Association of Germline Genetic Testing Results With Locoregional and Systemic Therapy in Patients With Breast Cancer

Reporting tumor genomic test results to SEER registries via linkages

BACKGROUND

Precision medicine has become a mainstay of cancer care in recent years. The National Cancer Institute (NCI) Surveillance, Epidemiology, and End Results (SEER) Program has been an authoritative source of cancer statistics and data since 1973. However, tumor genomic information has not been adequately captured in the cancer surveillance data, which impedes population-based research on molecular subtypes. To address this, the SEER Program has developed and implemented a centralized process to link SEER registries' tumor cases with genomic test results that are provided by molecular laboratories to the registries.

METHODS

Data linkages were carried out following operating procedures for centralized linkages established by the SEER Program. The linkages used Match*Pro, a probabilistic linkage software, and were facilitated by the registries' trusted third party (an honest broker). The SEER registries provide to NCI limited datasets that undergo preliminary evaluation prior to their release to the research community.

RESULTS

Recently conducted genomic linkages included OncotypeDX Breast Recurrence Score, OncotypeDX Breast Ductal Carcinoma in Situ, OncotypeDX Genomic Prostate Score, Decipher Prostate Genomic Classifier, DecisionDX Uveal Melanoma, DecisionDX Preferentially Expressed Antigen in Melanoma, DecisionDX Melanoma, and germline tests results in Georgia and California SEER registries.

CONCLUSIONS

The linkages of cancer cases from SEER registries with genomic test results obtained from molecular laboratories offer an effective approach for data collection in cancer surveillance. By providing de-identified data to the research community, the NCI's SEER Program enables scientists to investigate numerous research inquiries.

Comparing Cancer Risk Management between Females with Truncating CHEK2 1100delC versus Missense CHEK2 I157T Variants

Breast cancer (BC) risks imparted by CHEK2 c.1100delC ("1100delC") germline pathogenic/likely pathogenic variant (GPV) are 20-30%, compared to CHEK2 c.470T>C ("I157T") GPV with <20%, leading to different breast screening recommendations through MRI. We compared cancer risk management (CRM) across these two GPVs. Study participants were adult females with an 1100delC or I157T GPV drawn from the Inherited Cancer Registry (ICARE) across the United States. Cancer history, clinical characteristics, and CRM were compared using chi-squared tests, t-tests, and logistic regression. Of 150 CHEK2 carriers, 40.7% had BC, with a mean age of 50. Comparing 1100delC and I157T GPVs, there were no differences in rates of (1) breast MRI among those with (65.2% versus 55.6% of 23 and 9; p = 0.612) and without (44.0% versus 44.8% of 50 and 29; p = 0.943) BC; (2) risk-reducing mastectomy among those with (50% versus 38.9% of 46 and 15; p = 0.501) and without (13.8% versus 6.5% of 58 and 31; p = 0.296) BC; and (3) risk-reducing salpingo-oophorectomy among those with (24.2% versus 22.2% of 45 and 18; p = 0.852) and without (17.5% versus 16.7% of 57 and 30; p = 0.918) BC. The results suggest over-screening with breast MRI among CHEK2 I157T GPV carriers and possible overuse of risk-reducing surgeries among CHEK2 carriers.

The Challenges of Lobular Carcinomas from a Surgeon's Point of View

Invasive lobular breast cancer (ILC) presents unique challenges and considerations in the realm of surgical management. Characterized by its distinct histological features, including the loss of E-cadherin expression and dys-cohesive growth pattern, ILC often poses diagnostic and therapeutic dilemmas for clinicians. This abstract explores the surgical landscape of ILC, focusing on its epidemiology, clinical presentation, diagnostic modalities, and surgical interventions. Emphasizing the importance of individualized treatment strategies, this narrative delves into the nuances of surgical decision-making, including the role of breast-conserving surgery versus mastectomy, axillary staging, and the significance of margin status. Additionally, advancements in surgical techniques, such as oncoplastic approaches and sentinel lymph node biopsy, are examined in the context of optimizing oncologic outcomes and preserving cosmesis. Through a comprehensive review of current literature and clinical guidelines, this overview aims to provide a nuanced understanding of the surgical considerations inherent to the management of invasive lobular breast cancer.

Universal Germline-Genetic Testing for Breast Cancer: Implementation in a Rural Practice and Impact on Shared Decision-Making

BACKGROUND

Whereas the National Comprehensive Cancer Network (NCCN) criteria restrict germline-genetic testing (GGT) to a subset of breast cancer (BC) patients, the American Society of Breast Surgeons recommends universal GGT. Although the yield of pathogenic germline variants (PGV) in unselected BC patients has been studied, the practicality and utility of incorporating universal GGT into routine cancer care in community and rural settings is understudied. This study reports real-world implementation of universal GGT for patients with breast cancer and genetics-informed, treatment decision-making in a rural, community practice with limited resources.

METHODS

From 2019 to 2022, all patients with breast cancer at a small, rural hospital were offered GGT, using a genetics-extender model. Statistical analyses included Fisher's exact test, t-tests, and calculation of odds ratios. Significance was set at p < 0.05.

RESULTS

Of 210 patients with breast cancer who were offered GGT, 192 (91.4%) underwent testing with 104 (54.2%) in-criteria (IC) and 88 (45.8%) out-of-criteria (OOC) with NCCN guidelines. Pathogenic germline variants were identified in 25 patients (13.0%), with PGV frequencies of 15 of 104 (14.4%) in IC and ten of 88 (11.4%) in OOC patients (p = 0.495). GGT informed treatment for 129 of 185 (69.7%) patients.

CONCLUSIONS

Universal GGT was successfully implemented in a rural, community practice with > 90% uptake. Treatment was enhanced or de-escalated in those with and without clinically actionable PGVs, respectively. Universal GGT for patients with breast cancer is feasible within rural populations, enabling optimization of clinical care to patients' genetic profile, and may reduce unnecessary healthcare, resource utilization.

Applying the framework for developing and evaluating complex interventions to increase family communication about hereditary cancer

Objective

Evaluate an intervention to increase family communication (FC) of positive hereditary cancer test results using the Framework for Developing and Evaluating Complex Interventions (FDECI).

Methods

We developed 'programme theory' during the FDECI development phase by aligning intervention components with behavior change techniques (BCTs) and theoretical factors expected to improve FC. During the feasibility phase, we obtained feedback from 12 stakeholder interviews.

Results

Intervention components aligned with a total of 14 unique BCTs for which prior evidence links the BCT to theoretical factors that influence behavior change. Constructive stakeholder feedback included: more information desired, rewording to support autonomy by highlighting options, and improvements to navigation, visuals, and audio. Positive comments included: comprehensiveness of materials, modeling of conversations, and usefulness of the materials for helping a person prepare to share positive test results.

Conclusion

The first FDECI phases were helpful for improving the intervention and planning our ongoing effectiveness and future implementation phases.

Innovation

Our application of the FDECI is novel, including plans to test our 'programme theory' using coincidence analysis (CNA) to determine who accesses which intervention materials, how utilizing certain materials impact the aligned theoretical factors, and whether these in turn make a difference in the behavioral outcome.

Association of Moderate-Risk Breast Cancer Genes with Contralateral Prophylactic Mastectomy and Bilateral Disease

BACKGROUND

The impact of ATM, CHEK2, and PALB2, the three most prevalent moderate-risk breast cancer genes, on surgical decision making is not well known.

METHODS

Our retrospective study included patients with resectable non-metastatic breast cancer who underwent multigene panel testing between July 2014 and January 2020 with at least one genetic alteration (pathogenic or variant of uncertain significance [VUS] in ATM [n = 49], CHEK [n = 57], or PALB2 [n = 27]). Our objectives were to determine the rate of contralateral prophylactic mastectomy (CPM) and the rate of bilateral breast cancer. Univariable analyses (UVA) and multivariable analyses (MVA) were performed to identify factors associated with CPM and bilateral breast cancer.

RESULTS

The rate of CPM was 39% (n = 49/127), with 54% (n = 25/46) of patients with a pathogenic mutation and 30% (n = 24/81) of patients with a VUS choosing CPM. On MVA, premenopausal status (odds ratio [OR] 3.46) and a pathogenic alteration (OR 3.01) were associated with increased use of CPM. Bilateral disease was noted in 16% (n = 22/138). Patients with pathogenic mutations had a 22% (n = 11/51) incidence of bilateral breast cancer, while patients with VUS had a 13% (n = 11/87) incidence, although this was not statistically significant on UVA or MVA. On MVA, premenopausal status was associated with a decreased risk of bilateral disease (OR 0.33, p = 0.022). During follow-up, a breast cancer event occurred in 16% (n = 22/138).

CONCLUSIONS

Our study identified a high rate of CPM among those with ATM, CHEK2, and PALB2 alterations, including VUS. Further studies are needed to clarify reasons for CPM among patients with moderate-risk alterations.

Management of individuals with germline pathogenic/likely pathogenic variants in CHEK2: A clinical practice resource of the American College of Medical Genetics and Genomics (ACMG)

PURPOSE

Although the role of CHEK2 germline pathogenic variants in cancer predisposition is well known, resources for managing CHEK2 heterozygotes in clinical practice are limited.

METHODS

An international workgroup developed guidance on clinical management of CHEK2 heterozygotes informed by peer-reviewed publications from PubMed.

RESULTS

Although CHEK2 is considered a moderate penetrance gene, cancer risks may be considered as a continuous variable, which are influenced by family history and other modifiers. Consequently, early cancer detection and prevention for CHEK2 heterozygotes should be guided by personalized risk estimates. Such estimates may result in both downgrading lifetime breast cancer risks to those similar to the general population or upgrading lifetime risk to a level at which CHEK2 heterozygotes are offered high-risk breast surveillance according to country-specific guidelines. Risk-reducing mastectomy should be guided by personalized risk estimates and shared decision making. Colorectal and prostate cancer surveillance should be considered based on assessment of family history. For CHEK2 heterozygotes who develop cancer, no specific targeted medical treatment is recommended at this time.

CONCLUSION

Systematic prospective data collection is needed to establish the spectrum of CHEK2-associated cancer risks and to determine yet-unanswered questions, such as the outcomes of surveillance, response to cancer treatment, and survival after cancer diagnosis.

The Role of the Surgeon in the Germline Testing of the Newly Diagnosed Breast Cancer Patient

For patients with newly diagnosed breast cancer, information regarding hereditary predisposition can influence treatment decisions. From a surgical standpoint, patients with known germline mutations may alter decisions of local therapy to reduce the risk of second breast primaries. This information may also be considered in the choice of adjuvant therapies or eligibility for clinical trials. In recent years, the criteria for the consideration of germline testing in patients with breast cancer has expanded. Additionally, studies have shown a similar prevalence of pathogenic mutations in those patients outside of these traditional criteria, prompting calls for genetic testing for all patients with a history of breast cancer. While data confirms the benefit of counseling by certified genetics professionals, the capacity of genetic counselors may no longer meet the needs of these growing numbers of patients. National societies assert that counseling and testing can be performed by providers with training and experience in genetics. Breast surgeons are well positioned to offer this service, as they receive formal genetics training during their fellowship, manage these patients daily in their practices, and are often the first providers to see patients after their cancer diagnosis.

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.

Multigene Panel Testing Yields High Rates of Clinically Actionable Variants Among Patients With Colorectal Cancer

PURPOSE

Whether germline multigene panel testing (MGPT) should be performed in all individuals with colorectal cancer (CRC) remains uncertain. Therefore, we aimed to determine the yield and potential clinical impact of MGPT across a large, diverse CRC cohort.

METHODS

This was a retrospective cohort study of adults with CRC who underwent MGPT of > 10 genes at a commercial laboratory between March 2015 and May 2021. All data were prospectively collected through a single commercial laboratory and retrospectively analyzed.

RESULTS

A total of 34,244 individuals with a history of CRC underwent germline MPGT and were included in the analysis. This cohort was predominantly female (60.7%), White (70.6%), and age 50 years or older (68.9%), with 35.5% also reporting a noncolorectal malignancy. At least one pathogenic/likely pathogenic germline variant (PGV) was found in 4,864 (14.2%), with 3,111 (9.1%) having a PGV associated with increased CRC/polyposis risk and 1,048 (3.1%) having an otherwise clinically actionable PGV. Larger gene panels were not clearly associated with higher yield of clinically actionable PGVs. PGVs were more prevalent in individuals of Ashkenazi Jewish descent (P < .001) and Hispanic ethnicity (P < .001). Across all ages, panel sizes, and races/ethnicities, the rate of clinically actionable PGVs on MGPT was 7.9% or greater. A variant of uncertain significance was identified in 13,094 individuals (38.2%). Identification of a variant of uncertain significance associated with panel size (P < .001) and was lower in individuals of Ashkenazi Jewish descent (P < .001), but higher in Black, Asian, and Hispanic individuals (P < .001).

CONCLUSION

To our knowledge, this is the largest study to date examining MGPT in CRC, demonstrating high rates of clinically actionable variants detected across all age groups, panel sizes, and racial/ethnic groups. This work supports consideration of broadening germline genetic testing criteria for individuals with CRC.

Prophylactic mastectomy and occult malignancy: Surgical and imaging considerations

BACKGROUND

Sentinel node biopsy (SLNB) is not routinely recommended for patients undergoing prophylactic mastectomy (PM), yet omission remains a subject of debate among surgeons. A modern patient cohort was examined to determine occult malignancy (OM) incidence within PM specimens to reinforce current recommendations.

METHODS

All PM performed over a 5-year period were retrospectively identified, including women with unilateral breast cancer who underwent synchronous or delayed contralateral PM or women with elevated cancer risk who underwent bilateral PM.

RESULTS

The study population included 772 patients (598 CPM, 174 BPM) with a total of 39 OM identified: 17 invasive cancers (14 CPM, 3 BPM) and 22 DCIS (19 CPM, 3 BPM). Of the 86 patients for whom SLNB was selectively performed, 1 micrometastasis was identified. In the CPM cohort, risk of OM increased with age, presence of LCIS of either breast, or presence of a non-BRCA high-penetrance gene mutation, while preoperative magnetic resonance imaging was associated with lower likelihood of OM.

CONCLUSIONS

Given the low incidence of invasive OM in this updated series, routine SLNB is of low value for patients undergoing PM. For patients with indeterminate radiographic findings, discordant preoperative biopsies, LCIS, or non-BRCA high-penetrance gene mutations, selective SLNB implementation could be considered.

Clinical Utility of Universal Germline Genetic Testing for Patients With Breast Cancer

IMPORTANCE

National Comprehensive Cancer Network guidelines currently recommend germline testing for high-risk genes in selected patients with breast cancer. The clinical utility of recommending testing all patients with breast cancer with multigene panels is currently under consideration.

OBJECTIVE

To examine the implications of universal testing of patients with breast cancer with respect to clinical decision-making.

DESIGN, SETTING, AND PARTICIPANTS

Patients from a previously reported cohort were assessed as in-criteria or out-of-criteria according to the 2017 guidelines and underwent testing with a multigene germline panel between 2017 to 2018. Patients were women and men aged 18 to 90 years, with a new and/or previous diagnosis of breast cancer who had not undergone either single or multigene testing. Clinicians from 20 community and academic sites documented patient clinical information and changes to clinical recommendations made according to test findings. Association between prevalence of pathogenic or likely pathogenic germline variants and previously unreported clinical features, including scores generated by the BRCAPRO statistical model, was determined. Data were analyzed from April 2020 to May 2022.

EXPOSURE

New and/or previous diagnosis of breast cancer.

MAIN OUTCOMES AND MEASURES

Disease management recommendations that were changed as a result of genetic testing results are reported.

RESULTS

Clinicians were asked to assess changes to clinical management as a result of germline genetic testing for 952 patients. Informative clinician-reported recommendations were provided for 939 (467 in-criteria and 472 out-of-criteria) of the patients with breast cancer (936 [99.7%] female; 702 [74.8%] White; mean [SD] age at initial diagnosis, 57.6 [11.5] years). One or more changes were reported for 31 of 37 (83.8%) in-criteria patients and 23 of 34 (67.6%) out-of-criteria patients with a pathogenic or likely pathogenic variant. Recommendations were changed as a result of testing results for 14 of 22 (63.6%) out-of-criteria patients who had a variant in a breast cancer predisposition gene. Clinicians considered testing beneficial for two-thirds of patients with pathogenic or likely pathogenic variants and for one-third of patients with either negative results or variants of uncertain significance. There was no difference in variant rate between patients meeting the BRCAPRO threshold (≥10%) and those who did not (P = .86, Fisher exact test). No changes to clinical recommendations were made for most patients with negative results (345 of 349 patients [98.9%]) or variants of uncertain significance (492 of 509 patients [96.7%]).

CONCLUSIONS AND RELEVANCE

In this cohort study, germline genetic testing was used by clinicians to direct treatment for most out-of-criteria patients with breast cancer with pathogenic or likely pathogenic germline variants, including those with moderate-risk variants. Universal germline testing informs clinical decision-making and provides access to targeted treatments and clinical trials for all patients with breast cancer.

Male Breast Cancer Patient and Surgeon Experience: The Male WhySurg Study

BACKGROUND

Little is known about the experience of the male breast cancer patient. Mastectomy is often offered despite evidence that breast-conserving surgery (BCS) provides similar outcomes.

METHODS

Two concurrent online surveys were distributed from August to October 2020 via social media to male breast cancer (MBC) patients and by email to American Society of Breast Surgeon members. The MBC patients were asked their opinions about their surgery, and the surgeons were asked to provide surgical recommendations for MBC patients.

RESULTS

The survey involved 63 MBC patients with a mean age of 62 years (range, 31-79 years). Five MBC patients (7.9 %) stated that their surgeon recommended BCS, but 54 (85.7 %) of the patients underwent unilateral, and 8 (12.7 %) underwent bilateral mastectomy. Most of the patients (n = 60, 96.8 %) had no reconstruction. One third of the patients (n = 21, 33.3 %) felt somewhat or very uncomfortable with their appearance after surgery. The response rate was 16.5 % for the surgeons. Of the 438 surgeons who answered the survey, 298 (73.3 %) were female, 215 (51.7 %) were fellowship-trained, and 244 (58.9 %) had been practicing for 16 years or longer. More than half of surgeons (n = 259, 59.1 %) routinely offered BCS to eligible men, and 180 (41.3 %) stated they had performed BCS on a man with breast cancer. Whereas 89 (20.8 %) of the surgeons stated that they routinely offer reconstruction to MBC patients, 87 (20.3 %) said they do not offer reconstruction, 96 (22.4 %) said they offer it only if the patient requests it, and 157 (36.6 %) said they never consider it as an option.

CONCLUSIONS

The study found discordance between MBC patients' satisfaction with their surgery and surgeon recommendations and experience. These data present an opportunity to optimize the MBC patient experience.

Influence of germline test results on surgical decision making in women with invasive breast cancer

BACKGROUND

While therapeutic mastectomy with contralateral prophylactic mastectomy (TM+CPM) and/or bilateral salpingo-oophorectomy (BSO) are recommended for women with pathogenic variants (PV) in some cancer predisposition genes, evidence for the utility of these surgeries for women with PV in other genes currently is insufficient. In conjunction, current guidelines recommend that clinical management should not be influenced by a return of a variant of uncertain significance (VUS). Return of germline test results may, however, influence surgical decision making regardless of current guidelines. We thus evaluated surgical choices amongst a cohort of women with invasive breast cancer who underwent clinical genetic testing.

METHODS

Germline test results and all surgical procedures were extracted for women who had unilateral invasive breast cancer and had clinical testing before definitive surgery (n = 591). Results were classified as pathogenic/likely pathogenic (PV, 17.1%), VUS (19.5%) or benign/likely benign (63.4%). Data were analyzed using chi-square tests with p<0.05 defining significance.

RESULTS

Rates of TM+CPM and BSO were not significantly different for women with VUS compared to those with benign findings. Rates of TM+CPM were significantly higher for women with PV in BRCA1 and BRCA2, PALB2, PTEN and TP53, as well in genes with insufficient data to recommend risk-reducing mastectomy. Rates of BSO were significantly higher in women with PV in BRCA1 and BRCA2, PALB2, PTEN and TP53 and BRIP1, RAD51C and RAD51D compared to those with benign findings.

CONCLUSION

Overall, surgical choices for women with a VUS were more similar to those from women with benign variants than to those with PV, however, in the group with PV in genes for which insufficient evidence exists for the benefit of risk-reducing mastectomy, rates of TM+CPM were high. Thus, while the management of women with VUS is in agreement with ACMG guidelines, patients with mutations in other cancer genes demonstrate a preference for more aggressive breast surgeries.

Harnessing the DNA Repair Pathway in Breast Cancer: Germline Mutations/Polymorphisms in Breast Radiation

Molecular profiling facilitates opportunities for personalization of breast cancer management. Increasing availability of germline and somatic sequencing provides insight into predictors of treatment efficacy and treatment tolerance of patients with breast cancer. The presence of pathologic mutations can guide patient selection for breast conserving surgery vs mastectomy. However, our understanding of the interplay between genetic variants and radiotherapy responses and side effects remains incomplete. Here we review the available data on germline mutations and polymorphisms in breast cancer. We also outline their association with treatment tolerance, locoregional outcomes, and ongoing efforts to transform these insights into more effective treatment strategies in combination with radiotherapy.

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.

Association Between Genetic Testing for Hereditary Breast Cancer and Contralateral Prophylactic Mastectomy Among Multiethnic Women Diagnosed With Early-Stage Breast Cancer

PURPOSE

Increasing usage of multigene panel testing has identified more patients with pathogenic or likely pathogenic (P or LP) variants in low-moderate penetrance genes or variants of uncertain significance (VUS). Our study evaluates the association between genetic test results and contralateral prophylactic mastectomy (CPM) among patients with breast cancer.

METHODS

We conducted a retrospective cohort study among women diagnosed with unilateral stage 0-III breast cancer between 2013 and 2020 who underwent genetic testing. We examined whether genetic test results were associated with CPM using multivariable logistic regression models.

RESULTS

Among 707 racially or ethnically diverse women, most had benign or likely benign (B or LB) variants, whereas 12.5% had P or LP and 17.9% had VUS. Racial or ethnic minorities were twice as likely to receive VUS. Patients with P or LP variants had higher CPM rates than VUS or B or LB (64.8% v 25.8% v 25.9%), and highest among women with P or LP variants in high-penetrance genes (74.6%). On multivariable analysis, P or LP compared with B or LB variants were significantly associated with CPM (odds ratio = 4.24; 95% CI, 2.48 to 7.26).

CONCLUSION

Women with P or LP variants on genetic testing were over four times more likely to undergo CPM than B or LB. Those with VUS had similar CPM rates as B or LB. Our findings suggest appropriate genetic counseling and communication of cancer risk to multiethnic breast cancer survivors.

DrABC: deep learning accurately predicts germline pathogenic mutation status in breast cancer patients based on phenotype data

Background

Identifying breast cancer patients with DNA repair pathway-related germline pathogenic variants (GPVs) is important for effectively employing systemic treatment strategies and risk-reducing interventions. However, current criteria and risk prediction models for prioritizing genetic testing among breast cancer patients do not meet the demands of clinical practice due to insufficient accuracy.

Methods

The study population comprised 3041 breast cancer patients enrolled from seven hospitals between October 2017 and 11 August 2019, who underwent germline genetic testing of 50 cancer predisposition genes (CPGs). Associations among GPVs in different CPGs and endophenotypes were evaluated using a case-control analysis. A phenotype-based GPV risk prediction model named DNA-repair Associated Breast Cancer (DrABC) was developed based on hierarchical neural network architecture and validated in an independent multicenter cohort. The predictive performance of DrABC was compared with currently used models including BRCAPRO, BOADICEA, Myriad, PENN II, and the NCCN criteria.

Results

In total, 332 (11.3%) patients harbored GPVs in CPGs, including 134 (4.6%) in BRCA2, 131 (4.5%) in BRCA1, 33 (1.1%) in PALB2, and 37 (1.3%) in other CPGs. GPVs in CPGs were associated with distinct endophenotypes including the age at diagnosis, cancer history, family cancer history, and pathological characteristics. We developed a DrABC model to predict the risk of GPV carrier status in BRCA1/2 and other important CPGs. In predicting GPVs in BRCA1/2, the performance of DrABC (AUC = 0.79 [95% CI, 0.74–0.85], sensitivity = 82.1%, specificity = 63.1% in the independent validation cohort) was better than that of previous models (AUC range = 0.57–0.70). In predicting GPVs in any CPG, DrABC (AUC = 0.74 [95% CI, 0.69–0.79], sensitivity = 83.8%, specificity = 51.3% in the independent validation cohort) was also superior to previous models in their current versions (AUC range = 0.55–0.65). After training these previous models with the Chinese-specific dataset, DrABC still outperformed all other methods except for BOADICEA, which was the only previous model with the inclusion of pathological features. The DrABC model also showed higher sensitivity and specificity than the NCCN criteria in the multi-center validation cohort (83.8% and 51.3% vs. 78.8% and 31.2%, respectively, in predicting GPVs in any CPG). The DrABC model implementation is available online at http://gifts.bio-data.cn/.

Conclusions

By considering the distinct endophenotypes associated with different CPGs in breast cancer patients, a phenotype-driven prediction model based on hierarchical neural network architecture was created for identification of hereditary breast cancer. The model achieved superior performance in identifying GPV carriers among Chinese breast cancer patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13073-022-01027-9.

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

PURPOSE

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

METHODS AND MATERIALS

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

RESULTS

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

CONCLUSIONS

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

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

PURPOSE

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

METHODS AND MATERIALS

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

RESULTS

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

CONCLUSION

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

An overview of genetic services delivery for hereditary breast cancer

Breast cancer is the most common cancer diagnosed in women worldwide, with approximately 5-10% of cases attributed to high penetrance hereditary breast cancer (HBC) genes. The tremendous advances in precision oncology have broadened indications for germline genetic testing to guide both systemic and surgical treatment, with increasing demand for cancer genetic services. The HBC continuum of care includes (1) identification, access, and uptake of genetic counseling and testing; (2) the delivery of genetic counseling and testing services; and (3) initiation of guideline-adherent follow-up care and family communication of results. Challenges to delivering care on the HBC care continuum include factors such as access to services, cost, discrimination and bias, and lack of education and awareness, which can be mitigated through implementing a multi-level approach. This includes strategies such as increasing awareness and utilization of genetic counseling and testing, developing new methods to meet the growing demand for genetic services, and improving the uptake of follow-up care by increasing patient and provider awareness of the management recommendations.

IMProving care After inherited Cancer Testing (IMPACT) study: protocol of a randomized trial evaluating the efficacy of two interventions designed to improve cancer risk management and family communication of genetic test results

BACKGROUND

Implementing genetic testing for inherited cancer predisposition into routine clinical care offers a tremendous opportunity for cancer prevention and early detection. However, genetic testing itself does not improve outcomes; rather, outcomes depend on implemented follow-up care. The IMPACT study is a hybrid type I randomized effectiveness-implementation trial to simultaneously evaluate the effectiveness of two interventions for individuals with inherited cancer predisposition focused on: 1) increasing family communication (FC) of genetic test results; and 2) improving engagement with guideline-based cancer risk management (CRM).

METHODS

This prospective study will recruit a racially, geographically, and socioeconomically diverse population of individuals with a documented pathogenic/likely pathogenic (P/LP) variant in an inherited cancer gene. Eligible participants will be asked to complete an initial trial survey and randomly assigned to one of three arms: A) GeneSHARE, a website designed to increase FC of genetic test results; B) My Gene Counsel's Living Lab Report, a digital tool designed to improve understanding of genetic test results and next steps, including CRM guidelines; or C) a control arm in which participants continue receiving standard care. Follow-up surveys will be conducted at 1, 3, and 12 months following randomization. These surveys include single-item measures, scales, and indices related to: 1) FC and CRM behaviors and behavioral factors following the COM-B theoretical framework (i.e., capability, opportunity, and motivation); 2) implementation outcomes (i.e., acceptability, appropriateness, exposure, and reach); and 3) other contextual factors (i.e., sociodemographic and clinical factors, and uncertainty, distress, and positive aspects of genetic test results). The primary outcomes are an increase in FC of genetic test results (Arm A) and improved engagement with guideline-based CRM without overtreatment or undertreatment (Arm B) by the 12-month follow-up survey.

DISCUSSION

Our interventions are designed to shift the paradigm by which individuals with P/LP variants in inherited cancer genes are provided with information to enhance FC of genetic test results and engagement with guideline-based CRM. The information gathered through evaluating the effectiveness and implementation of these real-world approaches is needed to modify and scale up adaptive, stepped interventions that have the potential to maximize FC and CRM.

TRIAL REGISTRATION

This study is registered at Clinicaltrials.gov (NCT04763915, date registered: February 21, 2021).

PROTOCOL VERSION

September 17th, 2021 Amendment Number 04.

Time Trends in Receipt of Germline Genetic Testing and Results for Women Diagnosed With Breast Cancer or Ovarian Cancer, 2012-2019

PURPOSE

Genetic testing is important for breast and ovarian cancer risk reduction and treatment, yet little is known about its evolving use.

METHODS

SEER records of women of age ≥ 20 years diagnosed with breast or ovarian cancer from 2013 to 2017 in California or Georgia were linked to the results of clinical germline testing through 2019. We measured testing trends, rates of variants of uncertain significance (VUS), and pathogenic variants (PVs).

RESULTS

One quarter (25.2%) of 187,535 patients with breast cancer and one third (34.3%) of 14,689 patients with ovarian cancer were tested; annually, testing increased by 2%, whereas the number of genes tested increased by 28%. The prevalence of test results by gene category for breast cancer cases in 2017 were BRCA1/2, PVs 5.2%, and VUS 0.8%; breast cancer-associated genes or ovarian cancer-associated genes (ATM, BARD1, BRIP1, CDH1, CHEK2, EPCAM, MLH1, MSH2, MSH6, NBN, NF1, PALB2, PMS2, PTEN, RAD51C, RAD51D, STK11, and TP53), PVs 3.7%, and VUS 12.0%; other actionable genes (APC, BMPR1A, MEN1, MUTYH, NF2, RB1, RET, SDHAF2, SDHB, SDHC, SDHD, SMAD4, TSC1, TSC2, and VHL) PVs 0.6%, and VUS 0.5%; and other genes, PVs 0.3%, and VUS 2.6%. For ovarian cancer cases in 2017, the prevalence of test results were BRCA1/2, PVs 11.0%, and VUS 0.9%; breast or ovarian genes, PVs 4.0%, and VUS 12.6%; other actionable genes, PVs 0.7%, and VUS 0.4%; and other genes, PVs 0.3%, and VUS 0.6%. VUS rates doubled over time (2013 diagnoses: 11.2%; 2017 diagnoses: 26.8%), particularly for racial or ethnic minorities (47.8% Asian and 46.0% Black, v 24.6% non-Hispanic White patients; P < .001).

CONCLUSION

A testing gap persists for patients with ovarian cancer (34.3% tested v nearly all recommended), whereas adding more genes widened a racial or ethnic gap in VUS results. Most PVs were in 20 breast cancer-associated genes or ovarian cancer-associated genes; testing other genes yielded mostly VUS. Quality improvement should focus on testing indicated patients rather than adding more genes.

CHEK2 Pathogenic Variants in Greek Breast Cancer Patients: Evidence for Strong Associations with Estrogen Receptor Positivity, Overuse of Risk-Reducing Procedures and Population Founder Effects

Simple Summary

CHEK2 germline pathogenic variants are identified at a relatively high frequency among hereditary breast cancer cases and are known to be associated with intermediate breast cancer risk i.e., 2–2.5-fold increase, compared to the general population. Histopathological characteristics and clinical outcomes of breast cancer patients who are CHEK2 carriers have not been thoroughly investigated. We have therefore sought to determine the CHEK2 variant spectrum and identify variants with possible founder effect, while investigating the clinicopathological features and outcomes of Greek patients who were CHEK2 carriers. Three variants have been identified as Greek founders. The vast majority of CHEK2-associated breast tumors were hormone receptor positive, underlying a possible benefit from chemoprophylaxis with tamoxifen. A trend for longer survival was observed in patients that underwent mastectomy and received hormone-therapy. Nearly half of patients underwent a risk-reducing surgery, which was not mandated according to current guidelines or relevant risks associated with CHEK2.

Abstract

CHEK2 germline pathogenic variants predispose to breast cancer and possibly to other malignancies, with their spectrum and frequency being variable among populations. Τhe majority of CHEK2-associated breast tumors are hormone receptor positive; however, relevant clinical outcomes are not well defined. Herein, we illustrate the histopathological characteristics and clinical outcomes of 52 Greek breast cancer patients who are CHEK2 carriers. Genetic analysis was performed by Sanger/massively parallel sequencing, followed by MLPA. Subsequent haplotype analysis investigated possible founder effects. Blood relatives were offered cascade testing. CHEK2 variant spectrum was characterized by variability, while influenced by founder effects. The majority of carriers, i.e., 60.8%, were diagnosed with breast cancer before the age of 45. Notably, 91.5% of breast tumors were hormone receptor positive. Hormone therapy and mastectomy at diagnosis seem to have a positive trend on overall survival, after a median follow-up of 9.5 years. Remarkably, 41.9% of patients underwent risk-reducing surgery, one third of which involved salpingo-oophorectomy. Nearly half of families responded to cascade testing. Our data highlight the need for guideline-adherent choices, based on the evidence that CHEK2 carriers are at moderate risk for breast cancer and no risk for ovarian cancer, while underscore the possible role of chemoprevention with tamoxifen.

Study on <em>CCDC69</em> interfering with the prognosis of patients with breast cancer through PPAR signal pathway

Coiled-coil domain-containing protein 69 (CCDC69) is a novel gene and limited knowledge in known in breast cancer. In the present study, we aimed to explore the relationship between CCDC69 and breast cancer, demonstrate the clinicopathological significance and prognostic role of CCDC69 in breast cancer, and analyze the possible mechanism of CCDC69 affecting the prognosis of breast cancer. First, from GEO database, TIMER, GEPIA, and OncoLnc, we select CCDC69 as the potential gene which closely involved in breast cancer progression. Next, by real-time PCR detection, the expression of CCDC69 in breast cancer tissue was notably lower than that in normal breast tissues (p=0.0002). In addition, our immunohistochemistry (IHC) indicated that the positive expression rate of CCDC69 in the triple-negative breast cancer (TNBC) was lower than that in the non-TNBC (p=0.0362), and it was negatively correlated with the expression of Ki67 (p=0.001). Further enrichment analysis of CCDC69 and the similar genes performed on FunRich3.1.3 revealed that these genes were significantly associated with fat differentiation, and most of them were related to peroxisome proliferator-activated receptor (PPAR) signal pathway. Collectively, our findings suggest that CCDC69 is down regulated in breast cancer tissue especially in TNBC which has higher malignant grade and poorer clinical prognosis.

Predicted Chemotherapy Benefit for Breast Cancer Patients With Germline Pathogenic Variants in Cancer Susceptibility Genes

Breast cancer patients increasingly undergo genetic testing. To examine chemotherapy indications for germline pathogenic variant (PV) carriers, we linked results of germline testing to Georgia and California Surveillance, Epidemiology, and End Results registry records, including 21-gene recurrence score (RS) results, for breast cancer patients diagnosed in 2013-2017. All statistical tests were 2-sided. Patients (N=37 349) had RS results of whom 714 had BRCA1, BRCA2, CHEK2, ATM, PALB2, or Lynch syndrome (MLH1, MSH2, MSH6, PMS2) PVs. For women aged 50 years or older at breast cancer diagnosis, RS often exceeded the chemotherapy benefit threshold (≥26) with BRCA1 (71.7% vs 14.4% with none; P <.001), PALB2 (37.1%; P = .001), and BRCA2 (44.3%; P < .001) PVs. Results were similar for women diagnosed at younger than 50 years of age. PVs in BRCA1, but not BRCA2, PALB2, ATM, CHEK2, or Lynch syndrome genes, were associated with elevated RS on multivariable analysis (P < .001). Results may inform RS testing decisions in breast cancer patients with PVs.

Clinicopathological Features and Outcomes in Individuals with Breast Cancer and ATM, CHEK2, or PALB2 Mutations

INTRODUCTION

The moderate-penetrance germline mutations ATM, CHEK2, and PALB2 are implicated in an increased risk of the development of breast cancer. Whether these mutations provide clinical utility to guide treatment strategies and prognosis remains unknown.

METHODS

A retrospective case-control study from a tertiary institution compared patients with stage 0-III breast cancer, and positive for ATM, CHEK2, or PALB2 mutations, with a matched cohort selected by randomization and negative for mutations. Data acquisition included demographics, histopathologic, treatment, and clinical outcome variables.

RESULTS

A total of 145 patients with breast cancer (144 female and 1 male) were analyzed-74 mutation-positive patients (24 ATM, 26 CHEK2, 24 PALB2) and 71 mutation-negative patients. Mutation-positive patients compared with mutation-negative patients had increased family history of breast cancer (79.7 vs. 52.9%, p < 0.001) and tumor size > 2.0 cm (63.1% vs. 42.3%, p = 0.015). Patients with prior knowledge of mutational status were more likely to proceed with total mastectomy and prophylactic mastectomy (74.5% vs. 25.5%, p < 0.02; and 65.5% vs. 34.5%, p < 0.001, respectively). The unadjusted recurrence rate was higher in mutation-positive patients compared with mutation-negative patients (24.3 vs. 8.5%, p = 0.01), although mutation status was not predictive for recurrence in Cox regression analysis.

CONCLUSIONS

Patients positive for ATM, CHEK2, or PALB2 mutations had increased tumor size and were more likely to undergo extensive surgeries. Mutation status was not predictive of recurrence, although this lack of effect may have been mitigated by lower rates of recurrence in those who pursued total mastectomy. Further studies are needed to confirm these findings.