve predictive performance over standard approaches of PRS construction. Here, we implemented computationally efficient, penalized, logistic regression models (lasso, elastic net, stepwise) to individual level genotype data and a Bayesian framework with continuous shrinkage, "select and shrink for summary statistics" (S4), to summary level data for epithelial non-mucinous ovarian cancer risk prediction. We developed the models in a dataset consisting of 23,564 non-mucinous EOC cases and 40,138 controls participating in the Ovarian Cancer Association Consortium (OCAC) and validated the best models in three populations of different ancestries: prospective data from 198,101 women of European ancestries; 7,669 women of East Asian ancestries; 1,072 women of African ancestries, and in 18,915 BRCA1 and 12,337 BRCA2 pathogenic variant carriers of European ancestries. In the external validation data, the model with the strongest association for non-mucinous EOC risk derived from the OCAC model development data was the S4 model (27,240 SNPs) with odds ratios (OR) of 1.38 (95% CI: 1.28-1.48, AUC: 0.588) per unit standard deviation, in women of European ancestries; 1.14 (95% CI: 1.08-1.19, AUC: 0.538) in women of East Asian ancestries; 1.38 (95% CI: 1.21-1.58, AUC: 0.593) in women of African ancestries; hazard ratios of 1.36 (95% CI: 1.29-1.43, AUC: 0.592) in BRCA1 pathogenic variant carriers and 1.49 (95% CI: 1.35-1.64, AUC: 0.624) in BRCA2 pathogenic variant carriers. Incorporation of the S4 PRS in risk prediction models for ovarian cancer may have clinical utility in ovarian cancer prevention programs.

Clinical outcomes and Oncotype DX Breast Recurrence Score® in early-stage BRCA-associated hormone receptor-positive breast cancer

Background

BRCA‐associated breast cancers tend to have distinctive features compared to sporadic breast cancers; further characterization can aid in optimizing treatment.

Methods

The study evaluated a patient cohort with early‐stage estrogen receptor positive, HER2 negative invasive breast cancer who had Oncotype DX Breast Recurrence Score® analysis and genetic testing for hereditary breast and ovarian cancer syndrome. Data on patients and their breast cancers with outcomes were collected and analyzed.

Results

745 patients were included, of whom 33 had pathogenic BRCA mutations (8 BRCA1, 25 BRCA2). Patients with BRCA mutations were younger and received more adjuvant chemotherapy, but less endocrine therapy and radiation therapy. BRCA‐associated breast cancers had less progesterone receptor expression, higher nuclear grade, and higher Oncotype DX Breast Recurrence Scores® with median Recurrence Score® 29, compared to 16 in cancers without mutations (p < 0.0001). Breast cancer recurrence developed in 18% of patients with BRCA mutations and 9% of patient without mutations, although multivariate analysis of relapse‐free survival was not significant, HR 1.519 (95% confidence interval [CI] 0.64–3.58; p = 0.3401). After adjusting for Recurrence Score®, overall survival by BRCA status was improved HR 0.448 (95% CI 0.06–3.34; p = 0.4333).

Conclusions

BRCA‐associated early‐stage hormone receptor‐positive breast cancers have higher Oncotype DX Breast Recurrence Score® compared to those without mutations. BRCA status did not significantly impact relapse‐free survival and overall survival. Larger clinical trials are needed to further assess the findings, and if confirmed, could impact clinical management of BRCA‐associated breast cancers.

Outcomes After Breast Radiation Therapy in a Diverse Patient Cohort With a Germline BRCA1/2 Mutation

PURPOSE

BRCA1/2 pathogenic variant (PV) mutations confer radiation sensitivity preclinically, but there are limited data regarding breast cancer outcomes after radiation therapy (RT) among patients with documented BRCA1/2 PV mutations versus no PV mutations.

METHODS AND MATERIALS

This retrospective cohort study included women with clinical stage I-III breast cancer who received definitive surgery and RT and underwent BRCA1/2 genetic evaluation at the The University of Texas MD Anderson Cancer Center. Rates of locoregional recurrence (LRR), disease-specific death (DSD), toxicities, and second cancers were compared by BRCA1/2 PV status.

RESULTS

Of the 2213 women who underwent BRCA1/2 testing, 63% self-reported their race as White, 13.6% as Black/African American, 17.6% as Hispanic, and 5.8% as Asian/American Indian/Alaska Native; 124 had BRCA1 and 100 had BRCA2 mutations; and 1394 (63%) received regional nodal RT. The median follow-up time for all patients was 7.4 years (95% confidence interval [CI], 7.1-7.7 years). No differences were found between the groups with and without BRCA1/2 PV mutations in 10-year cumulative incidences of LRR (with mutations: 11.6% [95% CI, 7.0%-17.6%]; without mutations: 6.6% [95% CI, 5.3%-8.0%]; P = .466) and DSD (with mutations: 12.3% [95% CI, 8.0%-17.7%]; without mutations: 13.8% [95% CI, 12.0%-15.8%]; P = .716). On multivariable analysis, BRCA1/2 status was not associated with LRR or DSD, but Black/African American patients (P = .036) and Asians/American Indians/Alaska Native patients (P = .002) were at higher risk of LRR compared with White patients, and Black/African American patients were at higher risk of DSD versus White patients (P = .004). No in-field, nonbreast second cancers were observed in the BRCA1/2 PV group. Rates of acute and late grade ≥3 radiation-related toxicity in the BCRA1/2 PV group were 5.4% (n = 12) and 0.4% (n = 1), respectively.

CONCLUSIONS

Oncologic outcomes in a diverse cohort of patients with breast cancer who had a germline BRCA1/2 PV mutation and were treated with RT were similar to those of patients with no mutation, supporting the use of RT according to standard indications in patients with a germline BRCA1/2 PV mutation.

Breast Radiation Therapy-Related Treatment Outcomes in Patients With or Without Germline Mutations on Multigene Panel Testing

PURPOSE

Multigene panel testing has increased the detection of germline mutations in patients with breast cancer. The implications of using radiation therapy (RT) to treat patients with pathogenic variant (PV) mutations are not well understood and have been studied mostly in women with only BRCA1 or BRCA2 PVs. We analyzed oncologic outcomes and toxicity after adjuvant RT in a contemporary, diverse cohort of patients with breast cancer who underwent genetic panel testing.

METHODS AND MATERIALS

We retrospectively reviewed the records of 286 women with clinical stage I-III breast cancer diagnosed from 1995 to 2017 who underwent surgery, breast or chest wall RT with or without regional nodal irradiation, multigene panel testing, and evaluation at a large cancer center's genetic screening program. We evaluated rates of overall survival, locoregional recurrence, disease-specific death, and radiation-related toxicities in 3 groups: BRCA1/2 PV carriers, non-BRCA1/2 PV carriers, and patients without PV mutations.

RESULTS

PVs were detected in 25.2% of the cohort (12.6% BRCA1/2 and 12.6% non-BRCA1/2). The most commonly detected non-BRCA1/2 mutated genes were ATM, CHEK2, PALB2, CDH1, TP53, and PTEN. The median follow-up time for the entire cohort was 4.4 years (95% confidence interval, 3.8-4.9 years). No differences were found in overall survival, locoregional recurrence, or disease-specific death between groups (P > .1 for all). Acute and late toxicities were comparable across groups.

CONCLUSION

Oncologic and toxicity outcomes after RT in women with PV germline mutations detected by multigene pane testing are similar to those in patients without detectable mutations, supporting the use of adjuvant RT as a standard of care when indicated.

Increasing referral of at-risk women for genetic counseling and BRCA testing using a screening tool in a community breast imaging center

BACKGROUND

Genetic evaluation and testing for hereditary breast and ovarian cancer (HBOC) remain suboptimal. The authors evaluated the feasibility of using a screening tool at a breast imaging center to increase HBOC assessment referrals.

METHODS

A brief questionnaire based on the National Comprehensive Cancer Network HBOC genetic counseling referral guidelines was developed and added to the standard intake forms of patients undergoing mammography at a community breast imaging center from 2012 through 2015. Patients who met the criteria in the guidelines were referred for genetic counseling.

RESULTS

A total of 34,851 patients were screened during the study period, and 1246 (4%) patients were found to be eligible for referral; 245 of these patients made a genetic counseling appointment, and 142 patients received genetic counseling. Forty patients (28%) had a personal history of breast cancer but were not previously tested. Following counseling, 105 patients were tested for BRCA1/2. Eight patients (8%) tested positive for a pathogenic mutation and nine (9%) had a variant of unknown significance. Although they tested negative, many patients met the criteria to add breast magnetic resonance imaging to their screening due to greater than 20% lifetime breast cancer risk based on their family cancer history. This study led to improved clinical risk management in 67% of the patients who underwent genetic counseling.

CONCLUSIONS

This study shows that large-scale screening of patients for HBOC syndromes at time of breast imaging is practical and highly feasible. The screening tool identified women with actionable BRCA1/2 mutations and mutation-negative but high-risk women, leading to significant changes in their risk management; these women would otherwise have been missed.

LAY SUMMARY

Hereditary breast and ovarian cancer (HBOC) caused by pathogenic mutations in breast cancer genes (BRCA1/BRCA2) increase an individual's lifetime risk of getting HBOC. Identifying these high-risk individuals and using proven preventive clinical risk management strategies can significantly reduce their lifetime risk of HBOC. Using an innovative family cancer history questionnaire, 34,000 women were screened at a community breast imaging center, and genetic counseling and testing were provided to eligible women from the screening. Several women at high risk for HBOC were identified and this led to positive clinical risk management changes. These women would have been missed if not for intervention.

Safety and efficacy of veliparib plus carboplatin/paclitaxel in patients with HER2-negative metastatic or locally advanced breast cancer: subgroup analyses by germline BRCA1/2 mutations and hormone receptor status from the phase-3 BROCADE3 trial

Purpose

To evaluate efficacy and safety of veliparib combined with carboplatin/paclitaxel in patients with advanced human epidermal growth factor receptor 2 (HER2)-negative, germline BRCA (gBRCA)-associated breast cancer defined by hormone receptor (HR) and gBRCA1/2 mutation status.

Patients and Methods

In this phase-3, double-blind, placebo-controlled trial, patients (N = 509) with advanced HER2-negative breast cancer and gBRCA1/2 mutations were randomized 2:1 to receive veliparib plus carboplatin/paclitaxel or placebo plus carboplatin/paclitaxel. Patients who discontinued chemotherapy prior to disease progression continued receiving blinded veliparib/placebo monotherapy. The primary endpoint was investigator-assessed progression-free survival (PFS). Subgroup analyses of PFS stratified by HR and gBRCA1/2 mutation status were prespecified.

Results

In the intention-to-treat population, there were similar proportions of patients with gBRCA1 versus gBRCA2 mutations (51% vs 49%) and HR+ disease versus triple-negative breast cancer (TNBC) (52% vs 48%). Median PFS was longer in the veliparib arm compared with the placebo arm for all subgroups (HR+: 13.0 vs 12.5 months, hazard ratio (95% confidence interval (CI)): 0.69 (0.52, 0.93), p = 0.013; TNBC: 16.6 vs 14.1 months, hazard ratio (95% CI): 0.72 (0.52, 1.00), p = 0.052; gBRCA1: 14.2 vs 12.6 months, hazard ratio (95% CI): 0.75 (0.55, 1.03), p = 0.073; gBRCA2: 14.6 vs 12.6 months, hazard ratio (95% CI): 0.69 (0.50, 0.95); p = 0.021). Benefit was durable, with improved PFS rates at 2 years (HR+, 27.5% vs 15.3%; TNBC, 40.4% vs 25.0%) and 3 years (HR+, 17.5% vs 8.6%; TNBC, 35.3% vs 13.0%) in all subgroups. gBRCA status (BRCA1 vs BRCA2) did not substantially affect the carboplatin/paclitaxel ± veliparib toxicity profile.

Conclusion

Veliparib plus carboplatin/paclitaxel resulted in durable benefit in subgroups defined by HR status or by gBRCA1 versus gBRCA2 mutation. Overall, addition of veliparib to carboplatin/paclitaxel was tolerable, and there were no clinically meaningful differences in adverse events between the gBRCA1 versus gBRCA2 and HR+ versus TNBC subgroups.

Trial Registration

NCT02163694, https://clinicaltrials.gov/ct2/show/NCT02163694.

Relevance of Platinum-free Interval and BRCA Reversion Mutations for Veliparib Monotherapy after Progression on Carboplatin/Paclitaxel for gBRCA Advanced Breast Cancer (BROCADE3 Crossover)

PURPOSE

Safety, efficacy, and exploratory biomarker analyses were evaluated in patients with advanced HER2-negative germline breast cancer susceptibility gene (gBRCA)-associated breast cancer enrolled in the BROCADE3 trial who received crossover veliparib monotherapy after disease progression on placebo plus carboplatin/paclitaxel.

PATIENTS AND METHODS

Eligible patients (N = 513) were randomized 2:1 to veliparib plus carboplatin/paclitaxel or placebo plus carboplatin/paclitaxel; patients had variable platinum-free intervals (PFI) at progression. In the placebo arm, patients were eligible to receive crossover veliparib monotherapy (300-400 mg twice daily continuous). Antitumor activity and adverse events were assessed during crossover veliparib treatment. BRCA reversion mutations at crossover were analyzed retrospectively using next-generation sequencing on plasma circulating tumor DNA (ctDNA).

RESULTS

Seventy-five patients in the placebo plus carboplatin/paclitaxel arm received ≥1 dose of crossover veliparib postprogression (mean treatment duration: 154 days). Eight of 50 (16%) patients with measurable disease had a RECIST v1.1 response. Activity was greater in patients with PFI ≥180 days compared with <180 days [responses in 23.1% (3/13) vs. 13.5% (5/37) of patients]. BRCA reversion mutations that restored protein function were detected in ctDNA from 4 of 28 patients tested, and the mean duration of crossover veliparib monotherapy was <1 month in these 4 patients versus 7.49 months in patients lacking reversion mutations. The most frequent adverse events were nausea (61%), vomiting (29%), and fatigue (24%).

CONCLUSIONS

Crossover veliparib monotherapy demonstrated limited antitumor activity in patients who experienced disease progression on placebo plus carboplatin/paclitaxel. PFI appeared to affect veliparib activity. BRCA reversion mutations may promote cross-resistance and limit veliparib activity following progression on platinum.

The predictive ability of the 313 variant-based polygenic risk score for contralateral breast cancer risk prediction in women of European ancestry with a heterozygous BRCA1 or BRCA2 pathogenic variant

PURPOSE

To evaluate the association between a previously published 313 variant-based breast cancer (BC) polygenic risk score (PRS313) and contralateral breast cancer (CBC) risk, in BRCA1 and BRCA2 pathogenic variant heterozygotes.

METHODS

We included women of European ancestry with a prevalent first primary invasive BC (BRCA1 = 6,591 with 1,402 prevalent CBC cases; BRCA2 = 4,208 with 647 prevalent CBC cases) from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA), a large international retrospective series. Cox regression analysis was performed to assess the association between overall and ER-specific PRS313 and CBC risk.

RESULTS

For BRCA1 heterozygotes the estrogen receptor (ER)-negative PRS313 showed the largest association with CBC risk, hazard ratio (HR) per SD = 1.12, 95% confidence interval (CI) (1.06-1.18), C-index = 0.53; for BRCA2 heterozygotes, this was the ER-positive PRS313, HR = 1.15, 95% CI (1.07-1.25), C-index = 0.57. Adjusting for family history, age at diagnosis, treatment, or pathological characteristics for the first BC did not change association effect sizes. For women developing first BC < age 40 years, the cumulative PRS313 5th and 95th percentile 10-year CBC risks were 22% and 32% for BRCA1 and 13% and 23% for BRCA2 heterozygotes, respectively.

CONCLUSION

The PRS313 can be used to refine individual CBC risks for BRCA1/2 heterozygotes of European ancestry, however the PRS313 needs to be considered in the context of a multifactorial risk model to evaluate whether it might influence clinical decision-making.

Efficacy and safety of first-line veliparib and carboplatin-paclitaxel in patients with HER2- advanced germline BRCA+ breast cancer: Subgroup analysis of a randomised clinical trial

BACKGROUND

Addition of veliparib to carboplatin-paclitaxel, with continuation of veliparib monotherapy if carboplatin-paclitaxel was discontinued, improved progression-free survival (PFS) in patients with germline BRCA-associated locally advanced/metastatic HER2- breast cancer and ≤2 lines of previous cytotoxic therapy for metastatic disease in BROCADE3. A pre-planned subgroup analysis evaluated efficacy and safety in patients without previous cytotoxic therapy for metastatic disease.

METHODS

Patients were randomised 2:1 to receive veliparib (120 mg orally BID) or placebo on days -2 to 5. Carboplatin (AUC 6) was administered on day 1, and paclitaxel (80 mg/m²) on days 1, 8 and 15 (21-day cycles). Patients discontinuing carboplatin-paclitaxel for reasons besides progression could continue veliparib/placebo monotherapy (300 mg BID, increasing to 400 mg BID if tolerated) until progression. The primary end-point was PFS assessed by investigator.

RESULTS

Of 509 patients in the intention-to-treat population (98.6% female; mean age 47, standard deviation 11), 413 (81%) had no previous cytotoxic therapy for metastatic disease (274, veliparib; 139, placebo). In the first-line subgroup, median PFS was 16.6 months (95% confidence interval [CI] 13.4-18.7) versus 13.1 months (95% CI 11.4-14.5) for the veliparib versus control groups (hazard ratio 0.70, 95% CI 0.54-0.89, P = .004). More patients were alive and progression-free at 2 years (36% versus 23.2%) and 3 years (27.9% versus 13.3%) in the veliparib versus control group. Adverse events unrelated to progression leading to study drug discontinuation occurred in 25 (9.1%) and 8 (5.8%) patients.

CONCLUSIONS

Veliparib with carboplatin-paclitaxel led to durable disease control among first-line patients, suggesting a benefit of this treatment approach in early lines.

CLINICAL TRIAL REGISTRATION

NCT02163694.

Uptake of cancer risk management strategies among women who undergo cascade genetic testing for breast cancer susceptibility genes

BACKGROUND

Uptake of cancer risk management based on inherited predispositions, which encompasses bilateral mastectomy (BLM), bilateral salpingo-oophorectomy (BSO), and intensified screening, is the primary motivation for cascade testing for hereditary breast and ovarian cancer (HBOC). However, long-term outcome data for cascade testers are lacking.

METHODS

Medical records were abstracted for all unaffected women with pathogenic variants in HBOC genes from 2 cancer hospitals (2013-2019) with at least 1 year of follow-up to compare the uptake of surgery and screening between cascade and noncascade testers.

RESULTS

Cascade testers (79.8%) were younger than noncascade testers (mean age, 37.6 vs 43.5 years; P = .002). Among women aged ≥40 years, 43% underwent BLM, and 71.6% underwent BSO, with no significant difference in uptake between cascade and noncascade testers. The mean time to BSO among cascade testers was shorter among women aged ≥40 years versus those aged <40 years (11.8 vs 31.9 months; P = .04); no such difference was observed among noncascade testers. Mammography and breast magnetic resonance imaging rates were low in the recorded 6 years for both groups after genetic counseling.

CONCLUSIONS

Management uptake among cascade testers is high with rates comparable to those for unaffected BRCA-positive women. A large proportion of women act on cascade test results, and this represents a novel report of utilization of cancer management strategies.

Author Correction: A case-only study to identify genetic modifiers of breast cancer risk for BRCA1/BRCA2 mutation carriers

A Correction to this paper has been published: https://doi.org/10.1038/s41467-021-23162-4

Influencers of the Decision to Undergo Contralateral Prophylactic Mastectomy among Women with Unilateral Breast Cancer

Simple Summary

In this survey study, we examined survey responses from 397 women with stage 0 to III unilateral breast cancer and found that partners, physicians, and the media were significant relative to the patient’s own influence in their decision to undergo a CPM. The findings of this study may inform policy by highlighting the need for educational aids, programs, or tools that help women with unilateral breast cancer make informed, evidence-based decisions regarding CPM efficacy.

Abstract

(1) Background: The relatively high rate of contralateral prophylactic mastectomy (CPM) among women with early stage unilateral breast cancer (BC) has raised concerns. We sought to assess the influence of partners, physicians, and the media on the decision of women with unilateral BC to undergo CPM and identify clinicopathological variables associated with the decision to undergo CPM. (2) Patients and Methods: Women with stage 0 to III unilateral BC who underwent CPM between January 2010 and December 2017. Patients were surveyed regarding factors influencing their self-determined decision to undergo CPM. Partner, physician, and media influence factors were modeled by logistic regressions with adjustments for a family history of breast cancer and pathological stage. (3) Results: 397 (29.6%) patients completed the survey and were included in the study. Partners, physicians, and the media significantly influenced patients’ decision to undergo CPM. The logistic regression models showed that, compared to self-determination alone, overall influence on the CPM decision was significantly higher for physicians (p = 0.0006) and significantly lower for partners and the media (p < 0.0001 for both). Fifty-nine percent of patients’ decisions were influenced by physicians, 28% were influenced by partners, and only 17% were influenced by the media. The model also showed that patients with a family history of BC had significantly higher odds of being influenced by a partner than did those without a family history of BC (p = 0.015). (4) Conclusions: Compared to self-determination, physicians had a greater influence and partners and the media had a lower influence on the decision of women with unilateral BC to undergo CPM. Strong family history was significantly associated with a patient’s decision to undergo CPM.

Targeting Replicative Stress and DNA Repair by Combining PARP and Wee1 Kinase Inhibitors Is Synergistic in Triple Negative Breast Cancers with Cyclin E or BRCA1 Alteration

Simple Summary

Triple-negative breast cancer (TNBC) is a subtype of invasive breast cancer with an aggressive phenotype that has decreased survival compared with other types of breast cancers, due in part to the lack of biomarker driven targeted therapies. Here, we show that breast cancer patients whose tumors show high levels of cyclin E expression have a higher prevalence of BRCA1/2 alterations and have the worst clinical outcomes. In vitro and in vivo studies revealed that combination therapies with poly (ADP-ribose) polymerase (PARP) and Wee1 kinase inhibitors in TNBC cells with either BRCA1 mutations or high levels of cyclin E results in synergistic cell death due to induction of replicative stress and downregulation of DNA repair. These studies suggest that by preselecting patients whose tumors have high cyclin E levels or harbor mutations in BRCA1, only those cases with the highest replicative stress properties will be subjected to combination treatment and likely result in synergistic activity of the two agents.

Abstract

The identification of biomarker-driven targeted therapies for patients with triple negative breast cancer (TNBC) remains a major clinical challenge, due to a lack of specific targets. Here, we show that cyclin E, a major regulator of G1 to S transition, is deregulated in TNBC and is associated with mutations in DNA repair genes (e.g., BRCA1/2). Breast cancers with high levels of cyclin E not only have a higher prevalence of BRCA1/2 mutations, but also are associated with the worst outcomes. Using several in vitro and in vivo model systems, we show that TNBCs that harbor either mutations in BRCA1/2 or overexpression of cyclin E are very sensitive to the growth inhibitory effects of AZD-1775 (Wee 1 kinase inhibitor) when used in combination with MK-4837 (PARP inhibitor). Combination treatment of TNBC cell lines with these two agents results in synergistic cell killing due to induction of replicative stress, downregulation of DNA repair and cytokinesis failure that results in increased apoptosis. These findings highlight the potential clinical application of using cyclin E and BRCA mutations as biomarkers to select only those patients with the highest replicative stress properties that may benefit from combination treatment with Wee 1 kinase and PARP inhibitors.

A case-only study to identify genetic modifiers of breast cancer risk for BRCA1/BRCA2 mutation carriers

Breast cancer (BC) risk for BRCA1 and BRCA2 mutation carriers varies by genetic and familial factors. About 50 common variants have been shown to modify BC risk for mutation carriers. All but three, were identified in general population studies. Other mutation carrier-specific susceptibility variants may exist but studies of mutation carriers have so far been underpowered. We conduct a novel case-only genome-wide association study comparing genotype frequencies between 60,212 general population BC cases and 13,007 cases with BRCA1 or BRCA2 mutations. We identify robust novel associations for 2 variants with BC for BRCA1 and 3 for BRCA2 mutation carriers, P < 10-8, at 5 loci, which are not associated with risk in the general population. They include rs60882887 at 11p11.2 where MADD, SP11 and EIF1, genes previously implicated in BC biology, are predicted as potential targets. These findings will contribute towards customising BC polygenic risk scores for BRCA1 and BRCA2 mutation carriers.

Abstract PS4-31: Characteristics of HER2/neu positive breast cancer among patients with and without germline BRCAmutations

Introduction: Breast cancer in BRCA 1/2 carriers is a well-characterized disease process, and its association with triple negative breast cancer has been extensively studied. In contrast, there is limited data on BRCA carriers and HER2/neu positive breast cancer, which identifies this topic as an area for further investigation. The BRCA protein plays an important role in DNA replication, whereas HER2/neu is a proto-oncogene that, when overexpressed, correlates with aggressive cancers. The relationship between these two mutations is poorly understood. There have been major strides with anti-HER2/neu therapies for HER2/neu positive disease and PARP inhibitors for BRCA germline positive patients, however there is a clinical knowledge gap in BRCA carriers who also have HER2/neu positive breast cancer. Further research into the characteristics of this population, treatment strategies, and outcomes is needed. More specifically, determining the utility of anti-HER2/neu therapies, PARP inhibitors, or the combination in this population could prove to have clinical utility. We aim to characterize the clinical characteristics, treatment strategies, and outcomes within this population.

Methods: Using a prospective research patient database at the UT MD Anderson Cancer Center 1038 patients were identified to have HER2/neu associated breast cancer who had undergone genetic counseling and testing for hereditary breast cancer syndromes between 1996 and 2019. This population was descriptively characterized to evaluate the prevalence of BRCA 1/2 positivity. Clinical and pathological characteristics as well as treatment, and recurrence were collected. Chi-square was used for statistical analysis. The Kaplan-Meier method was used to compare overall survival based on BRCA status.

Results: Amongst 1038 patients, germline BRCA mutation was detected in 49 (4.7%) of the patients. The median age at diagnosis for patients with BRCA mutations was significantly younger, 41.7 years (27-76), compared to 44.9 years (21-83) in the BRCA negative group (p= 0.0147). More patients were premenopausal in the BRCA positive group (p=0.027). Further characteristics are shown in Table 1. Overall survival was 71.6 months for the BRCA1 population, 81.3 months for the BRCA2 population, and 70.7 months for the BRCA negative population (p = 0.63). Recurrence free survival was 71 months for the BRCA1, 51.2 months for the BRCA2, and 59.6 months for the BRCA negative cohort (p = 0.4).

Conclusion: HER2/neu positive breast cancer patients with and without germline BRCA mutations have different clinical presentations. While we did not detect a survival difference due to small number of patients, this presents an opportunity to evaluate whether new treatment strategies, such as combining anti-HER2/neu therapies with PARP inhibitors can further improve outcomes for these patients.

Table 1:BRCA negativeBRCA positivep valuen%n%RaceASIAN666.724.10.0122BLACK979.8510.2HISPANIC16716.936.1NATIVE AMERICAN50.500.0OTHER111.148.2WHITE64365.03571.4Menopause Status at DxN/A40.400.00.0268POST17818.036.1PRE53454.03265.3Unknown27327.61428.6Age at Dxavg (range)44.9 (21-83)41.7 (27-76)0.0147Histology Typeductal93694.64591.80.3741lobular181.812.0mixed262.636.1other90.900.0StageI23523.81632.70.3293II46747.22040.8III28228.51224.5Unknown50.512.0Hormone Receptor StatusER and/or PR positive62663.33061.20.7271ER/PR negative35736.11938.8Unknown60.600.0Nuclear GradeI90.912.00.3474II22222.4714.3III69370.13673.5Unknown656.6510.2Ki67avg (range)40.5 (0-99)46 (10-90)0.1858Chemotypeadj32733.11632.70.2932neoadj56757.32551.0no chemo959.6816.3Herceptin Trxadj27027.31428.60.4093neoadj50651.22142.9none21121.31428.6unknown20.200.0Adj HormoneN44244.72449.00.5558Y54755.32551.0XRTN38038.42244.90.3637Y60961.62755.1989100.049100.0

Citation Format: Mihir A Shukla, Angelica Gutierrez Barrera, Stephen Karl Gruschkus, Rachel M Layman, Rashmi K Murthy, Banu K Arun. Characteristics of HER2/neu positive breast cancer among patients with and without germline BRCAmutations [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 PS4-31.

Abstract PS8-04: Clinical and pathological characteristics and screening outcome for secondary cancers in breast cancer patients with li-fraumeni syndrome attending the MD anderson li-fraumeni education and early detection program clinic

Background: Germline TP53 mutations predispose to early onset breast cancer (BC) and are associated with Li-Fraumeni syndrome (LFS) Published data on the clinical and pathological characteristics and screening outcome for secondary cancers among women with BC and TP53 mutations is limited. The UTMD Anderson's Li-Fraumeni Education and Early Detection (LEAD) program conducts comprehensive cancer screening for patients with LFS. Here we report characteristics and screening outcome of patients with BC and LFS who were referred to the LEAD program.

Methods: Patients with BC and LFS were identified from a prospective BC database between 2001 to 2018. Patients had genetic testing at The University of Texas MD Anderson Cancer Center (MDACC) Clinical Cancer Genetics (CCG) program and confirmed to have germline TP53 mutations. Data reviewed included clinical and pathological characteristics of their BC, the pattern of referral to the LEAD program, adherence to screening recommendation and rate of secondary cancer detection in the LEAD program.

Results: A total of 78 female patients with positive germline TP53 mutation and BC diagnosis were identified. The clinical and pathological characteristics of these patients are provided in table 1. Out of the 78 patients, 62 patients were referred and followed at the LEAD clinic. 50 were referred after BC diagnosis and 12 were referred to LEAD clinic before BC diagnosis. A total of 137 cancers were diagnosed in the total population. The cancers were further grouped into diagnosed before or after BC diagnosis. (table 2). 24 cancers were diagnosed in LEAD clinic including 12 breast cancers, 2 soft tissue tumors, 2 thyroid cancers, 2 acute myeloid leukemia, 1 brain tumor, 1 lung cancer, 1 pancreatic cancer, 1 melanoma, 1 parotid cancer and 1 Merkel cell cancer. Adherence to follow up and recommended screening in the first year was 77%, second year 75% and third year 65%. 6 patients, who were diagnosed with leukemia, had received adjuvant chemotherapy with anthracycline and/or cyclophosphamide-based therapy for breast cancer with median time from chemotherapy to leukemia diagnosis of 9 years (5-10yrs). 8 patients developed chest wall sarcoma in the same location of prior radiation therapy for breast cancer with median time from radiation therapy to chest wall sarcoma diagnosis of 7 years (3-11yrs).

Conclusion: Patients with LFS associated breast cancer are at significant increased risk to develop secondary cancers. Increased surveillance for secondary cancers in a dedicated program can increase adherence to screening, lead to early detection that could potentially lead to improved outcomes. Patient outcome of this cohort will be presented at the meeting.

Table 1: Clinical and Pathological Characteristics of Women with Breast cancer and LFSN(%)N(%)Median Age (Range)33 (20, 63)——Hormonal receptor/HER-2 status+/+22(31.4%)RaceAsian/Pacific islander7(9%)+/-27(38.6%)Black8(10.3%)-/+14(20%)Hispanic12(15.4%)-/-7(10%)White51(65.4%)Menopausal status at the time of BC diagnosis.Pre-menopausal(72%)Stage013(16.9%)Post-menopausal(28%)I21(27.3%)HistologyDCIS12(15.6%)II31(40.3%)IDC49(63.6%)III9(11.7%)ILC3(3.9%)IV3(3.9%)LCIS1(1.3%)Breast cancer diagnosisMRI4(5.2%)Mixed8(10.4%)Palpated lesion51(66.2%)Mucinous2(2.6%)Screening mammogram22(28.6%)Phyllodes2(2.6%)

Table 2: Cancer diagnosed in the total population N=78 grouped into before and after to BC diagnosisCancer diagnosed before BC diagnosisNCancer diagnosed after BC diagnosisNSoft tissue sarcoma13Soft tissue sarcoma18CNS1Lung2Thyroid3Thyroid3leukemia2Merkel cell1Adrenal2Leukemia6Uterus1CNS3Renal1pancreas1Melanoma1Parotid1

Citation Format: Aydah Al-Awadhi, Nour Abuhadra, Diane D Liu, Angelica M Gutierrez Barrera, Jessica Corredor, Louise C Strong, Banu K Arun. Clinical and pathological characteristics and screening outcome for secondary cancers in breast cancer patients with li-fraumeni syndrome attending the MD anderson li-fraumeni education and early detection program clinic [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 PS8-04.

Clinical practice guidelines for BRCA1 and BRCA2 genetic testing

BRCA1 and BRCA2 gene pathogenic variants account for most hereditary breast cancer and are increasingly used to determine eligibility for PARP inhibitor (PARPi) therapy of BRCA-related cancer. Because issues of BRCA testing in clinical practice now overlap with both preventive and therapeutic management, updated and comprehensive practice guidelines for BRCA genotyping are needed. The integrative recommendations for BRCA testing presented here aim to (1) identify individuals who may benefit from genetic counselling and risk-reducing strategies; (2) update germline and tumour-testing indications for PARPi-approved therapies; (3) provide testing recommendations for personalised management of early and metastatic breast cancer; and (4) address the issues of rapid process and tumour analysis. An international group of experts, including geneticists, medical and surgical oncologists, pathologists, ethicists and patient representatives, was commissioned by the French Society of Predictive and Personalised Medicine (SFMPP). The group followed a methodology based on specific formal guidelines development, including (1) evaluating the likelihood of BRCAm from a combined systematic review of the literature, risk assessment models and expert quotations, and (2) therapeutic values of BRCAm status for PARPi therapy in BRCA-related cancer and for management of early and advanced breast cancer. These international guidelines may help clinicians comprehensively update and standardise BRCA testing practices.

Polygenic risk scores and breast and epithelial ovarian cancer risks for carriers of BRCA1 and BRCA2 pathogenic variants

PURPOSE

We assessed the associations between population-based polygenic risk scores (PRS) for breast (BC) or epithelial ovarian cancer (EOC) with cancer risks for BRCA1 and BRCA2 pathogenic variant carriers.

METHODS

Retrospective cohort data on 18,935 BRCA1 and 12,339 BRCA2 female pathogenic variant carriers of European ancestry were available. Three versions of a 313 single-nucleotide polymorphism (SNP) BC PRS were evaluated based on whether they predict overall, estrogen receptor (ER)-negative, or ER-positive BC, and two PRS for overall or high-grade serous EOC. Associations were validated in a prospective cohort.

RESULTS

The ER-negative PRS showed the strongest association with BC risk for BRCA1 carriers (hazard ratio [HR] per standard deviation = 1.29 [95% CI 1.25-1.33], P = 3×10-72). For BRCA2, the strongest association was with overall BC PRS (HR = 1.31 [95% CI 1.27-1.36], P = 7×10-50). HR estimates decreased significantly with age and there was evidence for differences in associations by predicted variant effects on protein expression. The HR estimates were smaller than general population estimates. The high-grade serous PRS yielded the strongest associations with EOC risk for BRCA1 (HR = 1.32 [95% CI 1.25-1.40], P = 3×10-22) and BRCA2 (HR = 1.44 [95% CI 1.30-1.60], P = 4×10-12) carriers. The associations in the prospective cohort were similar.

CONCLUSION

Population-based PRS are strongly associated with BC and EOC risks for BRCA1/2 carriers and predict substantial absolute risk differences for women at PRS distribution extremes.

Biomarker Modulation Study of Celecoxib for Chemoprevention in Women at Increased Risk for Breast Cancer: A Phase II Pilot Study

In preclinical studies, celecoxib has been associated with reduced risk of breast cancer. In this study, the aim was to assess the biomodulatory effect of celecoxib on blood and benign breast tissue biomarkers in women at increased risk for breast cancer. Women at increased risk for breast cancer [5-year Gail risk score of >1.67%, history of atypical hyperplasia, lobular carcinoma in situ, or previous estrogen receptor (ER)-negative breast cancer] were treated with celecoxib at 400 mg orally twice daily for 6 months. Participants underwent random periareolar fine needle aspiration and blood draw at baseline and at 6 months for analysis of biomarkers: serum levels of insulin-like growth factor 1 (IGF-1), IGF-binding protein 1 (IGFBP-1), and IGFBP-3; tissue expression of Ki-67 and ER; as well as cytology. Forty-nine patients were eligible for analysis. Median IGFBP-1 levels increased significantly from 6.05 ng/mL at baseline to 6.93 ng/mL at 6 months (P = 0.04), and median IGFBP-3 levels decreased significantly from 3,593 ng/mL to 3,420 ng/mL (P = 0.01). We also detected favorable changes in cytology of 52% of tested sites after 6 months of celecoxib therapy. No changes in tissue Ki-67 and ER expression levels were observed. No grade 3 or 4 toxicity was recorded. Celecoxib was well tolerated and induced favorable changes in serum biomarkers as well as cytology in this pilot phase II trial. A phase IIb placebo-controlled study with celecoxib could be considered for women at increased risk for breast cancer.

Contralateral Risk-Reducing Mastectomy in Breast Cancer Patients Who Undergo Multigene Panel Testing

BACKGROUND

An increasing number of breast cancer patients are undergoing expanded genetic testing and are being identified as germline mutation carriers. We sought to determine rates of contralateral risk-reducing mastectomy (CRRM) in patients with various germline mutations.

PATIENTS AND METHODS

All women ≥ 18 years of age with unilateral breast cancer who underwent multigene panel testing between January 1, 2014 and August 1, 2019 at our academic institution were identified. Demographic, tumor, and treatment variables were identified from the medical record. Multivariable analyses were performed to compare factors associated with performance of CRRM.

RESULTS

We identified 1613 patients, of whom 28.1% had a pathogenic variant and 40.1% had variants of uncertain significance (VUS). Overall, 420 patients (26.0%) underwent a CRRM. On multivariable analysis, factors associated with CRRM included age < 50 years (OR 3.8, 95% CI 3.0, 5.0), race (OR 0.5, 95% CI 0.3, 0.7 and OR 0.4, 95% CI 0.2, 0.7 for Black and Asian women, respectively, versus White women), and the presence of any germline mutation or VUS (OR 13.2, 95% CI 8.7, 20.2 for BRCA1/2; OR 3.9, 95% CI 2.7, 5.8 for non-BRCA germline mutation; and OR 1.8, 95% CI 1.3, 2.6 for VUS).

CONCLUSIONS

In breast cancer patients who undergo multigene panel testing, a sizeable number of women with pathogenic non-BRCA germline findings are opting for CRRM. Given that the risk of contralateral breast cancer in women with most pathogenic mutations other than BRCA1/2 remains poorly characterized, these data have implications for risk counseling and for ascertaining the true risks of contralateral breast cancer in this population.