Racial disparities in breast cancer risk factors and risk management

Racial disparities in breast cancer outcomes are well described across the spectrum of screening, diagnosis, treatment, and survivorship. Breast cancer mortality is markedly elevated for Non-Hispanic Black women compared with other racial and ethnic groups, with multifactorial causes. Here, we aim to reduce this burden by identifying disparities in breast cancer risk factors, risk assessment, and risk management before breast cancer is diagnosed. We describe a reproductive profile and modifiable risk factors specific to the development of triple-negative breast cancer. We also propose that screening strategies should be both risk- and race-based, given the prevalence of early-onset triple-negative breast cancer in young Black women. We emphasize the importance of early risk assessment and identification of patients at hereditary and familial risk and discuss indications for a high-risk referral. We discuss the subtleties following genetic testing and highlight "uncertain" genetic testing results and risk estimation challenges in women who test negative. We trace aspects of the obesity epidemic in the Black community to infant feeding patterns and emphasize healthy eating and activity. Finally, we discuss building an environment of trust to foster adherence to recommendations, follow-up care, and participation in clinical trials. Addressing relevant social determinants of health; educating patients and clinicians on factors impacting disparities in outcomes; and encouraging participation in targeted, culturally sensitive research are essential to best serve all communities.

Avoiding lead-time bias by estimating stage-specific proportions of cancer and non-cancer deaths

PURPOSE

Understanding how stage at cancer diagnosis influences cause of death, an endpoint that is not susceptible to lead-time bias, can inform population-level outcomes of cancer screening.

METHODS

Using data from 17 US Surveillance, Epidemiology, and End Results registries for 1,154,515 persons aged 50-84 years at cancer diagnosis in 2006-2010, we evaluated proportional causes of death by cancer type and uniformly classified stage, following or extrapolating all patients until death through 2020.

RESULTS

Most cancer patients diagnosed at stages I-II did not go on to die from their index cancer, whereas most patients diagnosed at stage IV did. For patients diagnosed with any cancer at stages I-II, an estimated 26% of deaths were due to the index cancer, 63% due to non-cancer causes, and 12% due to a subsequent primary (non-index) cancer. In contrast, for patients diagnosed with any stage IV cancer, 85% of deaths were attributed to the index cancer, with 13% non-cancer and 2% non-index-cancer deaths. Index cancer mortality from stages I-II cancer was proportionally lowest for thyroid, melanoma, uterus, prostate, and breast, and highest for pancreas, liver, esophagus, lung, and stomach.

CONCLUSION

Across all cancer types, the percentage of patients who went on to die from their cancer was over three times greater when the cancer was diagnosed at stage IV than stages I-II. As mortality patterns are not influenced by lead-time bias, these data suggest that earlier detection is likely to improve outcomes across cancer types, including those currently unscreened.

Collaborative Modeling to Compare Different Breast Cancer Screening Strategies: A Decision Analysis for the US Preventive Services Task Force

Importance

The effects of breast cancer incidence changes and advances in screening and treatment on outcomes of different screening strategies are not well known.

Objective

To estimate outcomes of various mammography screening strategies.

Design, Setting, and Population

Comparison of outcomes using 6 Cancer Intervention and Surveillance Modeling Network (CISNET) models and national data on breast cancer incidence, mammography performance, treatment effects, and other-cause mortality in US women without previous cancer diagnoses.

Exposures

Thirty-six screening strategies with varying start ages (40, 45, 50 years) and stop ages (74, 79 years) with digital mammography or digital breast tomosynthesis (DBT) annually, biennially, or a combination of intervals. Strategies were evaluated for all women and for Black women, assuming 100% screening adherence and "real-world" treatment.

Main Outcomes and Measures

Estimated lifetime benefits (breast cancer deaths averted, percent reduction in breast cancer mortality, life-years gained), harms (false-positive recalls, benign biopsies, overdiagnosis), and number of mammograms per 1000 women.

Results

Biennial screening with DBT starting at age 40, 45, or 50 years until age 74 years averted a median of 8.2, 7.5, or 6.7 breast cancer deaths per 1000 women screened, respectively, vs no screening. Biennial DBT screening at age 40 to 74 years (vs no screening) was associated with a 30.0% breast cancer mortality reduction, 1376 false-positive recalls, and 14 overdiagnosed cases per 1000 women screened. Digital mammography screening benefits were similar to those for DBT but had more false-positive recalls. Annual screening increased benefits but resulted in more false-positive recalls and overdiagnosed cases. Benefit-to-harm ratios of continuing screening until age 79 years were similar or superior to stopping at age 74. In all strategies, women with higher-than-average breast cancer risk, higher breast density, and lower comorbidity level experienced greater screening benefits than other groups. Annual screening of Black women from age 40 to 49 years with biennial screening thereafter reduced breast cancer mortality disparities while maintaining similar benefit-to-harm trade-offs as for all women.

Conclusions

This modeling analysis suggests that biennial mammography screening starting at age 40 years reduces breast cancer mortality and increases life-years gained per mammogram. More intensive screening for women with greater risk of breast cancer diagnosis or death can maintain similar benefit-to-harm trade-offs and reduce mortality disparities.

Incidence of Nonkeratinocyte Skin Cancer After Breast Cancer Radiation Therapy

Importance

Previous studies have suggested that radiation therapy may contribute to an increased risk of subsequent nonkeratinocyte (ie, not squamous and basal cell) skin cancers.

Objective

To test the hypothesis that radiation therapy for breast cancer increases the risk of subsequent nonkeratinocyte skin cancers, particularly when these cancers are localized to the skin of the breast or trunk.

Design, Setting, and Participants

This population-based cohort study used longitudinal data from the Surveillance, Epidemiology, and End Results (SEER) Program for January 1, 2000, to December 31, 2019. The SEER database includes population-based cohort data from 17 registries. Patients with newly diagnosed breast cancer were identified and were evaluated for subsequent nonkeratinocyte skin cancer development. Data analysis was performed from January to August 2023.

Exposures

Radiation therapy, chemotherapy, or surgery for breast cancer.

Main Outcomes and Measures

The primary outcomes were standardized incidence ratios (SIRs) for subsequent nonkeratinocyte skin cancer development from 2000 to 2019 based on treatment type (radiation therapy, chemotherapy, or surgery), skin cancer site on the body, and skin cancer subtype.

Results

Among the 875 880 patients with newly diagnosed breast cancer included in this study, 99.3% were women, 51.6% were aged older than 60 years, and 50.3% received radiation therapy. A total of 11.2% patients identified as Hispanic, 10.1% identified as non-Hispanic Black, and 69.5% identified as non-Hispanic White. From 2000 to 2019, there were 3839 patients with nonkeratinocyte skin cancer, including melanoma (3419 [89.1%]), Merkel cell carcinoma (121 [3.2%]), hemangiosarcoma (104 [2.7%]), and 32 other nonkeratinocyte skin cancers (195 [5.1%]), documented to occur after breast cancer treatment. The risk of nonkeratinocyte skin cancer diagnosis after breast cancer treatment with radiation was 57% higher (SIR, 1.57 [95% CI, 1.45-1.7]) than that of the general population when considering the most relevant site: the skin of the breast or trunk. When risk at this site was stratified by skin cancer subtype, the SIRs for melanoma and hemangiosarcoma were both statistically significant at 1.37 (95% CI, 1.25-1.49) and 27.11 (95% CI, 21.6-33.61), respectively. Receipt of radiation therapy was associated with a greater risk of nonkeratinocyte skin cancer compared with chemotherapy and surgical interventions.

Conclusions and Relevance

In this study of patients with breast cancer, an increased risk of melanoma and hemangiosarcoma after breast cancer treatment with radiation therapy was observed. Although occurrences of nonkeratinocyte skin cancers are rare, physicians should be aware of this elevated risk to help inform follow-up care.

Tumor-infiltrating lymphocytes and breast cancer mortality in racially and ethnically diverse participants of the Northern California Breast Cancer Family Registry

Stromal tumor-infiltrating lymphocyte (sTIL) enrichment in pretreatment breast tumors has been associated with superior response to neoadjuvant treatment and survival. In a population-based cohort, we studied sTIL-survival associations by race and ethnicity. We assessed associations of continuous sTIL scores and sTIL-enriched breast cancers (defined as percent lymphocytic infiltration of tumor stroma or cell nests at cutoffs of 30%, 50%, and 70%) with clinical and epidemiologic characteristics and conducted multivariable survival analyses. Although we identified no difference in sTIL score by race and ethnicity, higher continuous sTIL score was associated with lower breast cancer-specific mortality only among non-Hispanic White and Asian American but not African American and Hispanic women. This finding suggests that complex factors influence treatment response and survival, given that sTIL enrichment was not associated with a survival advantage among women from minoritized groups, who more often experience health disparities. Further study of patient selection for sTIL-guided treatment strategies is warranted.

Germline Testing in Patients With Breast Cancer: ASCO-Society of Surgical Oncology Guideline

PURPOSE

To develop recommendations for germline mutation testing for patients with breast cancer.

METHODS

An ASCO-Society of Surgical Oncology (SSO) panel convened to develop recommendations based on a systematic review and formal consensus process.

RESULTS

Forty-seven articles met eligibility criteria for the germline mutation testing recommendations; 18 for the genetic counseling recommendations.

RECOMMENDATIONS

BRCA1/2 mutation testing should be offered to all newly diagnosed patients with breast cancer ≤65 years and select patients >65 years based on personal history, family history, ancestry, or eligibility for poly(ADP-ribose) polymerase (PARP) inhibitor therapy. All patients with recurrent breast cancer who are candidates for PARP inhibitor therapy should be offered BRCA1/2 testing, regardless of family history. BRCA1/2 testing should be offered to women who develop a second primary cancer in the ipsilateral or contralateral breast. For patients with prior history of breast cancer and without active disease, testing should be offered to patients diagnosed ≤65 years and selectively in patients diagnosed after 65 years, if it will inform personal and family risk. Testing for high-penetrance cancer susceptibility genes beyond BRCA1/2 should be offered to those with supportive family histories; testing for moderate-penetrance genes may be offered if necessary to inform personal and family cancer risk. Patients should be provided enough pretest information for informed consent; those with pathogenic variants should receive individualized post-test counseling. Variants of uncertain significance should not impact management, and patients with such variants should be followed for reclassification. Referral to providers experienced in clinical cancer genetics may help facilitate patient selection and interpretation of expanded testing, and provide counseling of individuals without pathogenic germline variants but with significant family history.Additional information is available at www.asco.org/breast-cancer-guidelines.

Cascade testing for hereditary cancer: comprehensive multigene panels identify unexpected actionable findings in relatives

Current guidelines recommend single variant testing in relatives of patients with known pathogenic or likely pathogenic germline variants in cancer predisposition genes. This approach may preclude the use of risk-reducing strategies in family members who have pathogenic or likely pathogenic germline variants in other cancer predisposition genes. Cascade testing using multigene panels was performed in 3696 relatives of 7433 probands. Unexpected pathogenic or likely pathogenic germline variants were identified in 230 (6.2%) relatives, including 144 who were negative for the familial pathogenic or likely pathogenic variant but positive for a pathogenic or likely pathogenic variant in a different gene than the proband and 74 who tested positive for the familial pathogenic or likely pathogenic variant and had an additional pathogenic or likely pathogenic variant in a different gene than the proband. Of the relatives with unexpected pathogenic or likely pathogenic germline variants, 36.3% would have qualified for different or additional cancer screening recommendations. Limiting cascade testing to only the familial pathogenic or likely pathogenic variant would have resulted in missed, actionable findings for a subset of relatives.

Recurrent BRCA2 exon 3 deletion in Assyrian families

We identified six patients from five families with a recurrent mutation: NM_000059.3 (BRCA2) exon 3 deletion. All families self-identified as Assyrian. Assyrians are an ethnoreligious population of ancient Mesopotamia, now mostly living in modern day Iraq, Syria, Turkey and Iran. They are historically a socially isolated population with intermarriage within their community, living as a religious and language minority in mostly Muslim countries. The probands of each family presented with a classic BRCA2-associated cancer including early-onset breast cancer, epithelial serous ovarian cancer, male breast cancer and/or high-grade prostate cancer, and family history that was also significant for BRCA2-associated cancer. BRCA2 exon 3 deletion is classified as pathogenic and has been previously described in the literature, but it has not been described as a founder mutation in a particular population. We characterise this recurrent BRCA2 pathogenic variant in five Assyrian families in a single centre cohort.

Analysis of Breast Cancer Mortality in the US-1975 to 2019

Importance

Breast cancer mortality in the US declined between 1975 and 2019. The association of changes in metastatic breast cancer treatment with improved breast cancer mortality is unclear.

Objective

To simulate the relative associations of breast cancer screening, treatment of stage I to III breast cancer, and treatment of metastatic breast cancer with improved breast cancer mortality.

Design, Setting, and Participants

Using aggregated observational and clinical trial data on the dissemination and effects of screening and treatment, 4 Cancer Intervention and Surveillance Modeling Network (CISNET) models simulated US breast cancer mortality rates. Death due to breast cancer, overall and by estrogen receptor and ERBB2 (formerly HER2) status, among women aged 30 to 79 years in the US from 1975 to 2019 was simulated.

Exposures

Screening mammography, treatment of stage I to III breast cancer, and treatment of metastatic breast cancer.

Main Outcomes and Measures

Model-estimated age-adjusted breast cancer mortality rate associated with screening, stage I to III treatment, and metastatic treatment relative to the absence of these exposures was assessed, as was model-estimated median survival after breast cancer metastatic recurrence.

Results

The breast cancer mortality rate in the US (age adjusted) was 48/100 000 women in 1975 and 27/100 000 women in 2019. In 2019, the combination of screening, stage I to III treatment, and metastatic treatment was associated with a 58% reduction (model range, 55%-61%) in breast cancer mortality. Of this reduction, 29% (model range, 19%-33%) was associated with treatment of metastatic breast cancer, 47% (model range, 35%-60%) with treatment of stage I to III breast cancer, and 25% (model range, 21%-33%) with mammography screening. Based on simulations, the greatest change in survival after metastatic recurrence occurred between 2000 and 2019, from 1.9 years (model range, 1.0-2.7 years) to 3.2 years (model range, 2.0-4.9 years). Median survival for estrogen receptor (ER)-positive/ERBB2-positive breast cancer improved by 2.5 years (model range, 2.0-3.4 years), whereas median survival for ER-/ERBB2- breast cancer improved by 0.5 years (model range, 0.3-0.8 years).

Conclusions and Relevance

According to 4 simulation models, breast cancer screening and treatment in 2019 were associated with a 58% reduction in US breast cancer mortality compared with interventions in 1975. Simulations suggested that treatment for stage I to III breast cancer was associated with approximately 47% of the mortality reduction, whereas treatment for metastatic breast cancer was associated with 29% of the reduction and screening with 25% of the reduction.

Evaluation of European-based polygenic risk score for breast cancer in Ashkenazi Jewish women in Israel

BACKGROUND

Polygenic risk score (PRS), calculated based on genome-wide association studies (GWASs), can improve breast cancer (BC) risk assessment. To date, most BC GWASs have been performed in individuals of European (EUR) ancestry, and the generalisation of EUR-based PRS to other populations is a major challenge. In this study, we examined the performance of EUR-based BC PRS models in Ashkenazi Jewish (AJ) women.

METHODS

We generated PRSs based on data on EUR women from the Breast Cancer Association Consortium (BCAC). We tested the performance of the PRSs in a cohort of 2161 AJ women from Israel (1437 cases and 724 controls) from BCAC (BCAC cohort from Israel (BCAC-IL)). In addition, we tested the performance of these EUR-based BC PRSs, as well as the established 313-SNP EUR BC PRS, in an independent cohort of 181 AJ women from Hadassah Medical Center (HMC) in Israel.

RESULTS

In the BCAC-IL cohort, the highest OR per 1 SD was 1.56 (±0.09). The OR for AJ women at the top 10% of the PRS distribution compared with the middle quintile was 2.10 (±0.24). In the HMC cohort, the OR per 1 SD of the EUR-based PRS that performed best in the BCAC-IL cohort was 1.58±0.27. The OR per 1 SD of the commonly used 313-SNP BC PRS was 1.64 (±0.28).

CONCLUSIONS

Extant EUR GWAS data can be used for generating PRSs that identify AJ women with markedly elevated risk of BC and therefore hold promise for improving BC risk assessment in AJ women.

Care after premenopausal risk-reducing salpingo-oophorectomy in high-risk women: Scoping review and international consensus recommendations

Women at high inherited risk of ovarian cancer are offered risk-reducing salpingo-oophorectomy (RRSO) from age 35 to 45 years. Although potentially life-saving, RRSO may induce symptoms that negatively affect quality of life and impair long-term health. Clinical care following RRSO is often suboptimal. This scoping review describes how RRSO affects short- and long-term health and provides evidence-based international consensus recommendations for care from preoperative counselling to long-term disease prevention. This includes the efficacy and safety of hormonal and non-hormonal treatments for vasomotor symptoms, sleep disturbance and sexual dysfunction and effective approaches to prevent bone and cardiovascular disease.

NCCN Guidelines® Insights: Genetic/Familial High-Risk Assessment: Breast, Ovarian, and Pancreatic, Version 2.2024

The NCCN Guidelines for Genetic/Familial High-Risk Assessment: Breast, Ovarian, and Pancreatic focus primarily on assessment of pathogenic/likely pathogenic (P/LP) variants associated with increased risk of breast, ovarian, pancreatic, and prostate cancer, including BRCA1, BRCA2, CDH1, PALB2, PTEN, and TP53, and recommended approaches to genetic counseling/testing and care strategies in individuals with these P/LP variants. These NCCN Guidelines Insights summarize important updates regarding: (1) a new section for transgender, nonbinary and gender diverse people who have a hereditary predisposition to cancer focused on risk reduction strategies for ovarian cancer, uterine cancer, prostate cancer, and breast cancer; and (2) testing criteria and management associated with TP53 P/LP variants and Li-Fraumeni syndrome.

Overall Survival Among Patients With De Novo Stage IV Metastatic and Distant Metastatic Recurrent Non-Small Cell Lung Cancer

Importance

Despite recent breakthroughs in therapy, advanced lung cancer still poses a therapeutic challenge. The survival profile of patients with metastatic lung cancer remains poorly understood by metastatic disease type (ie, de novo stage IV vs distant recurrence).

Objective

To evaluate the association of metastatic disease type on overall survival (OS) among patients with non-small cell lung cancer (NSCLC) and to identify potential mechanisms underlying any survival difference.

Design, Setting, and Participants

Cohort study of a national US population based at a tertiary referral center in the San Francisco Bay Area using participant data from the National Lung Screening Trial (NLST) who were enrolled between 2002 and 2004 and followed up for up to 7 years as the primary cohort and patient data from Stanford Healthcare (SHC) for diagnoses between 2009 and 2019 and followed up for up to 13 years as the validation cohort. Participants from NLST with de novo metastatic or distant recurrent NSCLC diagnoses were included. Data were analyzed from January 2021 to March 2023.

Exposures

De novo stage IV vs distant recurrent metastatic disease.

Main Outcomes and Measures

OS after diagnosis of metastatic disease.

Results

The NLST and SHC cohort consisted of 660 and 180 participants, respectively (411 men [62.3%] vs 109 men [60.6%], 602 White participants [91.2%] vs 111 White participants [61.7%], and mean [SD] age of 66.8 [5.5] vs 71.4 [7.9] years at metastasis, respectively). Patients with distant recurrence showed significantly better OS than patients with de novo metastasis (adjusted hazard ratio [aHR], 0.72; 95% CI, 0.60-0.87; P < .001) in NLST, which was replicated in SHC (aHR, 0.64; 95% CI, 0.43-0.96; P = .03). In SHC, patients with de novo metastasis more frequently progressed to the bone (63 patients with de novo metastasis [52.5%] vs 19 patients with distant recurrence [31.7%]) or pleura (40 patients with de novo metastasis [33.3%] vs 8 patients with distant recurrence [13.3%]) than patients with distant recurrence and were primarily detected through symptoms (102 patients [85.0%]) as compared with posttreatment surveillance (47 patients [78.3%]) in the latter. The main finding remained consistent after further adjusting for metastasis sites and detection methods.

Conclusions and Relevance

In this cohort study, patients with distant recurrent NSCLC had significantly better OS than those with de novo disease, and the latter group was associated with characteristics that may affect overall survival. This finding can help inform future clinical trial designs to ensure a balance for baseline patient characteristics.

Endometrial Cancer Risk Among Germline BRCA1/2 Pathogenic Variant Carriers: Review of Our Current Understanding and Next Steps

PURPOSE

To review the literature exploring endometrial cancer (EC) risk among surgical candidates with germline BRCA1/2 pathogenic variants (PVs) to guide decisions around risk-reducing (rr) hysterectomy in this population.

DESIGN

A comprehensive review was conducted of the current literature that influences clinical practice and informs expert consensus. We present our understanding of EC risk among BRCA1/2 PV carriers, the risk-modifying factors specific to this patient population, and the available research technology that may guide clinical practice in the future. Limitations of the existing literature are outlined.

RESULTS

Patients with BRCA1/2 PVs, those with a personal history of tamoxifen use, those who desire long-term hormone replacement therapy, and/or have an elevated BMI are at higher risk of EC, primarily endometrioid EC and/or uterine papillary serous carcinoma, and may benefit from rr-hysterectomy. Although prescriptive clinical guidelines specific to BRCA1/2 PV carriers could inform decisions around rr-hysterectomy, limitations of the current literature prevent more definitive guidance at this time. A large population-based study of a contemporary cohort of BRCA1/2 PV carriers with lifetime follow-up compared with cancer-gene negative controls would advance this topic and facilitate care decisions.

CONCLUSION

This review validates a potential role for rr-hysterectomy to address EC risk among surgical candidates with BRCA1/2 PVs. Evidence-based clinical guidelines for rr-hysterectomy in BRCA1/2 PV carriers are essential to ensure equitable access to this preventive measure, supporting insurance coverage for patients with either BRCA1 or BRCA2 PVs to pursue rr-hysterectomy. Overall, this review highlights the complexity of EC risk in BRCA1/2 PV carriers and offers a comprehensive framework to shared decision making to inform rr-hysterectomy for BRCA1/2 PV carriers.

A genome-wide gene-environment interaction study of breast cancer risk for women of European ancestry

BACKGROUND

Genome-wide studies of gene-environment interactions (G×E) may identify variants associated with disease risk in conjunction with lifestyle/environmental exposures. We conducted a genome-wide G×E analysis of ~ 7.6 million common variants and seven lifestyle/environmental risk factors for breast cancer risk overall and for estrogen receptor positive (ER +) breast cancer.

METHODS

Analyses were conducted using 72,285 breast cancer cases and 80,354 controls of European ancestry from the Breast Cancer Association Consortium. Gene-environment interactions were evaluated using standard unconditional logistic regression models and likelihood ratio tests for breast cancer risk overall and for ER + breast cancer. Bayesian False Discovery Probability was employed to assess the noteworthiness of each SNP-risk factor pairs.

RESULTS

Assuming a 1 × 10-5 prior probability of a true association for each SNP-risk factor pairs and a Bayesian False Discovery Probability < 15%, we identified two independent SNP-risk factor pairs: rs80018847(9p13)-LINGO2 and adult height in association with overall breast cancer risk (ORint = 0.94, 95% CI 0.92-0.96), and rs4770552(13q12)-SPATA13 and age at menarche for ER + breast cancer risk (ORint = 0.91, 95% CI 0.88-0.94).

CONCLUSIONS

Overall, the contribution of G×E interactions to the heritability of breast cancer is very small. At the population level, multiplicative G×E interactions do not make an important contribution to risk prediction in breast cancer.

Association of the CHEK2 c.1100delC variant, radiotherapy, and systemic treatment with contralateral breast cancer risk and breast cancer-specific survival

BACKGROUND

Breast cancer (BC) patients with a germline CHEK2 c.1100delC variant have an increased risk of contralateral BC (CBC) and worse BC-specific survival (BCSS) compared to non-carriers.

AIM

To assessed the associations of CHEK2 c.1100delC, radiotherapy, and systemic treatment with CBC risk and BCSS.

METHODS

Analyses were based on 82,701 women diagnosed with a first primary invasive BC including 963 CHEK2 c.1100delC carriers; median follow-up was 9.1 years. Differential associations with treatment by CHEK2 c.1100delC status were tested by including interaction terms in a multivariable Cox regression model. A multi-state model was used for further insight into the relation between CHEK2 c.1100delC status, treatment, CBC risk and death.

RESULTS

There was no evidence for differential associations of therapy with CBC risk by CHEK2 c.1100delC status. The strongest association with reduced CBC risk was observed for the combination of chemotherapy and endocrine therapy [HR (95% CI): 0.66 (0.55-0.78)]. No association was observed with radiotherapy. Results from the multi-state model showed shorter BCSS for CHEK2 c.1100delC carriers versus non-carriers also after accounting for CBC occurrence [HR (95% CI): 1.30 (1.09-1.56)].

CONCLUSION

Systemic therapy was associated with reduced CBC risk irrespective of CHEK2 c.1100delC status. Moreover, CHEK2 c.1100delC carriers had shorter BCSS, which appears not to be fully explained by their CBC risk.

Germline Genetic Testing After Cancer Diagnosis

Importance

Germline genetic testing is recommended by practice guidelines for patients diagnosed with cancer to enable genetically targeted treatment and identify relatives who may benefit from personalized cancer screening and prevention.

Objective

To describe the prevalence of germline genetic testing among patients diagnosed with cancer in California and Georgia between 2013 and 2019.

Design, Setting, and Participants

Observational study including patients aged 20 years or older who had been diagnosed with any type of cancer between January 1, 2013, and March 31, 2019, that was reported to statewide Surveillance, Epidemiology, and End Results registries in California and Georgia. These patients were linked to genetic testing results from 4 laboratories that performed most germline testing for California and Georgia.

Main Outcomes and Measures

The primary outcome was germline genetic testing within 2 years of a cancer diagnosis. Testing trends were analyzed with logistic regression modeling. The results of sequencing each gene, including variants associated with increased cancer risk (pathogenic results) and variants whose cancer risk association was unknown (uncertain results), were evaluated. The genes were categorized according to their primary cancer association, including breast or ovarian, gastrointestinal, and other, and whether practice guidelines recommended germline testing.

Results

Among 1 369 602 patients diagnosed with cancer between 2013 and 2019 in California and Georgia, 93 052 (6.8%) underwent germline testing through March 31, 2021. The proportion of patients tested varied by cancer type: male breast (50%), ovarian (38.6%), female breast (26%), multiple (7.5%), endometrial (6.4%), pancreatic (5.6%), colorectal (5.6%), prostate (1.1%), and lung (0.3%). In a logistic regression model, compared with the 31% (95% CI, 30%-31%) of non-Hispanic White patients with male breast cancer, female breast cancer, or ovarian cancer who underwent testing, patients of other races and ethnicities underwent testing less often: 22% (95% CI, 21%-22%) of Asian patients, 25% (95% CI, 24%-25%) of Black patients, and 23% (95% CI, 23%-23%) of Hispanic patients (P < .001 using the χ2 test). Of all pathogenic results, 67.5% to 94.9% of variants were identified in genes for which practice guidelines recommend testing and 68.3% to 83.8% of variants were identified in genes associated with the diagnosed cancer type.

Conclusions and Relevance

Among patients diagnosed with cancer in California and Georgia between 2013 and 2019, only 6.8% underwent germline genetic testing. Compared with non-Hispanic White patients, rates of testing were lower among Asian, Black, and Hispanic patients.

Clinical implications of conflicting variant interpretations in the cancer genetics clinic

PURPOSE

The aim of this study was to describe the clinical impact of commercial laboratories issuing conflicting classifications of genetic variants.

METHODS

Results from 2000 patients undergoing a multigene hereditary cancer panel by a single laboratory were analyzed. Clinically significant discrepancies between the laboratory-provided test reports and other major commercial laboratories were identified, including differences between pathogenic/likely pathogenic and variant of uncertain significance (VUS) classifications, via review of ClinVar archives. For patients carrying a VUS, clinical documentation was assessed for evidence of provider awareness of the conflict.

RESULTS

Fifty of 975 (5.1%) patients with non-negative results carried a variant with a clinically significant conflict, 19 with a pathogenic/likely pathogenic variant reported in APC or MUTYH, and 31 with a VUS reported in CDKN2A, CHEK2, MLH1, MSH2, MUTYH, RAD51C, or TP53. Only 10 of 28 (36%) patients with a VUS with a clinically significant conflict had a documented discussion by a provider about the conflict. Discrepant counseling strategies were used for different patients with the same variant. Among patients with a CDKN2A variant or a monoallelic MUTYH variant, providers were significantly more likely to make recommendations based on the laboratory-reported classification.

CONCLUSION

Our findings highlight the frequency of variant interpretation discrepancies and importance of clinician awareness. Guidance is needed on managing patients with discrepant variants to support accurate risk assessment.

Disparity in Breast Cancer Care: Current State of Access to Screening, Genetic Testing, Oncofertility, and Reconstruction

Breast cancer is the most common cancer diagnosed in women, accounting for an estimated 30% of all new cancer diagnoses in women in 2022. Advances in breast cancer treatment have reduced the mortality rate over the past 25 years by up to 34% but not all groups have benefitted equally from these improvements. These disparities span the continuum of care from screening to the receipt of guideline-concordant therapy and survivorship. At the 2022 American College of Surgeons Clinical Congress, a panel session was dedicated to educating and discussing methods of addressing these disparities in a coordinated manner. While there are multilevel solutions to address these disparities, this article focuses on screening, genetic testing, reconstruction, and oncofertility.

Cascade Genetic Risk Education and Testing in Families With Hereditary Cancer Syndromes: A Pilot Study

PURPOSE

Cascade genetic risk evaluation in families with hereditary cancer can reduce the burden of disease but the rate of germline genetic testing in relatives of patients at risk is low.

METHODS

We identified all 277 women diagnosed with breast cancer in Georgia in 2017 who linked to a clinically actionable germline pathogenic variant through a Surveillance, Epidemiology, and End Results registry-variant linkage initiative. We surveyed them, and then invited eligible respondents to an online platform hosted by a navigator that offered cancer genetic risk education and germline genetic testing to untested relatives. We randomly assigned patient-family clusters at the time of the patient enrollment offer to free versus $50 (USD) test cost. Patients invited relatives to join the study through personalized e-mail. Enrolled relatives received online cancer genetic education and the opportunity to order clinical germline genetic testing through the platform. The primary outcome was the number of relatives who ordered genetic testing.

RESULTS

One hundred twenty-five of 277 patients completed surveys (45.2%). Most respondents were eligible for the trial offer (113 of 125; 90.4%). In the free testing arm, 20 of 56 eligible patients participated (35.7% of eligible respondents) and they invited 28 relatives: 12 relatives enrolled and 10 ordered testing. In the $50 (USD) arm, 16 of 57 eligible patients participated (28.1%) and they invited 38 relatives: 18 relatives enrolled and 17 ordered testing.

CONCLUSION

Cascade genetic testing in families with hereditary cancer syndromes accrued through a population-based cancer registry can be achieved through an online platform that offers genetic risk education and low-cost testing to relatives. A modest charge did not appear to influence the percentage of participating patients, numbers of participating relatives, and numbers of relatives who received genetic testing.

Changes in Breast Cancer Risk and Risk Factor Profiles among U.S.-Born and Immigrant Asian American Women Residing in the San Francisco Bay Area

BACKGROUND

Breast cancer incidence rates in women of Asian descent have been increasing in the United States and Asia.

METHODS

In a case-control study of Asian American women from the San Francisco Bay Area, we assessed associations with birthplace and migration-related characteristics and compared risk factors between Asian American and non-Hispanic White women by birthplace and birth cohort.

RESULTS

Birthplace and migration-related characteristics were associated with breast cancer risk only among women in the younger birth cohort (1951-1984) that comprised 355 cases diagnosed at age ≤55 years and 276 sister and population controls. Breast cancer risk was marginally increased among foreign-born women [OR = 1.40; 95% confidence interval (CI), 0.97-2.03] and two-fold among foreign-born Chinese women (OR = 2.16; 95% CI, 1.21-3.88). Two-fold increased risks were associated with migration at age ≥40 years and longer U.S. residence (≥30 years or ≥75% of life). The education level was high among both cases and controls. Differences in the prevalence of risk factors by birthplace and birth cohort suggest temporal changes in reproductive and lifestyle-related factors. The prevalence in risk factors was similar between foreign-born and U.S.-born women in the younger birth cohort, and did not fully explain the observed associations with birthplace and other migration characteristics.

CONCLUSIONS

In contrast to studies from earlier decades, younger foreign-born Asian American women had a higher risk of breast cancer than U.S.-born Asian American women.

IMPACT

It is important and urgent to understand what factors drive the increasing burden of breast cancer in women of Asian descent and implement effective prevention programs.

The association between age at breast cancer diagnosis and prevalence of pathogenic variants

PURPOSE

Young age at breast cancer (BC) diagnosis and family history of BC are strongly associated with high prevalence of pathogenic variants (PVs) in BRCA1 and BRCA2 genes. There is limited evidence for such associations with moderate/high penetrance BC-risk genes such as ATM, CHEK2, and PALB2.

METHODS

We analyzed multi-gene panel testing results (09/2013-12/2019) for women unaffected by any cancer (N = 371,594) and those affected with BC (N = 130,151) ascertained for suspicion of hereditary breast and/or ovarian cancer. Multivariable logistic regression was used to test association between PV status and age at BC diagnosis (≤ 45 vs. > 45 years) or family history of BC after controlling for personal/family non-BC histories and self-reported ancestry.

RESULTS

An association between young age (≤ 45 years) at diagnosis and presence of PVs was strong for BRCA1 (OR 3.95, 95% CI 3.64-4.29) and moderate for BRCA2 (OR 1.98, 95% CI 1.84-2.14). Modest associations were observed between PVs and young age at diagnosis for ATM (OR 1.22, 95% CI 1.08-1.37) and CHEK2 (OR 1.34, 95% CI 1.21-1.47) genes, but not for PALB2 (OR 1.12, 95% CI 0.98-1.27). For women with BC, earliest age of familial BC diagnosis followed a similar pattern. For unaffected women, earliest age of family cancer diagnosis was significantly associated with PV status only for BRCA1 (OR 2.34, 95% CI 2.13-2.56) and BRCA2 (OR 1.25, 95% CI 1.16-1.35).

CONCLUSIONS

Young age at BC diagnosis is not a strong risk factor for carrying PVs in BC-associated genes ATM, CHEK2, or PALB2.

Emotion regulation and choice of bilateral mastectomy for the treatment of unilateral breast cancer

BACKGROUND

There has been steadily increasing use of bilateral mastectomy (BMX) in the treatment of primary breast cancer (BC). In this study, we utilized functional magnetic resonance imaging (fMRI) to examine the influence of emotion regulation on the decision of newly diagnosed BC patients to choose BMX rather than non-BMX treatments.

METHODS

We recruited 123 women with unilateral BC, 61 of whom received BMX and 62 of whom received non-BMX treatments, and 39 healthy controls. While participants were in the fMRI scanner, we showed them BC-related and non-BC-negative images. In one condition, they were instructed to watch the images naturally. In another, they were instructed to regulate their negative emotion. We compared the fMRI signal during these conditions throughout the brain.

RESULTS

With non-BC-negative images as the baseline, BC patients showed greater self-reported reactivity and neural reactivity to BC-related images in brain regions associated with self-reflection than did controls. Among the BC patients, the BMX group showed weaker activation in prefrontal emotion regulation brain regions during emotion regulation than did the non-BMX group.

CONCLUSIONS

BC patients are understandably emotionally hyper-reactive to BC-related stimuli and those who ultimately received BMX experience more difficulty in regulating BC-related negative emotion than non-BMX BC patients. These findings offer neuropsychological evidence that difficulty in managing anxiety related to the possibility of cancer recurrence is a factor in surgical treatment decision-making and may be an intervention target with the goal of strengthening the management of cancer-related anxiety by nonsurgical means.

TRIAL REGISTRATION

NCT03050463.

Antimicrobial exposure is associated with decreased survival in triple-negative breast cancer

Antimicrobial exposure during curative-intent treatment of triple-negative breast cancer (TNBC) may lead to gut microbiome dysbiosis, decreased circulating and tumor-infiltrating lymphocytes, and inferior outcomes. Here, we investigate the association of antimicrobial exposure and peripheral lymphocyte count during TNBC treatment with survival, using integrated electronic medical record and California Cancer Registry data in the Oncoshare database. Of 772 women with stage I-III TNBC treated with and without standard cytotoxic chemotherapy - prior to the immune checkpoint inhibitor era - most (654, 85%) used antimicrobials. Applying multivariate analyses, we show that each additional total or unique monthly antimicrobial prescription is associated with inferior overall and breast cancer-specific survival. This antimicrobial-mortality association is independent of changes in neutrophil count, is unrelated to disease severity, and is sustained through year three following diagnosis, suggesting antimicrobial exposure negatively impacts TNBC survival. These results may inform mechanistic studies and antimicrobial prescribing decisions in TNBC and other hormone receptor-independent cancers.

Breast Cancer Diagnosis, Treatment, and Outcomes of Patients From Sex and Gender Minority Groups

Importance

Sexual orientation and gender identity data are not collected by most hospitals or cancer registries; thus, little is known about the quality of breast cancer treatment for patients from sex and gender minority (SGM) groups.

Objective

To evaluate the quality of breast cancer treatment and recurrence outcomes for patients from SGM groups compared with cisgender heterosexual patients.

Design, Setting, and Participants

Exposure-matched retrospective case-control study of 92 patients from SGM groups treated at an academic medical center from January 1, 2008, to January 1, 2022, matched to cisgender heterosexual patients with breast cancer by year of diagnosis, age, tumor stage, estrogen receptor status, and ERBB2 (HER2) status.

Main Outcomes and Measures

Patient demographic and clinical characteristics, as well as treatment quality, as measured by missed guideline-based breast cancer screening, appropriate referral for genetic counseling and testing, mastectomy vs lumpectomy, receipt of chest reconstruction, adjuvant radiation therapy after lumpectomy, neoadjuvant chemotherapy for stage III disease, antiestrogen therapy for at least 5 years for estrogen receptor-positive disease, ERBB2-directed therapy for ERBB2-positive disease, patient refusal of an oncologist-recommended treatment, time from symptom onset to tissue diagnosis, time from diagnosis to first treatment, and time from breast cancer diagnosis to first recurrence. Results were adjusted for multiple hypothesis testing. Compared with cisgender heterosexual patients, those from SGM groups were hypothesized to have disparities in 1 or more of these quality metrics.

Results

Ninety-two patients from SGM groups were matched to 92 cisgender heterosexual patients (n = 184). The median age at diagnosis for all patients was 49 years (IQR, 43-56 years); 74 were lesbian (80%), 12 were bisexual (13%), and 6 were transgender (6%). Compared with cisgender heterosexual patients, those from SGM groups experienced a delay in time from symptom onset to diagnosis (median time to diagnosis, 34 vs 64 days; multivariable adjusted hazard ratio, 0.65; 95% CI, 0.42-0.99; P = .04), were more likely to decline an oncologist-recommended treatment modality (35 [38%] vs 18 [20%]; multivariable adjusted odds ratio, 2.27; 95% CI, 1.09-4.74; P = .03), and were more likely to experience a breast cancer recurrence (multivariable adjusted hazard ratio, 3.07; 95% CI, 1.56-6.03; P = .001).

Conclusions and Relevance

This study found that among patients with breast cancer, those from SGM groups experienced delayed diagnosis, with faster recurrence at a 3-fold higher rate compared with cisgender heterosexual patients. These results suggest disparities in the care of patients from SGM groups and warrant further study to inform interventions.

Contralateral Breast Cancer Risk Among Carriers of Germline Pathogenic Variants in ATM, BRCA1, BRCA2, CHEK2, and PALB2

PURPOSE

To estimate the risk of contralateral breast cancer (CBC) among women with germline pathogenic variants (PVs) in ATM, BRCA1, BRCA2, CHEK2, and PALB2.

METHODS

The study population included 15,104 prospectively followed women within the CARRIERS study treated with ipsilateral surgery for invasive breast cancer. The risk of CBC was estimated for PV carriers in each gene compared with women without PVs in a multivariate proportional hazard regression analysis accounting for the competing risk of death and adjusting for patient and tumor characteristics. The primary analyses focused on the overall cohort and on women from the general population. Secondary analyses examined associations by race/ethnicity, age at primary breast cancer diagnosis, menopausal status, and tumor estrogen receptor (ER) status.

RESULTS

Germline BRCA1, BRCA2, and CHEK2 PV carriers with breast cancer were at significantly elevated risk (hazard ratio > 1.9) of CBC, whereas only the PALB2 PV carriers with ER-negative breast cancer had elevated risks (hazard ratio, 2.9). By contrast, ATM PV carriers did not have significantly increased CBC risks. African American PV carriers had similarly elevated risks of CBC as non-Hispanic White PV carriers. Among premenopausal women, the 10-year cumulative incidence of CBC was estimated to be 33% for BRCA1, 27% for BRCA2, and 13% for CHEK2 PV carriers with breast cancer and 35% for PALB2 PV carriers with ER-negative breast cancer. The 10-year cumulative incidence of CBC among postmenopausal PV carriers was 12% for BRCA1, 9% for BRCA2, and 4% for CHEK2.

CONCLUSION

Women diagnosed with breast cancer and known to carry germline PVs in BRCA1, BRCA2, CHEK2, or PALB2 are at substantially increased risk of CBC and may benefit from enhanced surveillance and risk reduction strategies.

Abstract P6-02-07: Uptake of Breast Cancer MRI Screening in Patients After Multiplex Gene Panel Testing

Purpose: Multiplex gene panel testing (MGPT) is used to identify individuals with an inherited susceptibility to cancer. However, little is known about the uptake of screening and surveillance among patients after MGPT and genetic counseling. The purpose of this study was to measure the uptake of guideline-concordant breast cancer screening after genetic testing and counseling.

Patients and Methods: 2,000 patients who met NCCN testing guidelines or had ≥2.5% probability of a pathogenic/likely pathogenic variant (PV) were recruited at three cancer genetics clinics (University of Southern California (USC) Norris Comprehensive Cancer Center, Los Angeles County + USC Medical Center, Stanford Cancer Institute) from July 2014 through November 2016. All patients had 25- or 28-gene MGPT and results were disclosed by a genetic counselor, who provided screening recommendations to patients based on their risk. Post-test surveys were administered at three months, six months, one year, two years, and three years.

Results: 1,614/2,000 (80.7%) patients were female and 1,147/1,614 (71.7%) completed at least one survey regarding MRI screening for breast cancer over the three years of longitudinal follow-up. Of these, 94/1,147 (8.2%) patients tested positive for at least one PV in a breast cancer risk gene; 58/94 (61.7%) tested positive for PVs in a high-risk breast cancer gene (BRCA1/2 (n=53), CDH1, PALB2, TP53 (n=5)), and 34/94 (36.2%) of patients tested positive for a PV in a gene characterized as moderate-risk at the time of disclosure (CHEK2, ATM, NBN). MRIs were recommended to 43/58 (74.1%) patients with a high-risk breast cancer gene PV, 20/34 (58.8%) patients with a moderate-risk gene PV, and 171/1,053 (16.2%) patients without a breast cancer risk gene PV. Multivariate logistic regression models revealed that patients with a high-risk gene PV were more likely to undergo MRI screening within 3 months of receiving genetic test results (OR=6.54 95% CI [3.09 - 14.43], p&lt; 0.001), within one year (OR=1.34 95% CI [1.18 - 1.52], p&lt; 0.001), two years (OR=1.43 95% CI [1.24 – 1.65], p&lt; 0.001), and three years (OR=1.44 95% CI [1.25 – 1.66], p&lt; 0.001) when compared to patients without a PV. Patients with a moderate-risk PV were also more likely to have undergone MRI within 3 months of receiving genetic test results (OR=2.89 95% CI [1.05 - 7.81], p=0.036), within one year (OR=1.33 95% CI [1.10 - 1.62], p=0.004), two years (OR=1.31 95% CI [1.09 - 1.59], p=0.004), and three years (OR=1.44 95% CI [1.18 - 1.76], p&lt; 0.001), compared to those without a PV (Table 1).

Conclusions: After three years of longitudinal follow up of 2000 patients in this multicenter prospective cohort study, patients with a PV in a breast cancer susceptibility gene were more likely to undergo guideline concordant breast MRI compared to patients without a PV. Carriers of high-risk breast cancer gene PVs were over six times as likely to have undergone MRI compared to patients without PVs within the first three months after genetic results disclosure and counseling. These results demonstrate the effectiveness of MGPT and genetic counseling in guiding patients with PVs in breast cancer susceptibility genes to the appropriate adoption of guideline-concordant screening.

Odds ratios of MRI screening in patients carrying PV in breast cancer risk genes. Odds in relation to patients who do not carry a PV High risk gene PV: BRCA1/2, CDH1, PALB2, TP53; Moderate Risk PV: CHEK2, ATM, NBN.

Percent of patients having undergone an MRI at the specified time points High risk gene PV: BRCA1/2, CDH1, PALB2, TP53; Moderate Risk PV: CHEK2, ATM, NBN.

Citation Format: Leah A. Naghi, Charite N. Ricker, Duveen Sturgeon, Julie Culver, Kerry Kingham, Rachel Hodan, Nicolette M. Chun, John Kidd, Joseph Bonner, Christine Hong, Meredith Mills, Sidney S. Lindsey, Kevin McDonnell, Uri Ladabaum, James M. Ford, Stephen Grube, Allison W. Kurian, Gregory E. Idos. Uptake of Breast Cancer MRI Screening in Patients After Multiplex Gene Panel Testing [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 P6-02-07.

Association of the CHEK2 c.1100delC variant, radiotherapy, and systemic treatment with contralateral breast cancer risk and breast cancer-specific survival

Breast cancer (BC) patients with a germline CHEK2 c.1100delC variant have an increased risk of contralateral BC (CBC) and worse BC-specific survival (BCSS) compared to non-carriers. We aimed to assess the associations of CHEK2 c.1100delC, radiotherapy, and systemic treatment with CBC risk and BCSS. Analyses were based on 82,701 women diagnosed with invasive BC including 963 CHEK2 c.1100delC carriers; median follow-up was 9.1 years. Differential associations of treatment by CHEK2 c.1100delC status were tested by including interaction terms in a multivariable Cox regression model. A multi-state model was used for further insight into the relation between CHEK2 c.1100delC status, treatment, CBC risk and death. There was no evidence for differential associations of therapy with CBC risk by CHEK2 c.1100delC status The strongest association with reduced CBC risk was observed for the combination of chemotherapy and endocrine therapy [HR(95%CI): 0.66 (0.55-0.78)]. No association was observed with radiotherapy. Results from the multi-state model showed shorter BCSS for CHEK2 c.1100delC carriers versus non-carriers also after accounting for CBC occurrence [HR(95%CI) :1.30 (1.09-1.56)]. In conclusion, systemic therapy was associated with reduced CBC risk irrespective of CHEK2 c.1100delC status. Moreover, CHEK2 c.1100delC carriers had shorter BCSS, which appears not to be fully explained by their CBC risk. (Main MS: 3201 words).

Reassessing the Benefits and Harms of Risk-Reducing Medication Considering the Persistent Risk of Breast Cancer Mortality in Estrogen Receptor-Positive Breast Cancer

PURPOSE

Recent studies, including a meta-analysis of 88 trials, have shown higher than expected rates of recurrence and death in hormone receptor-positive breast cancer. These new findings suggest a need to re-evaluate the use of risk-reducing medication to avoid invasive breast cancer and breast cancer death in high-risk women.

METHODS

We adapted an established Cancer Intervention and Surveillance Modeling Network model to evaluate the lifetime benefits and harms of risk-reducing medication in women with a ≥ 3% 5-year risk of developing breast cancer according to the Breast Cancer Surveillance Consortium risk calculator. Model input parameters were derived from meta-analyses, clinical trials, and large observational data. We evaluated the effects of 5 years of risk-reducing medication (tamoxifen/aromatase inhibitors) with annual screening mammography ± magnetic resonance imaging (MRI) compared with no screening, MRI, or risk-reducing medication. The modeled outcomes included invasive breast cancer, breast cancer death, side effects, false positives, and overdiagnosis. We conducted subgroup analyses for individual risk factors such as age, family history, and prior biopsy.

RESULTS

Risk-reducing tamoxifen with annual screening (± MRI) decreased the risk of invasive breast cancer by 40% and breast cancer death by 57%, compared with no tamoxifen or screening. This is equivalent to an absolute reduction of 95 invasive breast cancers, and 42 breast cancer deaths per 1,000 high-risk women. However, these drugs are associated with side effects. For example, tamoxifen could increase the number of endometrial cancers up to 11 per 1,000 high-risk women. Benefits and harms varied by individual characteristics.

CONCLUSION

The addition of risk-reducing medication to screening could further decrease the risk of breast cancer death. Clinical guidelines for high-risk women should consider integrating shared decision making for risk-reducing medication and screening on the basis of individual risk factors.

Aggregation tests identify new gene associations with breast cancer in populations with diverse ancestry

BACKGROUND

Low-frequency variants play an important role in breast cancer (BC) susceptibility. Gene-based methods can increase power by combining multiple variants in the same gene and help identify target genes.

METHODS

We evaluated the potential of gene-based aggregation in the Breast Cancer Association Consortium cohorts including 83,471 cases and 59,199 controls. Low-frequency variants were aggregated for individual genes' coding and regulatory regions. Association results in European ancestry samples were compared to single-marker association results in the same cohort. Gene-based associations were also combined in meta-analysis across individuals with European, Asian, African, and Latin American and Hispanic ancestry.

RESULTS

In European ancestry samples, 14 genes were significantly associated (q < 0.05) with BC. Of those, two genes, FMNL3 (P = 6.11 × 10-6) and AC058822.1 (P = 1.47 × 10-4), represent new associations. High FMNL3 expression has previously been linked to poor prognosis in several other cancers. Meta-analysis of samples with diverse ancestry discovered further associations including established candidate genes ESR1 and CBLB. Furthermore, literature review and database query found further support for a biologically plausible link with cancer for genes CBLB, FMNL3, FGFR2, LSP1, MAP3K1, and SRGAP2C.

CONCLUSIONS

Using extended gene-based aggregation tests including coding and regulatory variation, we report identification of plausible target genes for previously identified single-marker associations with BC as well as the discovery of novel genes implicated in BC development. Including multi ancestral cohorts in this study enabled the identification of otherwise missed disease associations as ESR1 (P = 1.31 × 10-5), demonstrating the importance of diversifying study cohorts.

Abstract P055: Risk factors for second primary lung cancer among breast cancer survivors

Introduction: Breast cancer is the most common cancer in women in the U.S. As survival in breast cancer has improved, one of the key clinical problems in breast cancer survivors is the increased risk of second cancers. Over half (55%) of breast cancer survivors die from second cancers, of which lung cancer (i.e., second primary lung cancer [SPLC]) is the most frequent type. While smoking and radiotherapy have been identified as the risk factors for SPLC among breast cancer survivors, other potential factors (e.g., comorbidity, and medication) have been underexamined. In addition, women in general have shown higher susceptibility to smoking-induced lung cancer than men, suggesting the potential involvement of hormonal factors; however, the effect of hormone replacement therapy (HRT) on lung cancer risk has been controversial and has never been examined among breast cancer survivors. We aimed to examine the factors associated with SPLC risk among breast cancer survivors, focusing on the effect of HRT and its interaction with smoking. We also explored the potential of tailored risk-based management of SPLC for breast cancer survivors. Methods: We identified 5,552 patients diagnosed with breast cancer in 1993-2014 from the Prostate, Lung, Colorectal, and Ovarian Cancer (PLCO) Screening Trial. SPLC was defined as a newly diagnosed lung cancer after 6 months from the time of breast cancer diagnosis. We applied multivariable cause-specific Cox regression to identify new factors associated with SPLC risk, adjusting for multiple testing using the Bonferroni method (P&lt;0.01). We developed a prediction model to predict a 5-year risk of SPLC among breast cancer survivors that included both ever- and never-smokers and evaluated the predictive accuracy vs. a well-established lung cancer risk model, PLCOm2012, that was developed for a cancer-free population who ever smoked. Results: Of 5,552 patients, 89 (1.6%) developed SPLC over 102,545 person-years. Several factors measured at baseline in PLCO were significantly associated with SPLC risk among breast cancer survivors, including liver comorbidity (Hazard Ratio [HR] 3.28; P&lt;.001), prior history of other cancer (HR 2.02; P=0.01), and regular use of ibuprofen (HR 0.52; P=0.01). In addition, ever-use of HRT was associated with a 51% reduction in SPLC risk (HR 0.49; P=0.001). The effect of active smoking on SPLC risk vs non-active smoking (HR 7.09; P&lt;.001) was validated in PLCO. Notably, the effect of active smoking was intensified among ever-HRT users (HR=10.5; P&lt;.001) vs. never-HRT users (HR 4.1; P&lt;.001), thus showing a significant interaction (Pinteraction=0.003). The prediction model for SPLC risk was validated through bootstrap and demonstrated higher discrimination (AUC 0.83) vs. the PLCOm2012 model (AUC 0.79). Conclusions: In a large prospective cohort of breast cancer survivors, smoking and HRT use showed a significant interaction on SPLC risk. The prediction model for SPLC could identify high-risk survivors for SPLC for tailored surveillance to improve the management of breast cancer survivors.

Citation Format: Eunji Choi, Justin Lee, Julie T. Wu, Heather A. Wakelee, Lidia Schapira, Allison W. Kurian, Summer S. Han. Risk factors for second primary lung cancer among breast cancer survivors. [abstract]. In: Proceedings of the AACR Special Conference: Precision Prevention, Early Detection, and Interception of Cancer; 2022 Nov 17-19; Austin, TX. Philadelphia (PA): AACR; Can Prev Res 2023;16(1 Suppl): Abstract nr P055.

Abstract P068: A hybrid modelling approach for abstracting CT imaging indications by integrating natural language processing from radiology reports with structured data from electronic health records

Background: Real-world evidence (RWE) studies for surveillance patterns following lung cancer (LC) diagnosis can inform optimizing recommendations on surveillance and practice. One major obstacle in RWE studies for LC surveillance is the lack of radiologic imaging indication for surveillance vs. other reasons (e.g., symptoms). To enable RWE studies for surveillance to detect second primary lung cancer among LC survivors, we developed a hybrid modelling approach that integrates structured data from electronic health records (EHRs) with natural language processing (NLP) from radiology reports for abstracting computed tomography (CT) imaging indications in LC survivors. Methods: We manually reviewed and abstracted CT imaging indications, i.e., surveillance vs. others (e.g., symptoms and metastatic disease follow-up) to create a gold standard from 200 randomly selected radiology reports among 1,952 LC patients (i) who were diagnosed in 2000-2017 at Stanford Health Care (SHC) and (ii) survived ≧5 years after the diagnosis. We abstracted medically relevant key-phrases using the part-of-speech grammar and PageRank algorithms. Hierarchical clustering identified context-specific key-phrase clusters as follows: “surveillance”, “stable”, “nodule”, “symptom”, and “metastasis”. The text-based radiology reports were vectorized to generate NLP features using phrase occurrence frequencies. The structured variables from EHRs included: (i) diagnosis of lung diseases or chest symptoms in previous 6 months, (ii) ordering provider-type (oncology vs. others [e.g. emergency and internal medicine]), and (iii) time from previous CT (≧6 months). A hybrid model was then fitted using logistic regression including both structured and NLP features and validated using a 10-fold cross-validation. The model’s performance was compared to those solely based on NLP or structured data. Results: The dataset of 200 radiology reports included 141 LC survivors (49% White, 72% adenocarcinoma). The proposed hybrid model showed high discrimination (AUC: 0.92), outperforming those based solely on NLP (AUC: 0.88) or structured data (AUC: 0.87). The proposed model demonstrated higher sensitivity (SN: 0.73) and specificity (SP: 0.96) versus those solely based on NLP (SN: 0.53; SP: 0.96) or structured data (SN: 0.53; SP: 0.90). The hybrid model showed that the following variables were positively associated with a higher likelihood that the given CT imaging indication is “surveillance”: (i) a longer time interval (≧6 months) from the previous CT (odds ratio [OR]: 4.63; p=0.01) and key-phrases of (ii) “nodule” (OR: 1.55; p=0.004) and (iii) “stable” (OR: 1.37; p=0.03). On the other hand, the following were negatively associated with the likelihood of surveillance: the key-phrases of “symptom” (OR: 0.17; p=0.02) and “metastasis” (OR: 0.26; p=0.02). Conclusion: A hybrid modeling approach combining text-based NLP and structured EHRs has the potential for abstracting CT imaging indications for LC surveillance. Future directions include validation using other EHR systems and extension using larger data.

Citation Format: Aparajita Khan, Julie Wu, Eunji Choi, Anna Graber-Naidich, Solomon Henry, Heather A. Wakelee, Allison W. Kurian, Su-Ying Liang, Ann Leung, Curtis Langlotz, Leah M. Backhus, Summer S. Han. A hybrid modelling approach for abstracting CT imaging indications by integrating natural language processing from radiology reports with structured data from electronic health records. [abstract]. In: Proceedings of the AACR Special Conference: Precision Prevention, Early Detection, and Interception of Cancer; 2022 Nov 17-19; Austin, TX. Philadelphia (PA): AACR; Can Prev Res 2023;16(1 Suppl): Abstract nr P068.

Cascade Testing for Hereditary Cancer Syndromes: Should We Move Toward Direct Relative Contact? A Systematic Review and Meta-Analysis

PURPOSE

Evidence-based guidelines recommend cascade genetic counseling and testing for hereditary cancer syndromes, providing relatives the opportunity for early detection and prevention of cancer. The current standard is for patients to contact and encourage relatives (patient-mediated contact) to undergo counseling and testing. Direct relative contact by the medical team or testing laboratory has shown promise but is complicated by privacy laws and lack of infrastructure. We sought to compare outcomes associated with patient-mediated and direct relative contact for hereditary cancer cascade genetic counseling and testing in the first meta-analysis on this topic.

MATERIALS AND METHODS

We conducted a systematic review and meta-analysis in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PROSPERO No.: CRD42020134276). We searched key electronic databases to identify studies evaluating hereditary cancer cascade testing. Eligible trials were subjected to meta-analysis.

RESULTS

Eighty-seven studies met inclusion criteria. Among relatives included in the meta-analysis, 48% (95% CI, 38 to 58) underwent cascade genetic counseling and 41% (95% CI, 34 to 48) cascade genetic testing. Compared with the patient-mediated approach, direct relative contact resulted in significantly higher uptake of genetic counseling for all relatives (63% [95% CI, 49 to 75] v 35% [95% CI, 24 to 48]) and genetic testing for first-degree relatives (62% [95% CI, 49 to 73] v 40% [95% CI, 32 to 48]). Methods of direct contact included telephone calls, letters, and e-mails; respective rates of genetic testing completion were 61% (95% CI, 51 to 70), 48% (95% CI, 37 to 59), and 48% (95% CI, 45 to 50).

CONCLUSION

Most relatives at risk for hereditary cancer do not undergo cascade genetic counseling and testing, forgoing potentially life-saving medical interventions. Compared with patient-mediated contact, direct relative contact increased rates of cascade genetic counseling and testing, arguing for a shift in the care delivery paradigm, to be confirmed by randomized controlled trials.

Genome- and transcriptome-wide association studies of 386,000 Asian and European-ancestry women provide new insights into breast cancer genetics

By combining data from 160,500 individuals with breast cancer and 226,196 controls of Asian and European ancestry, we conducted genome- and transcriptome-wide association studies of breast cancer. We identified 222 genetic risk loci and 137 genes that were associated with breast cancer risk at a p < 5.0 × 10^-8 and a Bonferroni-corrected p < 4.6 × 10^-6, respectively. Of them, 32 loci and 15 genes showed a significantly different association between ER-positive and ER-negative breast cancer after Bonferroni correction. Significant ancestral differences in risk variant allele frequencies and their association strengths with breast cancer risk were identified. Of the significant associations identified in this study, 17 loci and 14 genes are located 1Mb away from any of the previously reported breast cancer risk variants. Pathways analyses including 221 putative risk genes identified multiple signaling pathways that may play a significant role in the development of breast cancer. Our study provides a comprehensive understanding of and new biological insights into the genetics of this common malignancy.

Examining Associations Among Sexual Health, Unmet Care Needs, and Distress in Breast and Gynecologic Cancer Survivors

OBJECTIVES

This study evaluated breast and gynecologic cancer patients' sexual function, unmet needs related to sexuality, and distress.

DATA SOURCES

Secondary analyses of a cross-sectional survey study evaluated measures of sexual function (Female Sexual Function Index [FSFI]), unmet needs (Supportive Care Needs Scale), and distress (Patient Health Questionnaire). χ² test, t tests, and analysis of variances (ANOVAs) tested bivariate relationships. Subgroup comparisons were made based on the Female Sexual Function Index sexual dysfunction diagnostic cut-off score (<26.55; lower scores indicate greater dysfunction). A regression model tested associations between sexual function and unmet needs with distress as the outcome variable.

CONCLUSION

Clinically significant sexual dysfunction was common in this cohort of women. In multivariate modeling, worse sexual function and greater unmet sexuality needs related to greater distress. Future work should explore reasons behind the high levels of sexual dysfunction and unmet needs in female survivors.

IMPLICATIONS FOR NURSING PRACTICE

It is important to routinely screen for sexual health concerns among female cancer survivors at all phases of the cancer trajectory including years posttreatment.

Symptoms and survivorship needs differences between "good sleepers" and "bad sleepers" in survivors of breast and gynecologic cancers

INTRODUCTION

Although 80% of cancer survivors report symptoms of insomnia, only 28-43% meet DSM-5 criteria for this diagnosis. We sought to characterize the association between patient-reported insomnia symptoms, patient outcomes, and supportive care variables, as well as explore clinically meaningful insomnia thresholds in a sample of women diagnosed with breast and gynecologic cancers.

METHODS

From July 2018-March 2019, all breast and gynecologic cancer survivors seen at the Stanford Women's Cancer Center were approached and invited to participate in the study (15% declined). Of those who consented, 273 survivors completed an online survey related to their sleep (ISI), quality of life (FACT-G), distress (PHQ-4), supportive care needs (SCNS-SF34), and symptom severity (MDASI). Survivors who scored <8 on ISI were categorized as "good sleepers," survivors with ISI ≥8 were categorized as "bad sleepers."

RESULTS

126 (46.2%) of survivors were "good sleepers," 147 (53.8%) were "bad sleepers." Good sleepers were older than bad sleepers (p < .05) but did not differ in any other demographic or any medical variables. Using hierarchical linear regression models, we found that good sleep (ISI <8) was associated with higher quality of life, lower psychological distress, increased social support, lower symptom severity, and lower supportive care needs, after accounting for demographic, medical, and treatment variables. The findings were largely replicated with an ISI cut off of 15.

CONCLUSIONS

Among women treated for breast and gynecologic cancers, survivors who were good sleepers had better psychosocial outcomes, fewer supportive care needs, and lower symptom severity compared to those who reported insomnia symptoms. Results also indicate that degree of sleep impairment, whether mild or severe, has similarly poor associations with most aspects of patient functioning and symptomatic burden. Further research is needed to determine causality of these findings.

Constitutional BRCA1 Methylation and Risk of Incident Triple-Negative Breast Cancer and High-grade Serous Ovarian Cancer

Importance

About 25% of all triple-negative breast cancers (TNBCs) and 10% to 20% of high-grade serous ovarian cancers (HGSOCs) harbor BRCA1 promoter methylation. While constitutional BRCA1 promoter methylation has been observed in normal tissues of some individuals, the potential role of normal tissue methylation as a risk factor for incident TNBC or HGSOC is unknown.

Objective

To assess the potential association between white blood cell BRCA1 promoter methylation and subsequent risk of incident TNBC and HGSOC.

Design, Setting, and Participants

This case-control study included women who were participating in the Women's Health Initiative study who had not received a diagnosis of either breast or ovarian cancer before study entrance. A total of 637 women developing incident TNBC and 511 women developing incident HGSOC were matched with cancer-free controls (1841 and 2982, respectively) in a nested case-control design. Cancers were confirmed after central medical record review. Blood samples, which were collected at entry, were analyzed for BRCA1 promoter methylation by massive parallel sequencing. The study was performed in the Mohn Cancer Research Laboratory (Bergen, Norway) between 2019 and 2022.

Main Outcomes and Measures

Associations between BRCA1 methylation and incident TNBC and incident HGSOC were analyzed by Cox proportional hazards regression.

Results

Of 2478 cases and controls in the TNBC group and 3493 cases and controls in the HGSOC group, respectively, 7 (0.3%) and 3 (0.1%) were American Indian or Alaska Native, 46 (1.9%) and 30 (0.9%) were Asian, 1 (0.04%) and 1 (0.03%) was Native Hawaiian or Pacific Islander, 326 (13.2%) and 125 (3.6%) were Black or African, 56 (2.3%) and 116 (3.3%) were Hispanic, 2046 (82.6%) and 3257 (93.2%) were White, and 35 (1.4%) and 35 (1.0%) were multiracial. Median (range) age at entry was 62 (50-79) years, with a median interval to diagnosis of 9 (TNBC) and 10 (HGSOC) years. Methylated BRCA1 alleles were present in 194 controls (5.5%). Methylation was associated with risk of incident TNBC (12.4% methylated; HR, 2.35; 95% CI, 1.70-3.23; P < .001) and incident HGSOC (9.4% methylated; HR, 1.93; 95% CI, 1.36-2.73; P < .001). Restricting analyses to individuals with more than 5 years between sampling and cancer diagnosis yielded similar results (TNBC: HR, 2.52; 95% CI, 1.75-3.63; P < .001; HGSOC: HR, 1.82; 95% CI, 1.22-2.72; P = .003). Across individuals, methylation was not haplotype-specific, arguing against an underlying cis-acting factor. Within individuals, BRCA1 methylation was observed on the same allele, indicating clonal expansion from a single methylation event. There was no association found between BRCA1 methylation and germline pathogenic variant status.

Conclusions and Relevance

The results of this case-control suggest that constitutional normal tissue BRCA1 promoter methylation is significantly associated with risk of incident TNBC and HGSOC, with potential implications for prediction of these cancers. These findings warrant further research to determine if constitutional methylation of tumor suppressor genes are pancancer risk factors.

Reducing the risk of breast cancer

Breast cancer remains the most common female malignancy in the United States. Reducing this cancer burden involves identification of high-risk individuals and personalized risk management. Because coronary artery disease remains the primary cause of death for women, any intervention to reduce breast cancer risk must be weighed against comorbidities and interventions affecting cardiovascular risk reduction. For select women at increased risk for breast cancer, preventive medication can greatly decrease risk and is vastly underutilized. Women's health clinicians are poised to evaluate risk, promote breast cancer risk reduction, and manage overall health.

A pilot study to increase cascade genetic risk education and testing in families with hereditary cancer syndromes

378

Background: There is great need to build and evaluate tools and strategies to improve cascade genetic risk evaluation in families at high risk for hereditary cancer. The Genetic Information and Family Testing (GIFT) Trial is a population-based intervention that will examine features of a virtual platform that provides genetic risk education (GRE) and low-cost genetic testing (GT) to relatives of 5000 adult patients diagnosed with cancer in 2018-19 in Georgia and California and who tested positive for a clinically actionable germline pathogenic variant (PV). We present findings of a pilot study that informed the GIFT Trial protocol and platform features. Methods: We surveyed 277 women diagnosed with breast cancer in 2017, reported to the Georgia SEER registry, and who tested positive for a clinically actionable PV in a cancer-associated gene. We then invited respondent patients to enroll in the intervention phase which provided online GRE, human pretest genetic navigator support, and an offer of low-cost GT through Color Health, Inc. to all untested 1st or 2nd degree relatives. Respondent patients were eligible for the intervention if they reported a PV on genetic testing and had at least one relative who had not received GT. Enrolled patients invited relatives through the platform by providing email addresses. Family clusters were block randomized to free vs $50 test costs at the time of the initial patient invitation. Results: 125 of 277 patients (45.2%) returned surveys: median age was 51 and 22% were African American. The most common PV reported by patients were BRCA2 (25.7%), BRCA1 (19.5%), CHEK2 (20.4%), ATM (8.8%) and PALB2 (7.1%). Disclosure of genetic test results to relatives was quite high: 83.6% of patients reported that they discussed results with all their daughters vs 69.4% with sons; 78.1% discussed their results with all sisters vs 61.8% with all brothers. The median number of patient-reported untested relatives in a family was 9 (25th-75th percentile: 4-14). Most respondents were eligible for the trial offer (113 of 125, 90.4%). Overall, results were similar between the free test arm and $50 test arm: In the free testing arm, 20 patient participants invited 28 relatives; 12 relatives enrolled, and all 12 relatives ordered testing. In the $50 arm, 16 patient participants invited 38 relatives of whom 18 enrolled and all 18 ordered testing. For the 66 relatives invited by the patient participants: 47 (71.2%) were first degree (8 parents, 22 siblings, and 17 children) and about half of the relatives were men (47.0%). Conclusions: Breast cancer patients with PVs make substantial efforts to communicate with family members about genetic risk but most relatives do not receive GT. Our study findings suggest that a low-cost online navigator-supported intervention can directly engage relatives to increase cascade genetic risk education and testing with little difference in uptake by test cost arms.

Physical activity, sedentary time and breast cancer risk: a Mendelian randomisation study

OBJECTIVES

Physical inactivity and sedentary behaviour are associated with higher breast cancer risk in observational studies, but ascribing causality is difficult. Mendelian randomisation (MR) assesses causality by simulating randomised trial groups using genotype. We assessed whether lifelong physical activity or sedentary time, assessed using genotype, may be causally associated with breast cancer risk overall, pre/post-menopause, and by case-groups defined by tumour characteristics.

METHODS

We performed two-sample inverse-variance-weighted MR using individual-level Breast Cancer Association Consortium case-control data from 130 957 European-ancestry women (69 838 invasive cases), and published UK Biobank data (n=91 105-377 234). Genetic instruments were single nucleotide polymorphisms (SNPs) associated in UK Biobank with wrist-worn accelerometer-measured overall physical activity (nsnps=5) or sedentary time (nsnps=6), or accelerometer-measured (nsnps=1) or self-reported (nsnps=5) vigorous physical activity.

RESULTS

Greater genetically-predicted overall activity was associated with lower breast cancer overall risk (OR=0.59; 95% confidence interval (CI) 0.42 to 0.83 per-standard deviation (SD;~8 milligravities acceleration)) and for most case-groups. Genetically-predicted vigorous activity was associated with lower risk of pre/perimenopausal breast cancer (OR=0.62; 95% CI 0.45 to 0.87,≥3 vs. 0 self-reported days/week), with consistent estimates for most case-groups. Greater genetically-predicted sedentary time was associated with higher hormone-receptor-negative tumour risk (OR=1.77; 95% CI 1.07 to 2.92 per-SD (~7% time spent sedentary)), with elevated estimates for most case-groups. Results were robust to sensitivity analyses examining pleiotropy (including weighted-median-MR, MR-Egger).

CONCLUSION

Our study provides strong evidence that greater overall physical activity, greater vigorous activity, and lower sedentary time are likely to reduce breast cancer risk. More widespread adoption of active lifestyles may reduce the burden from the most common cancer in women.

Chemotherapy Regimens Received by Women With BRCA1/2 Pathogenic Variants for Early Stage Breast Cancer Treatment

BACKGROUND

Genetic testing is widespread among breast cancer patients; however, no guideline recommends using germline genetic testing results to select a chemotherapy regimen. It is unknown whether breast cancer patients who carry pathogenic variants (PVs) in BRCA1 and/or 2 (BRCA1/2) or other cancer-associated genes receive different chemotherapy regimens than noncarriers.

METHODS

We linked Surveillance, Epidemiology, and End Results registry records from Georgia and California to germline genetic testing results from 4 clinical laboratories. Patients who 1) had stages I-III breast cancer, either hormone receptor (HR) positive and HER2 negative or triple negative (TNBC), diagnosed in 2013-2017; 2) received chemotherapy; and 3) were linked to genetic results were included. Chemotherapy details were extracted from Surveillance, Epidemiology, and End Results text fields completed by registrars. We examined whether PV carriers received more intensive regimens (HR-positive,HER2-negative: ≥3 drugs including an anthracycline; TNBC: ≥4 drugs including an anthracycline and platinum) and/or less standard breast cancer agents (a platinum). All statistical tests were 2-sided.

RESULTS

Among 2293 patients, 1451 had HR-positive, HER2-negative disease, and 842 had TNBC. On multivariable analysis of women with HR-positive, HER2-negative disease, receipt of a more intensive chemotherapy regimen varied statistically significantly by genetic results (P = .02), with platinum receipt more common among BRCA1/2 PV carriers (odds ratio = 2.44, 95% confidence interval = 1.36 to 4.38; P < .001). Among women with TNBC, chemotherapy agents did not vary significantly by genetic results.

CONCLUSION

BRCA1/2 PV carriers with HR-positive, HER2-negative breast cancer had twofold higher odds than noncarriers of receiving a platinum, as part of a more intensive chemotherapy regimen. This likely represents overtreatment and emphasizes the need to monitor how genetic testing results are managed in oncology practice.

A pilot study to increase cascade genetic testing in families with hereditary cancer syndromes

10602

Background: There is great need to build and evaluate tools and strategies to improve cascade genetic risk evaluation in families at high risk for hereditary cancer. The Genetic Information and Family Testing (GIFT) Trial (CA254822) is a population-based intervention that examines features of a virtual platform that provides genetic risk education (GRE) and low-cost genetic testing (GT) to relatives of adult patients diagnosed with cancer in 2018-19 in Georgia and California and tested positive for a clinically relevant germline pathogenic variant (PV). We present findings of a pilot study intended to inform the GIFT Trial protocol and platform features. Methods: We surveyed 277 women diagnosed with breast cancer in 2017, reported to the Georgia SEER registry, and received genetic testing (95% of whom had a clinically relevant PV). We then invited respondent patients to enroll in the intervention phase which provided online GRE, human pretest genetic navigator support, and an offer of low-cost GT through Color Health, Inc. to all untested 1st or 2nd degree relatives. Respondent patients were eligible for the intervention if they reported a PV on genetic testing and had at least one relative who had not received GT. Enrolled patients invited relatives through the platform by providing email addresses. Family clusters were block randomized to free vs $50 test costs at the time of the initial patient invitation. Results: At study midpoint, 117 of 277 patients (42%) had returned surveys: median age was 51 and 22% were African American. The most frequent PVs reported by the patients were BRCA1/2 (41%), CHEK2 (21%), and PALB2 (8%). Half (54%) had previously encouraged all of their brothers to get GT and 71% had encouraged all of their sisters to get GT. Three-quarters (78%) strongly agreed it was important for relatives to understand their genetic risk for cancer, and half (54%) strongly agreed they would like to make it easier for relatives to get genetic testing. The median number of patient-reported untested relatives in a family was 8.5 (25th-75th percentile: 4-14). Most respondent patients were eligible for the intervention phase (N = 108, 93%). About one-quarter had enrolled in the intervention at midpoint (16 of 53 in no-cost arm vs 16 of 55 in $50 arm). Patients in the no-cost arm invited 21 relatives, 10 of whom had enrolled with 8 ordering GT (38% of invited relatives). Patients in the $50 arm invited 38 relatives, 18 of whom had enrolled with 17 ordering GT (45% of invited relatives). Overall, about half of enrolled relatives (46%) were men. Conclusions: Breast cancer patients with PVs make substantial efforts to communicate with family members about genetic risk; but they strongly endorse the need for additional support to facilitate this complex communication. Interim pilot findings suggest that a low-cost online navigator-supported intervention can directly engage relatives with little difference in GT uptake by test cost arms.

Ancestry-specific risk of triple-negative breast cancer (TNBC) associated with germline pathogenic variants (PV) in hereditary cancer (CA) predisposition genes

10517

Background: TNBC represents ̃15% of invasive BC. Ancestry-specific variabilities in TNBC risk are well-described, with African American (AA) women experiencing higher incidence and mortality from TNBC than women of other races/ethnicities. Increased risk of TNBC has been associated with both rarer (e.g. RAD51C/D, BARD1) and more commonly detected (e.g. BRCA1/2, PALB2) germline PV in hereditary CA predisposition genes, but less is known about ancestry-specific TNBC risks for PV carriers. Methods: We examined clinical and genetic records from women referred for multigene CA panel testing (9/2013-5/2020). Multivariable logistic regression was used to test associations of PV in 13 genes with risk of TNBC after accounting for age, ancestry, and personal/family CA history. We analyzed each gene in the full cohort, and in subcohorts defined by self-reported ancestry. Effect sizes are expressed as odds ratios with 95% confidence intervals. Seven genes are not reported in ancestry-stratified analyses due to small numbers of PV carriers with TNBC. Results: From 627,219 individuals referred for multigene panel testing, 115,337 (18.4%) women with personal history of BC were identified, of whom 17,951 (15.6%) reported TNBC. Personal history of TNBC was reported more frequently in women of African ancestry (26.9%) than in women of European (13.9%) or Asian (11.7%) or Latinx ancestry (14.9%). Ancestry-stratified risks of TNBC associated with germline PVs are seen in the Table. Conclusions: While small samples sizes limit some gene-specific analyses, comparable ancestry-specific risks of TNBC were seen across the racial/ethnic groups examined here. [Table: see text]

Simulation modeling as a tool to support clinical guidelines and care for breast cancer prevention and early detection in high-risk women

10525

Background: To evaluate the incremental short- and long-term benefits and harms of primary prevention with risk reducing medication in high-risk women receiving screening mammography. Methods: We adapted an established, validated Cancer Intervention and Surveillance Modeling Network (CISNET) breast cancer discrete event microsimulation model developed to synthesize data the impact of using risk-reducing medication and annual mammography among women with a 3% or higher five-year risk of developing breast cancer. We also examined the effects of supplemental MRI. The model follows a simulated cohort of millions of US women from birth to death. We used large observational and clinical trial data to derive input parameters for cohort-specific birth rates, breast cancer risk, incidence and stage, screening performance, survival by age, stage, and subtype, treatment efficacy, and other cause mortality. Breast cancer risk was modeled based on family history, breast density, age and history of past breast biopsy. We compared two strategies, annual 3D mammography alone vs. annual 3D mammography and a 5-year course of risk reducing medication at various starting ages, and adding MRI to each approach. Outcomes included the benefits of risk-reducing drugs (avoiding breast cancer) and screening (stage, breast cancer death). Harms included drug side effects and screening false positives and overdiagnosis. Sensitivity analysis tested the impact of uncertainty in model inputs and assumptions on results. Results: Compared to mammography alone, adding risk reducing medication could decrease invasive breast cancer incidence by 30%, and breast cancer deaths by 30% (Table). However, due to reduction in breast cancer incidence, risk reducing medication could result in a 3% increase in false positive results; adding MRI increases benefits but also increases false-positive results. Benefits and harms of risk reducing medication and breast cancer screening strategies for women at high-risk of developing breast cancer. Conclusions: Risk-reducing mediation reduces the risk of hormone-receptor positive breast cancer, and combining this with mammography (and/or MRI) improves earlier detection. Additional work is ongoing to incorporate adverse effects of therapy. Simulation modeling can be used to provide individualized data to facilitate discussions about breast cancer prevention and early detection among high-risk women seen in clinical practice.[Table: see text]

National claims data analysis of outcomes of hospitalized cancer patients without COVID-19 infection during versus prior to the COVID-19 pandemic

e18679

Background: There has been growing concern regarding the impact of the COVID-19 pandemic on health care delivery and disruption of care to cancer patients. Reductions in cancer surgeries, delays in administration of life saving chemo and radiation therapies, and lower rates of cancer-related hospitalizations have been reported. While cancer patients with COVID-19 infection have poor hospitalization outcomes, less is known about the outcomes of hospitalized cancer patients without the infection. This study aimed to describe the impact of the COVID-19 pandemic on outcomes of the most common cancer-related hospital admissions for patients without COVID-19 infection at a national level using insurance claims. Given the concern for disruptions in their care, we hypothesized that hospitalized cancer patients may have worse outcomes. Methods: We used the Optum Clinformatics Data Mart, consisting of claims records linked to electronic health records, including an average of 8 million adult Americans per year enrolled for at least 6 months. We identified cancer-related hospitalizations from 02/2018-05/2021 and included patients with at least of one of these cancer types: breast, prostate, bladder, ovarian, cervical, lung, colorectal, esophageal, liver, small intestine, gastric, or gallbladder cancer. Patients with cancer-related hospitalization who had COVID-19 infection were excluded. The main outcome was “severe adverse outcome” and included at least one of the following: mortality during or within 30 days of hospitalization, mechanical ventilation during hospitalization, intensive care unit admission, or discharge to hospice. We used Poisson regression to compare the number of hospitalizations before (2/1/2018-1/30/2020) and during (2/1/2020-5/30/2021) the pandemic and a Chi-squared test to compare the proportion of cancer-related hospitalizations with severe adverse outcomes over that time period in 4-month intervals and across cancer types, gender, (male vs female) and geography (the 9 Census Bureau regions). Results: There were 82,796 cancer-related hospitalizations in the period 2/2018-05/2021. A slightly higher proportion of cancer-related hospitalizations resulted in a severe adverse outcome during the pandemic as compared to prior to the pandemic (41.8% vs 40.9%; p = 0.012). There were no differences by cancer site, gender, or geography. The number of hospitalizations was lower during vs prior to the pandemic (p < 0.0001). Conclusions: The number of cancer-related hospitalizations during the pandemic was lower compared to before the, and a slightly higher proportion of those hospitalized experienced severe adverse outcomes among insured U.S. cancer patients without COVID-19 infection. The lower number of cancer-related hospitalizations during the pandemic warrants further investigation.

Harnessing artificial intelligence to automate delineation of volumetric breast cancers from magnetic resonance imaging to improve tumor characterization

597

Background: Automated breast tumor identification and segmentation in magnetic resonance imaging (MRI) is a difficult and crucial area of study in breast cancer research. Artificial intelligence (AI) models are increasingly being developed for automated localization of lesions in imaging studies to facilitate quantitative assessment of features for improved diagnostic, prognostic and predictive performance. Such models have had success in detecting breast cancers in mammography, ultrasound and CT, but few have achieved three-dimensional (3D) volumetric tumor segmentation from breast MRI. The purpose of this study was to apply two state-of-the-art AI – specifically, deep learning (DL) - algorithms to 3D MRI breast cancer data and identify the higher performing algorithm for precise segmentation of breast tumors. Methods: We evaluated pre-treatment, T1 post-gadolinium contrast enhanced breast MRI from 222 patients with known breast cancers (n = 262). Images were split into training (n = 142), validation (n = 36), and hold-out test (n = 44) datasets. Two DL algorithms, U-Net and VAE-UNet, were trained to classify tumors on the training dataset across 1000 epochs. The output for each is a precise localization and segmentation of each tumor at the pixel level from every MRI image. We evaluated the performance of each algorithm using 5-fold cross-validation and testing on the validation and test sets. We calculated a dice accuracy score for each model as the performance comparison metric. Results: The highest dice accuracy score achieved on the validation dataset by generic U-Net was 83.38%, with an average across 1000 epochs of 62.41%. The highest dice accuracy achieved on the validation dataset by VAE-UNet was 82.62%, with an average across epochs of 61.28%. On our test dataset, the highest dice accuracy score achieved by U-Net was 93.09%, with an average across epochs of 66.31%, and the highest accuracy score for VAE-UNet was 90.98%, with average across epochs of 50.47%. Although U-Net appeared to perform slightly better than VAE-Unet for most cases, there were distinct cases where VAE-UNet outperformed U-Net (dice score up to 59% better than U-Net). Subsequent analysis indicated that VAE-UNet preferentially outperforms U-Net for tumors with low sphericity (p = 0.001). Conclusions: Our results suggest that U-Net is well suited for segmenting breast tumors from breast MRI in most cases, but that VAE-UNet outperforms U-Net when the tumor shapes are less spherical. Our findings could inform the choice of DL algorithms in research and clinical endeavors that rely on accurate breast cancer tumor segmentation. In particular, these two tools could be configured to facilitate tumor assessment from breast MRI in the clinical setting for: breast cancer screening in high-risk patient populations, pre-surgical planning, and monitoring of treatment response.