Breast-cancer risk in families with mutations in PALB2

Copper metabolism-related signature for prognosis prediction and MMP13 served as malignant factor for breast cancer

Objectives

To comprehensively analyze the copper metabolism in Breast cancer, we established a prognostic signature for breast cancer (BC) related to copper metabolism.

Methods

Copper metabolism-related genes were sourced from previous literatures and were selected by the Univariate Cox regression. Cu-enrichment scores were calculated via ssGSEA. Differentially expressed genes were identified with limma between high and low Cu-enrichment scores group, then we used the Random Survival Forest and LASSO to build the CuScore for BC. Kaplan-Meier analysis, ROC curves, and Cox regression were used to evaluate CuScore. Genomic mutations were analyzed with GISTIC. Immune cells were examined using ESTIMATE, ssGSEA and TIMER. Enrichment analysis used clusterProfiler and GSVA. The GDSC database and oncoPredict package analyzed chemotherapeutic sensitivity. MMP13 was selected for in vitro assays.

Results

Four copper metabolism-related genes (UBE2D2, SLC31A1, ATP7A, and MAPK1) with prognostic value were identified. Higher expression levels of these genes were associated with higher Cu-enrichment scores, a factor of malignancy in breast cancer. Among 115 differentially expressed genes, 19 prognostic genes were identified, with three (CEACAM5, MMP13, and CRISP3) highlighted by Random Survival Forest and LASSO. Higher CuScores correlated with worse prognoses and were effective in predicting breast cancer outcomes. CuScore and metastasis were independent prognostic factors. Tumor-infiltrating immune cells were associated with lower CuScores. GO-GSEA analysis indicated six immune-related pathways might be regulated by CuScore. Patients with higher CuScores had lower TMB and were more sensitive to Sapitinib and LCL161, while those with lower CuScores might respond better to anti-PD1 therapy. High MMP13 expression in breast cancer was linked to malignancy, affecting cell proliferation and migration.

Conclusion

The identified copper metabolism-related gene signature has the potential to predict prognosis and guide clinical treatment for BC. Among these genes, MMP13 may act as a malignant factor in BC.

Genetics of prostate cancer: a review of latest evidence

Prostate cancer (PrCa) is a largely heritable and polygenic disease. It is the most common cancer in people with prostates (PwPs) in Europe and the USA, including in PwPs of African descent. In the UK in 2020, 52% of all cancers were diagnosed at stage I or II. The National Health Service (NHS) long-term plan is to increase this to 75% by 2028, to reduce absolute incidence of late-stage disease. In the absence of a UK PrCa screening programme, we should explore how to identify those at increased risk of clinically significant PrCa.Incorporating genomics into the PrCa screening, diagnostic and treatment pathway has huge potential for transforming patient care. Genomics can increase efficiency of PrCa screening by focusing on those with genetic predisposition to cancer-which when combined with risk factors such as age and ethnicity, can be used for risk stratification in risk-based screening (RBS) programmes. The goal of RBS is to facilitate early diagnosis of clinically significant PrCa and reduce overdiagnosis/overtreatment in those unlikely to experience PrCa-related symptoms in their lifetime. Genetic testing can guide PrCa management, by identifying those at risk of lethal PrCa and enabling access to novel targeted therapies.PrCa is curable if diagnosed below stage III when most people do not experience symptoms. RBS using genetic profiling could be key here if we could show better survival outcomes (or reduction in cancer-specific mortality accounting for lead-time bias), in addition to more cost efficiency than age-based screening alone. Furthermore, PrCa outcomes in underserved communities could be optimised if genetic testing was accessible, minimising health disparities.

Exploring pathogenic SNPs and estrogen receptor alpha interactions in breast cancer: An in silico approach

The estrogen receptor 1 gene (ESR1) plays a crucial role in breast and mammary development in humans. Alterations such as gene amplification, genomic rearrangements, and missense mutations in the ESR1 gene are reported to increase the risk of breast cancer in humans. The purpose of this study is to analyze the missense mutations and molecular modeling of ESR1, focusing on the pathogenic SNP H516N, for a better understanding of disease risk and future benefits for therapeutic benefits. This SNP was selected based on its location in the binding pocket of ESR1 and its predicted impact on drug binding. The in silico analysis was performed by applying various computational approaches to identify highly pathogenic SNPs in the binding pocket of ESR1. The effect of the SNP was explored through docking and intra-molecular interaction studies. All SNPs in ESR1 were identified followed by the identification of the highly pathogenic variant located in the binding pocket of ESR1. The mutant model of the pathogenic SNP H516N was generated, and hydroxytamoxifen was docked with the wild-type and the mutant model. The mutant model lost the formation of stable hydrogen bonds with the active site residues and hydroxytamoxifen, which may result in reduced binding affinity and therefore, will predict the patient's response to estrogenic inhibitors.

Multigenic panels in breast cancer: Clinical utility and management of patients with pathogenic variants other than BRCA1/2

Multigene panels can analyze high and moderate/intermediate penetrance genes that predispose to breast cancer (BC), providing an opportunity to identify at-risk individuals within affected families. However, considering the complexity of different pathogenic variants and correlated clinical manifestations, a multidisciplinary team is needed to effectively manage BC. A classification of pathogenic variants included in multigene panels was presented in this narrative review to evaluate their clinical utility in BC. Clinical management was discussed for each category and focused on BC, including available evidence regarding the multidisciplinary and integrated management of patients with BC. The integration of both genetic testing and counseling is required for customized decisions in therapeutic strategies and preventative initiatives, as well as for a defined multidisciplinary approach, considering the continuous evolution of guidelines and research in the field.

Impact of Molecular Profiling on Therapy Management in Breast Cancer

Breast cancer (BC) remains the most prevalent cancer among women and the leading cause of cancer-related mortality worldwide. The heterogeneity of BC in terms of histopathological features, genetic polymorphisms, and response to therapies necessitates a personalized approach to treatment. This review focuses on the impact of molecular profiling on therapy management in breast cancer, emphasizing recent advancements in next-generation sequencing (NGS) and liquid biopsies. These technologies enable the identification of specific molecular subtypes and the detection of blood-based biomarkers such as circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), and tumor-educated platelets (TEPs). The integration of molecular profiling with traditional clinical and pathological data allows for more tailored and effective treatment strategies, improving patient outcomes. This review also discusses the current challenges and prospects of implementing personalized cancer therapy, highlighting the potential of molecular profiling to revolutionize BC management through more precise prognostic and therapeutic interventions.

Clinical Impact of Constitutional Genomic Testing on Current Breast Cancer Care

The most commonly diagnosed cancer in women worldwide is cancer of the breast. Up to 20% of familial cases are attributable to pathogenic mutations in high-penetrance (BReast CAncer gene 1 [BRCA1], BRCA2, tumor protein p53 [TP53], partner and localizer of breast cancer 2 [PALB2]) or moderate-penetrance (checkpoint kinase 2 [CHEK2], Ataxia-telangiectasia mutated [ATM], RAD51C, RAD51D) breast-cancer-predisposing genes. Most of the breast-cancer-predisposing genes are involved in DNA damage repair via homologous recombination pathways. Understanding these pathways can facilitate the development of risk-reducing and therapeutic strategies. The number of breast cancer patients undergoing testing for pathogenic mutations in these genes is rapidly increasing due to various factors. Advances in multigene panel testing have led to increased detection of pathogenic mutation carriers at high risk for developing breast cancer and contralateral breast cancer. However, the lack of long-term clinical outcome data and incomplete understanding of variants, particularly for moderate-risk genes limits clinical application. In this review, we have summarized the key functions, risks, and prognosis of breast-cancer-predisposing genes listed in the National Health Service (NHS) England National Genomic Test Directory for inherited breast cancer and provide an update on current management implications including surgery, radiotherapy, systemic treatments, and post-treatment surveillance.

Using polygenic risk modification to improve breast cancer prevention: study protocol for the PRiMo multicentre randomised controlled trial

INTRODUCTION

Established personal and familial risk factors contribute collectively to a woman's risk of breast or ovarian cancer. Existing clinical services offer genetic testing for pathogenic variants in high-risk genes to investigate these risks but recent information on the role of common genomic variants, in the form of a Polygenic Risk Score (PRS), has provided the potential to further personalise breast and ovarian cancer risk assessment. Data from cohort studies support the potential of an integrated risk assessment to improve targeted risk management but experience of this approach in clinical practice is limited.

METHODS AND ANALYSIS

The polygenic risk modification trial is an Australian multicentre prospective randomised controlled trial of integrated risk assessment including personal and family risk factors with inclusion of breast and ovarian PRS vs standard care. The study will enrol women, unaffected by cancer, undergoing predictive testing at a familial cancer clinic for a pathogenic variant in a known breast cancer (BC) or ovarian cancer (OC) predisposition gene (BRCA1, BRCA2, PALB2, CHEK2, ATM, RAD51C, RAD51D). Array-based genotyping will be used to generate breast cancer (313 SNP) and ovarian cancer (36 SNP) PRS. A suite of materials has been developed for the trial including an online portal for patient consent and questionnaires, and a clinician education programme to train healthcare providers in the use of integrated risk assessment. Long-term follow-up will evaluate differences in the assessed risk and management advice, patient risk management intentions and adherence, patient-reported experience and outcomes, and the health service implications of personalised risk assessment.

ETHICS AND DISSEMINATION

This study has been approved by the Human Research Ethics Committee of Peter MacCallum Cancer Centre and at all participating centres. Study findings will be disseminated via peer-reviewed publications and conference presentations, and directly to participants.

TRIAL REGISTRATION NUMBER

ACTRN12621000009819.

Germline Genetic Testing for Hereditary Breast and Ovarian Cancer: Current Concepts in Risk Evaluation

Our understanding of hereditary breast and ovarian cancer has significantly improved over the past two decades. In addition to BRCA1/2, pathogenic variants in several other DNA-repair genes have been shown to increase the risks of breast and ovarian cancer. The magnitude of cancer risk is impacted not only by the gene involved, but also by family history of cancer, polygenic risk scores, and, in certain genes, pathogenic variant type or location. While estimates of breast and ovarian cancer risk associated with pathogenic variants are available, these are predominantly based on studies of high-risk populations with young age at diagnosis of cancer, multiple primary cancers, or family history of cancer. More recently, breast cancer risk for germline pathogenic variant carriers has been estimated from population-based studies. Here, we provide a review of the field of germline genetic testing and risk evaluation for hereditary breast and ovarian cancers in high-risk and population-based settings.

Untapped Potential of Poly(ADP-Ribose) Polymerase Inhibitors: Lessons Learned From the Real-World Clinical Homologous Recombination Repair Mutation Testing

Background

Testing for homologous recombination deficiency (HRD) mutations is pivotal to assess individual risk, to proact preventive measures in healthy carriers and to tailor treatments for cancer patients. Increasing prominence of poly(ADP-ribose) polymerase (PARP) inhibitors with remarkable impact on molecular-selected patient survival across diverse nosologies, ingrains testing for BRCA genes and beyond in clinical practice. Nevertheless, testing strategies remain a question of debate. While several pathogenic BRCA1/2 gene variants have been described as founder pathogenic mutations frequently found in patients from Russia, other homologous recombination repair (HRR) genes have not been sufficiently explored. In this study, we present real-world data of routine HRR gene testing in Russia.

Methods

We evaluated clinical and sequencing data from cancer patients who had germline/somatic next-generation sequencing (NGS) HRR gene testing in Russia (BRCA1/2/ATM/CHEK2, or 15 HRR genes). The primary objectives of this study were to evaluate the frequency of BRCA1/2 and non-BRCA gene mutations in real-world unselected patients from Russia, and to determine whether testing beyond BRCA1/2 is feasible.

Results

Data of 2,032 patients were collected from February 2021 to February 2023. Most had breast (n = 715, 35.2%), ovarian (n = 259, 12.7%), pancreatic (n = 85, 4.2%), or prostate cancer (n = 58, 2.9%). We observed 586 variants of uncertain significance (VUS) and 372 deleterious variants (DVs) across 487 patients, with 17.6% HRR-mutation positivity. HRR testing identified 120 (11.8%) BRCA1/2-positive, and 172 (16.9%) HRR-positive patients. With 51 DVs identified in 242 formalin-fixed paraffin-embedded (FFPE), testing for variant origin clarification was required in one case (0.4%). Most BRCA1/2 germline variants were DV (121 DVs, 26 VUS); in non-BRCA1/2 genes, VUS were ubiquitous (53 DVs, 132 VUS). In silico prediction identified additional 4.9% HRR and 1.2% BRCA1/2/ATM/CHEK2 mutation patients.

Conclusions

Our study represents one of the first reports about the incidence of DV and VUS in HRR genes, including genes beyond BRCA1/2, identified in cancer patients from Russia, assessed by NGS. In silico predictions of the observed HRR gene variants suggest that non-BRCA gene testing is likely to result in higher frequency of patients who are candidates for PARP inhibitor therapy. Continuing sequencing efforts should clarify interpretation of frequently observed non-BRCA VUS.

BRCAness, DNA gaps, and gain and loss of PARP inhibitor-induced synthetic lethality

Mutations in the tumor-suppressor genes BRCA1 and BRCA2 resulting in BRCA1/2 deficiency are frequently identified in breast, ovarian, prostate, pancreatic, and other cancers. Poly(ADP-ribose) polymerase (PARP) inhibitors (PARPis) selectively kill BRCA1/2-deficient cancer cells by inducing synthetic lethality, providing an effective biomarker-guided strategy for targeted cancer therapy. However, a substantial fraction of cancer patients carrying BRCA1/2 mutations do not respond to PARPis, and most patients develop resistance to PARPis over time, highlighting a major obstacle to PARPi therapy in the clinic. Recent studies have revealed that changes of specific functional defects of BRCA1/2-deficient cells, particularly their defects in suppressing and protecting single-stranded DNA gaps, contribute to the gain or loss of PARPi-induced synthetic lethality. These findings not only shed light on the mechanism of action of PARPis, but also lead to revised models that explain how PARPis selectively kill BRCA-deficient cancer cells. Furthermore, new mechanistic principles of PARPi sensitivity and resistance have emerged from these studies, generating potentially useful guidelines for predicting the PARPi response and design therapies for overcoming PARPi resistance. In this Review, we will discuss these recent studies and put them in context with the classic views of PARPi-induced synthetic lethality, aiming to stimulate the development of new therapeutic strategies to overcome PARPi resistance and improve PARPi therapy.

Hereditary Breast Cancer: BRCA Mutations and Beyond

Hereditary breast cancers are manifested by pathogenic and likely pathogenic genetic mutations. Penetrance expresses the breast cancer risk associated with these genetic mutations. Although BRCA1/2 are the most widely known genetic mutations associated with breast cancer, numerous additional genes demonstrate high and moderate penetrance for breast cancer. This review describes current genetic testing, details the specific high and moderate penetrance genes for breast cancer and reviews the current approach to screening for breast cancer in patients with these genetic mutations.

Public neoantigens in breast cancer immunotherapy (Review)

Among women globally, breast cancer is the most prevalent cancer and the leading cause of cancer‑related death. Interestingly, though genetic mutations contribute to the disease, <15% of women diagnosed with breast cancer have a family history of the disease, suggesting a prevalence of sporadic genetic mutations in breast cancer development. In the rapidly rising field of cancer genomics, neoantigen‑based immunotherapy has come to the fore. The investigation of novel proteins arising from unique somatic mutations or neoantigens have opened a new pathway for both individualized and public cancer treatments. Because they are shared among individuals with similar genetic changes, public neoantigens provide an opportunity for 'off‑the‑shelf' anticancer therapies, potentially extending the benefits to a wider patient group. The present review aimed to highlight the role of shared or public neoantigens as therapeutic targets for patients with breast cancer, emphasizing common hotspot mutations of certain genes identified in breast cancer. The clinical utilization of public neoantigen‑based therapies for breast cancer treatment were also discussed.

The Impact of a Breast Cancer Risk Assessment on the Decision for Gender-Affirming Chest Masculinization Surgery in Transgender and Gender-Diverse Individuals: A Pilot Single-Arm Educational Intervention Trial

BACKGROUND

Persons assigned female or intersex at birth and identify as transgender and/or gender-diverse (TGD) may undergo gender-affirming chest masculinization surgery (GACMS); however, GACMS is not considered equivalent to risk-reducing mastectomies (RRM). This study aimed to estimate the prevalence of elevated breast cancer (BC) risk in TGD persons, compare self-perceived versus calculated risk, and determine how risk impacts the decision for GACMS versus RRM.

METHODS

A prospective single-arm pilot educational intervention trial was conducted in individuals assigned female or intersex at birth, age ≥ 18 years, considering GACMS, without a BC history or a known pathogenic variant. BC risk was calculated using the Tyrer-Cuzik (all) and Gail models (age ≥ 35 years). Elevated risk was defined as ≥ 17%.

RESULTS

Twenty-five (N = 25) participants were enrolled with a median age of 24.0 years (interquartile range, IQR 20.0-30.0 years). All were assigned female sex at birth, most (84%) were Non-Hispanic (NH)-White, 48% identified as transgender and 40% as nonbinary, and 52% had a first- and/or second-degree family member with BC. Thirteen (52%) had elevated risk (prevalence 95% confidence interval (CI) 31.3-72.2%). Median self-perceived risk was 12% versus 17.5% calculated risk (p = 0.60). Of the 13 with elevated risk, 5 (38.5%) underwent/are scheduled to undergo GACMS, 3 (23%) of whom underwent/are undergoing RRM.

CONCLUSIONS

Over half of the cohort had elevated risk, and most of those who moved forward with surgery chose to undergo RRM. A BC risk assessment should be performed for TGD persons considering GACMS. Future work is needed to examine BC incidence and collect patient-reported outcomes. Trial Registration Number ClinicalTrials.gov (No. NCT06239766).

Spectrum and characteristics of germline PALB2 pathogenic variants in 1556 early-onset breast cancer patients in China

PURPOSE

Limited data are available regarding the partner and localizer of BRCA2 (PALB2) in Chinese patients with early breast cancer. This study aimed to assess the spectrum and characteristics of germline PALB2 pathogenic variants in this population.

METHODS

Peripheral blood samples were collected from 1556 patients diagnosed with BRCA1/2-negative early-onset breast cancer. All coding regions and exon‒intron boundaries of the PALB2 genes were screened through next-generation sequencing.

RESULTS

The prevalence of PALB2 pathogenic variants was approximately 0.77% in the cohort. Eleven PALB2 pathogenic variants were identified in twelve participants, including five frameshift mutations and six nonsense mutations. All other variants were detected once, except for PALB2 c.1056_1057del (detected twice). Two PALB2 carriers (2/12, 16.7%) have documented family history of breast cancer and/or ovarian cancer. Patients with a positive family history exhibited a threefold higher possibility of being identified as PALB2 carriers than those without a family history (2% vs. 0.69%), although the difference was not statistically significant (p = 0.178). Compared to non-carriers, PALB2 carriers has a tendency to appear in younger age (≤ 30 years) (25% vs 14.4%), human epidermal growth factor receptor-2 (HER2)-negative status (83.3% vs. 70.2%), and diagnosed with invasive micropapillary carcinoma (16.7% vs 3.1%).

CONCLUSION

The prevalence of the germline PALB2 pathogenic variants was approximately 0.77% in Chinese patients with BRCA1/2-negative early-onset breast cancer. Our findings is crucial for understanding population-specific genetic risks and offering insights that can enhance genetic counseling and genetic testing strategies in this population.

Evaluating the utility of multi-gene, multi-disease population-based panel testing accounting for uncertainty in penetrance estimates

Panel germline testing allows for the efficient detection of deleterious variants for multiple conditions, but the benefits and harms of identifying these variants are not always well understood. We present a multi-gene, multi-disease aggregate utility formula that allows the user to consider adding or removing each gene in a panel based on variant frequency, estimated penetrances, and subjective disutilities for testing positive but not developing the disease and testing negative but developing the disease. We provide credible intervals for utility that reflect uncertainty in penetrance estimates. Rare, highly penetrant deleterious variants tend to contribute positive net utilities for a wide variety of user-specified disutilities, even when accounting for parameter estimation uncertainty. However, the clinical utility of deleterious variants with moderate, uncertain penetrance depends more on assumed disutilities. The decision to include a gene on a panel depends on variant frequency, penetrance, and subjective utilities and should account for uncertainties around these factors.

Breast Cancer Risk for Women With a TP53 Pathogenic Variant

The article highlights that breast cancer risk for women with TP53 mutations depends on family history.

Meta-analysis of breast cancer risk for individuals with PALB2 pathogenic variants

Multigene panel testing now allows efficient testing of many cancer susceptibility genes leading to a larger number of mutation carriers being identified. They need to be counseled about their cancer risk conferred by the specific gene mutation. An important cancer susceptibility gene is PALB2. Multiple studies reported risk estimates for breast cancer (BC) conferred by pathogenic variants in PALB2. Due to the diverse modalities of reported risk estimates (age-specific risk, odds ratio, relative risk, and standardized incidence ratio) and effect sizes, a meta-analysis combining these estimates is necessary to accurately counsel patients with this mutation. However, this is not trivial due to heterogeneity of studies in terms of study design and risk measure. We utilized a recently proposed Bayesian random-effects meta-analysis method that can synthesize estimates from such heterogeneous studies. We applied this method to combine estimates from 12 studies on BC risk for carriers of pathogenic PALB2 mutations. The estimated overall (meta-analysis-based) risk of BC is 12.80% (6.11%-22.59%) by age 50 and 48.47% (36.05%-61.74%) by age 80. Pathogenic mutations in PALB2 makes women more susceptible to BC. Our risk estimates can help clinically manage patients carrying pathogenic variants in PALB2.

Recontact to return new or updated PALB2 genetic results in the clinical laboratory setting

OBJECTIVE

The purpose of this study was to recontact individuals with clinically actionable test results identified through a retrospective research study and to provide a framework for laboratories to recontact patients.

METHODS

Genetic testing was conducted on 2977 individuals originally referred for BRCA1 and BRCA2 hereditary breast and ovarian cancer testing that had a negative genetic test result. A gene panel was used to identify pathogenic variants in known or newly discovered genes that could explain the underlying cause of disease; however, analysis was restricted to PALB2 for the purposes of this study. A patient recontact decision tree was developed to assist in the returning of updated genetic test results to clinics and patients.

RESULTS

Novel clinically actionable pathogenic variants were identified in the PALB2 gene in 18 participants (0.6%), the majority of whom were recontacted with their new or updated genetic test results. Eight individuals were unable to be recontacted; five individuals had already learnt about their new or updated findings from genetic testing outside the context of this study; three individuals prompted cascade testing in family members; two individuals were deceased.

CONCLUSION

Novel pathogenic variants in PALB2 were identified in 18 individuals through retrospective gene panel testing. Recontacting these individuals regarding these new or updated findings had a range of outcomes. The process of conveying genomic results within this framework can be effectively accomplished while upholding patient autonomy, potentially leading to advantageous outcomes for patients and their families.

Bayesian meta-analysis of penetrance for cancer risk

Multi-gene panel testing allows many cancer susceptibility genes to be tested quickly at a lower cost making such testing accessible to a broader population. Thus, more patients carrying pathogenic germline mutations in various cancer-susceptibility genes are being identified. This creates a great opportunity, as well as an urgent need, to counsel these patients about appropriate risk-reducing management strategies. Counseling hinges on accurate estimates of age-specific risks of developing various cancers associated with mutations in a specific gene, ie, penetrance estimation. We propose a meta-analysis approach based on a Bayesian hierarchical random-effects model to obtain penetrance estimates by integrating studies reporting different types of risk measures (eg, penetrance, relative risk, odds ratio) while accounting for the associated uncertainties. After estimating posterior distributions of the parameters via a Markov chain Monte Carlo algorithm, we estimate penetrance and credible intervals. We investigate the proposed method and compare with an existing approach via simulations based on studies reporting risks for two moderate-risk breast cancer susceptibility genes, ATM and PALB2. Our proposed method is far superior in terms of coverage probability of credible intervals and mean square error of estimates. Finally, we apply our method to estimate the penetrance of breast cancer among carriers of pathogenic mutations in the ATM gene.

Meta-Analysis of Breast Cancer Risk for Individuals with PALB2 Pathogenic Variants

Background

Pathogenic variants in cancer susceptibility genes can now be tested efficiently and economically with the wide availability of multi-gene panel testing. This has resulted in an unprecedented rate of identifying individuals carrying pathogenic variants. These carriers need to be counselled about their future cancer risk conferred by the specific gene mutation. An important cancer susceptibility gene is PALB2. Several studies reported risk estimates for breast cancer (BC) associated with pathogenic variants in PALB2. Because of the variety of modalities (age specific risk, odds ratio, relative risk, and standardized incidence ratio) and effect sizes of these risk estimates, a meta-analysis of all of these estimates of BC risk is necessary to provide accurate counseling of patients with pathogenic variants in PALB2. The challenge, though, in combining these estimates is the heterogeneity of studies in terms of study design and risk measure.

Methods

We utilized a recently proposed novel Bayesian random-effects meta-analysis method that can synthesize and combine information from such heterogeneous studies. We applied this method to combine estimates from twelve different studies on BC risk for carriers of pathogenic PALB2 mutations, out of which two report age-specific penetrance, one reports relative risk, and nine report odds ratios.

Results

The estimated overall (meta-analysis based) risk of BC is 12.80% by age 50 (6.11%- 22.59%) and 48.47% by age 80 (36.05%-61.74%).

Conclusion

Pathogenic mutations in PALB2 makes women more susceptible to BC. Our risk estimates can help clinically manage patients carrying pathogenic variants in PALB2.

Age-specific breast and ovarian cancer risks associated with germline BRCA1 or BRCA2 pathogenic variants - an Asian study of 572 families

Background

Clinical management of Asian BRCA1 and BRCA2 pathogenic variants (PV) carriers remains challenging due to imprecise age-specific breast (BC) and ovarian cancer (OC) risks estimates. We aimed to refine these estimates using six multi-ethnic studies in Asia.

Methods

Data were collected on 271 BRCA1 and 301 BRCA2 families from Malaysia and Singapore, ascertained through population/hospital-based case-series (88%) and genetic clinics (12%). Age-specific cancer risks were estimated using a modified segregation analysis method, adjusted for ascertainment.

Findings

BC and OC relative risks (RRs) varied across age groups for both BRCA1 and BRCA2. The age-specific RR estimates were similar across ethnicities and country of residence. For BRCA1 carriers of Malay, Indian and Chinese ancestry born between 1950 and 1959 in Malaysia, the cumulative risk (95% CI) of BC by age 80 was 40% (36%-44%), 49% (44%-53%) and 55% (51%-60%), respectively. The corresponding estimates for BRCA2 were 29% (26-32%), 36% (33%-40%) and 42% (38%-45%). The corresponding cumulative BC risks for Singapore residents from the same birth cohort, where the underlying population cancer incidences are higher compared to Malaysia, were higher, varying by ancestry group between 57 and 61% for BRCA1, and between 43 and 47% for BRCA2 carriers. The cumulative risk of OC by age 80 was 31% (27-36%) for BRCA1 and 12% (10%-15%) for BRCA2 carriers in Malaysia born between 1950 and 1959; and 42% (34-50%) for BRCA1 and 20% (14-27%) for BRCA2 carriers of the same birth cohort in Singapore. There was evidence of increased BC and OC risks for women from >1960 birth cohorts (p-value = 3.6 × 10-5 for BRCA1 and 0.018 for BRCA2).

Interpretation

The absolute age-specific cancer risks of Asian carriers vary depending on the underlying population-specific cancer incidences, and hence should be customised to allow for more accurate cancer risk management.

Funding

Wellcome Trust [grant no: v203477/Z/16/Z]; CRUK (PPRPGM-Nov20∖100002).

Challenges to genetic testing for germline mutations associated with breast cancer among African Americans

Inequities in preventive cancer screening, diagnosis, treatment, and inferior cancer outcomes continue to pose challenges across the cancer continuum. While the exact reasons for these inferior outcomes are unknown, multiple barriers to various domains of social determinants of health (SDOH) play a vital role, leading to inequities in cancer care. These include barriers to transportation, housing, and food insecurities, contributing to delays in preventive screening and treatment. Furthermore, aggressive biologies also exist across various racial profiles with accompanying germline mutations. For example, African Americans (AAs) have a higher incidence of triple-negative breast cancer subtype and a high prevalence of BRCA1/2 gene mutations, increasing the risk of multiple cancers, warranting high-risk screening for these populations. Unfortunately, other barriers, such as financial insecurities, low health literacy rates, and lack of awareness, lead to delays in cancer screening and genetic testing, even with available high-risk screening and risk reduction procedures. In addition, physicians receive minimal interdisciplinary training to address genetic assessment, interpretation of the results, and almost no additional training in addressing the unique needs of racial minorities, leading to suboptimal delivery of genetic assessment provision resources among AAs. In this review, we discuss the confluence of factors and barriers limiting genetic testing among AAs and highlight the prevalence of germline mutations associated with increased risk of breast cancer among AAs, reflecting the need for multi-panel germline testing as well as education regarding hereditary cancer risks in underserved minorities.

Characterizing PALB2 intragenic duplication breakpoints in a triple-negative breast cancer case using long-read sequencing

Introduction

Accurate identification and characterization of Large Genomic Rearrangements (LGR), especially duplications, are crucial for precise diagnosis and risk assessment. In this report, we characterized an intragenic duplication breakpoint of PALB2 to determine its pathogenicity significance.

Methods

A 52-year-old female with triple-negative breast cancer was diagnosed with a novel PALB2 LGR. An efficient and accurate methodology was applied, combining long-read sequencing and transcript analysis for the rapid characterization of the duplication.

Results

Duplication of exons 5 and 6 of PALB2 was validated by transcript analysis. Long-read sequencing enabled the localization of breakpoints within Alu elements, providing insights into the mechanism of duplication via non-allelic homologous recombination.

Conclusion

Using our combined methodology, we reclassified the PALB2 duplication as a pathogenic variant. This reclassification suggests a possible causative link between this specific genetic alteration and the aggressive phenotype of the patient.

Germline RECQL gene mutations in Chinese patients with breast cancer

Introduction

Breast cancer is the most common malignant tumor in women, seriously threatening health and survival. TP-dependent DNA helicase Q1 (RECQL) is a breast cancer susceptibility gene with possible familial links. However, RECQL gene mutations among Chinese women with breast cancer have not been evaluated. Therefore, this study assessed RECQL mutations and their relationships with clinicopathological and epidemiological characteristics in Chinese women with breast cancer.

Method

Clinical information was also obtained via the hospital information system and a follow-up questionnaire. Peripheral venous blood (2 mL) was extracted from all patients and stored at -80°C for future use; the early venous blood samples were from our hospital's sample bank. RECQL gene sequencing were performed by the Shanghai Aishe Gene Company (China).

Results

We found that a RECQL mutation is a susceptibility factor for breast cancer. Moreover, patients with RECQL mutations were more likely to have a family history of breast cancer than those without. Also, patients with RECQL variants of uncertain significance (VUS) were less likely to develop invasive ductal carcinoma than those without. In addition, unexplained RECQL mutations occurred more often in patients with human epidermal growth factor receptor 2+ breast cancer than in those with other subtypes.

Discussion

These results provide a basis for creating screening criteria specific to Chinese women. However, the frequency of RECQL mutations was low, and the number of pathogenic mutations was too small and could not be analyzed. Thus, more extensive, long-term studies that include other functional experiments are needed to verify these results.

Cost-Effectiveness of Population-Based Multigene Testing for Breast and Ovarian Cancer Prevention

Importance

The current method of BRCA testing for breast and ovarian cancer prevention, which is based on family history, often fails to identify many carriers of pathogenic variants. Population-based genetic testing offers a transformative approach in cancer prevention by allowing for proactive identification of any high-risk individuals and enabling early interventions.

Objective

To assess the lifetime incremental effectiveness, costs, and cost-effectiveness of population-based multigene testing vs family history-based testing.

Design, Setting, and Participants

This economic evaluation used a microsimulation model to assess the cost-effectiveness of multigene testing (BRCA1, BRCA2, and PALB2) for all women aged 30 to 35 years compared with the current standard of care that is family history based. Carriers of pathogenic variants were offered interventions, such as magnetic resonance imaging with or without mammography, chemoprevention, or risk-reducing mastectomy and salpingo-oophorectomy, to reduce cancer risk. A total of 2000 simulations were run on 1 000 000 women, using a lifetime time horizon and payer perspective, and costs were adjusted to 2022 US dollars. This study was conducted from September 1, 2020, to December 15, 2023.

Main Outcomes and Measures

The main outcome measure was the incremental cost-effectiveness ratio (ICER), quantified as cost per quality-adjusted life-year (QALY) gained. Secondary outcomes included incremental cost, additional breast and ovarian cancer cases prevented, and excess deaths due to coronary heart disease (CHD).

Results

The study assessed 1 000 000 simulated women aged 30 to 35 years in the US. In the base case, population-based multigene testing was more cost-effective compared with family history-based testing, with an ICER of $55 548 per QALY (95% CI, $47 288-$65 850 per QALY). Population-based multigene testing would be able to prevent an additional 1338 cases of breast cancer and 663 cases of ovarian cancer, but it would also result in 69 cases of excess CHD and 10 excess CHD deaths per million women. The probabilistic sensitivity analyses show that the probability that population-based multigene testing is cost-effective was 100%. When the cost of the multigene test exceeded $825, population-based testing was no longer cost-effective (ICER, $100 005 per QALY; 95% CI, $87 601-$11 6323).

Conclusions and Relevance

In this economic analysis of population-based multigene testing, population-based testing was a more cost-effective strategy for the prevention of breast cancer and ovarian cancer when compared with the current family history-based testing strategy at the $100 000 per QALY willingness-to-pay threshold. These findings support the need for more comprehensive genetic testing strategies to identify pathogenic variant carriers and enable informed decision-making for personalized risk management.

Pleomorphic/solid lobular carcinoma of male breast with PALB2 germline mutation: case report and literature review

Male breast cancer (MBC) accounts for approximately 1% of all breast cancers and among these infiltrating lobular carcinomas (ILC) represents only 1-2% of all MBC cases. Pleomorphic invasive lobular carcinoma (PILC) is an aggressive variant of ILC with only eight cases reported until now in males. Up to 10% of MBC cases have a germline pathogenic variant in a predisposing gene such as BRCA1 and BRCA2 genes. Mutations in PALB2 (partner and localizer of BRCA2) have been reported in men with breast cancer, with a frequency that ranges from 0.8 to 6.4%, but it has never been reported in male ILC. Here, we report a rare and interesting case of an invasive pleomorphic/solid lobular carcinoma, which carries a pathogenic variant in PALB2 gene, and a family history of breast cancer without other well defined risk factors for developing this type of neoplasia. In addition, we review the current literature.

Ethnicity-specific BRCA1, BRCA2, PALB2, and ATM pathogenic alleles in breast and ovarian cancer patients from the North Caucasus

BACKGROUND

Mountain areas of the North Caucasus host several large ethnic communities that have preserved their national identity over the centuries.

METHODS

This study involved high-grade serous ovarian cancer (HGSOC) and breast cancer (BC) patients from Dagestan (HGSOC: 37; BC: 198), Kabardino-Balkaria (HGSOC: 68; BC: 155), North Ossetia (HGSOC: 51; BC: 104), Chechnya (HGSOC: 68; BC: 79), Ingushetia (HGSOC: 19; BC: 103), Karachay-Cherkessia (HGSOC: 13; BC: 47), and several Armenian settlements (HGSOC: 16; BC: 101). The group of BC patients was enriched by young-onset and/or family history-positive and/or bilateral and/or receptor triple-negative cases. The entire coding region of BRCA1, BRCA2, PALB2, and ATM genes was analyzed by next-generation sequencing.

RESULTS

A significant contribution of BRCA1/2 pathogenic variants (PVs) to HGSOC and BC development was observed across all North Caucasus regions (HGSOC: 19-39%; BC: 6-13%). Founder alleles were identified in all ethnic groups studied, e.g., BRCA1 c.3629_3630delAG in Chechens, BRCA2 c.6341delC in North Ossetians, BRCA2 c.5351dupA in Ingush, and BRCA1 c.2907_2910delTAAA in Karachays. Some BRCA1/2 alleles, particularly BRCA2 c.9895C > T, were shared by several nationalities. ATM PVs were detected in 14 patients, with c.1673delG and c.8876_8879delACTG alleles occurring twice each. PALB2 heterozygosity was observed in 5 subjects, with one variant seen in 2 unrelated women.

CONCLUSION

This study adds to the evidence for the global-wide contribution of BRCA1/2 genes to HGSOC and BC morbidity, although the spectrum of their PVs is a subject of ethnicity-specific variations. The data on founder BRCA1/2 alleles may be considered when adjusting the BRCA1/2 testing procedure to the ethnic origin of patients.

Does genetic testing offer utility as a supplement to traditional family health history intake for inherited disease risk?

CONTENT

This study examines the potential utility of genetic testing as a supplement to family health history to screen for increased risk of inherited disease. Medical conditions are often misreported or misunderstood, especially those related to different forms of cardiac disease (arrhythmias vs. structural heart disease vs. coronary artery disease), female organ cancers (uterine vs. ovarian vs. cervical), and type of cancer (differentiating primary cancer from metastases to other organs). While these nuances appear subtle, they can dramatically alter medical management. For example, different types of cardiac failure (structural, arrhythmia, and coronary artery disease) have inherited forms that are managed with vastly different approaches.

METHODS

Using a dataset of over 6,200 individuals who underwent genetic screening, we compared the ability of genetic testing and traditional family health history to identify increased risk of inherited disease. A further, in-depth qualitative study of individuals for whom risk identified through each method was discordant, explored whether this discordance could be addressed through changes in family health history intake.

FINDINGS

Of 90 individuals for whom genetic testing indicated significant increased risk for inherited disease, two-thirds (66%) had no corroborating family health history. Specifically, we identify cardiomyopathy, arrhythmia, and malignant hyperthermia as conditions for which discordance between genetic testing and traditional family health history was greatest, and familial hypercholesterolaemia, Lynch syndrome, and hereditary breast and ovarian cancer as conditions for which greater concordance existed.

CONCLUSION

We conclude that genetic testing offers utility as a supplement to traditional family health history intake over certain conditions.

Prevalence of BRCA1, BRCA2, and PALB2 genomic alterations among 924 Taiwanese breast cancer assays with tumor-only targeted sequencing: extended data analysis from the VGH-TAYLOR study

BACKGROUND

The homologous recombination (HR) repair pathway for DNA damage, particularly the BRCA1 and BRCA2 genes, has become a target for cancer therapy, with poly ADP-ribose polymerase (PARP) inhibitors showing significant outcomes in treating germline BRCA1/2 (gBRCA1/2) mutated breast cancer. Recent studies suggest that some patients with somatic BRCA1/2 (sBRCA1/2) mutation or mutations in HR-related genes other than BRCA1/2 may benefit from PARP inhibitors as well, particularly those with PALB2 mutations. The current analysis aims to evaluate the prevalence of genetic alterations specific to BRCA1, BRCA2, and PALB2 in a large cohort of Taiwanese breast cancer patients through tumor-targeted sequencing.

METHODS

A total of 924 consecutive assays from 879 Taiwanese breast cancer patients underwent tumor-targeted sequencing (Thermo Fisher Oncomine Comprehensive Assay v3). We evaluated BRCA1, BRCA2, and PALB2 mutational profiles, with variants annotated and curated by the ClinVAR, the Oncomine™ Knowledgebase Reporter, and the OncoKB™. We also conducted reflex germline testing using either whole exome sequencing (WES) or whole genome sequencing (WGS), which is ongoing.

RESULTS

Among the 879 patients analyzed (924 assays), 130 had positive mutations in BRCA1 (3.1%), BRCA2 (8.6%), and PALB2 (5.2%), with a total of 14.8% having genetic alterations. Co-occurrence was noted between BRCA1/BRCA2, BRCA1/PALB2, and BRCA2/PALB2 mutations. In BRCA1-mutated samples, only p.K654fs was observed in three patients, while other variants were observed no more than twice. For BRCA2, p.N372H was the most common (26 patients), followed by p.S2186fs, p.V2466A, and p.X159_splice (5 times each). For PALB2, p.I887fs was the most common mutation (30 patients). This study identified 176 amino acid changes; 60.2% (106) were not documented in either ClinVAR or the Oncomine™ Knowledgebase Reporter. Using the OncoKB™ for annotation, 171 (97.2%) were found to have clinical implications. For the result of reflex germline testing, three variants (BRCA1 c.1969_1970del, BRCA1 c.3629_3630del, BRCA2 c.8755-1G > C) were annotated as Pathogenic/Likely pathogenic (P/LP) variants by ClinVar and as likely loss-of-function or likely oncogenic by OncoKB; while one variant (PALB2 c.448C > T) was not found in ClinVar but was annotated as likely loss-of-function or likely oncogenic by OncoKB.

CONCLUSION

Our study depicted the mutational patterns of BRCA1, BRCA2, and PALB2 in Taiwanese breast cancer patients through tumor-only sequencing. This highlights the growing importance of BRCA1/2 and PALB2 alterations in breast cancer susceptibility risk and the treatment of index patients. We also emphasized the need to meticulously annotate variants in cancer-driver genes as well as actionable mutations across multiple databases.

Genetic contribution of breast cancer genes in women of black African origin

Breast cancer (BC) is an increasing public health issue worldwide. BC incidence and mortality rates are rising in transitioning countries in Africa, with the most rapid increase occurring in Sub-Saharan Africa (SSA). Female BC represents 25.8% of all cancer diagnosis in SSA. Early age at onset, high grade and triple negative tumors are hallmarks of BC in this region, associated with germline pathogenic variants in susceptibility genes. While several genes have been associated with genetic predisposition (BRCA1, BRCA2, PALB2, TP53, PTEN, CDH1, STK11, ATM, CHEK2, NBN, BARD1, BRIP1, RAD50, RAD51C, RAD51D, … ), most studies have reported contribution of BRCA1 and BRCA2 pathogenic variants. Genetic contribution of BRCA genes has been estimated at 27% in Caucasian women. Available data from population of African origin are scarce and have mainly focused on pathogenic variants of BRCA1 and BRCA2. Reports from main studies on large sample size highlighted that BRCA1 still the major gene associated with BC in SSA. In addition, BRCA2, PALB2, and P53, are also on the top major genes with high penetrance, associated with BC. Mutation spectrum of BC genes in black African women seems to be different from Caucasian with increasing number of founder mutations identified. We hypothesis that the genetic contribution of known BC genes may be different between women of black African origin compared to Caucasians. In this review we explore the genetic contribution of known breast cancer genes in women of African origin, and discuss perspectives for prevention and patients care strategies in the era of precision medicine.

Molecularly Targeted Therapies for Triple Negative Breast Cancer: History, Advances, and Future Directions

Triple negative breast cancer (TNBC) remains the subtype with poorest prognosis. Despite the subtype's heterogeneity, there is still a paucity in effective targeted therapeutics that offer both good efficacy and tolerability, and chemotherapy remains the backbone of modern TNBC therapy. In the past few years, immunotherapy as well as novel therapeutic modalities like antibody-drug conjugates (ADCs) have shown clinical benefit and have been FDA approved in various clinical stages of unselected TNBC. However, there has not been similar advancement in molecularly targeted therapies, especially when compared to advancements seen in hormone receptor (HR)-positive or HER2-positive breast cancer. PARP inhibitors have been approved for BRCA-mutated TNBC, but responses are short-lived, and resistance remains a barrier for current treatment. PI3K pathway inhibitors approved in HR+ breast cancer has not worked for TNBC and continue to have significant dose-limiting adverse effects. EGFR inhibition has been thoroughly explored in TNBC, but all trials so far have shown minimal efficacy. Nevertheless, despite these setbacks, current research in targeted therapy for TNBC holds great promise in overcoming the barriers of the past and developing novel therapeutic approaches for the future. In this review, we describe molecular targets both identified and validated in the treatment of TNBC, discuss the historical efforts towards development of targeted agents and current areas of improvement, and address promising advances that have the potential to improve outcomes in this heterogenous and aggressive breast cancer subtype. Immunotherapy, ADCs, and AR targeting will be discussed in separate reviews of this edition.

Exome Sequencing Reveals Novel Germline Variants in Breast Cancer Patients in the Southernmost Region of Thailand

Germline carriers of pathogenic variants in cancer susceptibility genes are at an increased risk of breast cancer (BC). We characterized germline variants in a cohort of 151 patients diagnosed with epithelial BC in the southernmost region of Thailand, where the predominant ethnicity differs from that of the rest of the country. Whole exome sequencing was used to identify and subsequently filter variants present in 26 genes known to be associated with cancer predisposition. Of the 151 individuals assessed, 23, corresponding to 15.2% of the sample, exhibited the presence of one or more pathogenic or likely pathogenic variants associated with BC susceptibility. We identified novel germline truncating variants in BRIP1, CHEK2, MSH6, PALB2, and PTEN and annotated variants of uncertain significance (VUSs), both novel and previously documented. Therefore, it is advisable to use genetic testing as an additional risk screening method for BC in this area.

Combined Bioinformatic and Splicing Analysis of Likely Benign Intronic and Synonymous Variants Reveals Evidence for Pathogenicity

Background

Current clinical variant analysis pipelines focus on coding variants and intronic variants within 10-20 bases of an exon-intron boundary that may affect splicing. The impact of newer splicing prediction algorithms combined with in vitro splicing assays on rare variants currently considered Benign/Likely Benign (B/LB) is unknown.

Methods

Exome sequencing data from 576 pediatric cancer patients enrolled in the Texas KidsCanSeq study were filtered for intronic or synonymous variants absent from population databases, predicted to alter splicing via SpliceAI (>0.20), and scored as potentially deleterious by CADD (>10.0). Total cellular RNA was extracted from monocytes and RT-PCR products analyzed. Subsequently, rare synonymous or intronic B/LB variants in a subset of genes submitted to ClinVar were similarly evaluated. Variants predicted to lead to a frameshifted splicing product were functionally assessed using an in vitro splicing reporter assay in HEK-293T cells.

Results

KidsCanSeq exome data analysis revealed a rare, heterozygous, intronic variant (NM_177438.3(DICER1):c.574-26A>G) predicted by SpliceAI to result in gain of a secondary splice acceptor site. The proband had a personal and family history of pleuropulmonary blastoma consistent with DICER1 syndrome but negative clinical sequencing reports. Proband RNA analysis revealed alternative DICER1 transcripts including the SpliceAI-predicted transcript.Similar bioinformatic analysis of synonymous or intronic B/LB variants (n=31,715) in ClinVar from 61 Mendelian disease genes yielded 18 variants, none of which could be scored by MaxEntScan. Eight of these variants were assessed (DICER1 n=4, CDH1 n=2, PALB2 n=2) using in vitro splice reporter assay and demonstrated abnormal splice products (mean 66%; range 6% to 100%). Available phenotypic information from submitting laboratories demonstrated DICER1 phenotypes in 2 families (1 variant) and breast cancer phenotypes for PALB2 in 3 families (2 variants).

Conclusions

Our results demonstrate the power of newer predictive splicing algorithms to highlight rare variants previously considered B/LB in patients with features of hereditary conditions. Incorporation of SpliceAI annotation of existing variant data combined with either direct RNA analysis or in vitro assays has the potential to identify disease-associated variants in patients without a molecular diagnosis.

A Case Report of Breast Implant-Associated Anaplastic Large-Cell Lymphoma in a PALB2 Mutation-Positive Woman

Breast implant-associated anaplastic large-cell lymphoma (BIA-ALCL) is a rare peripheral T-cell lymphoma composed of anaplastic pleomorphic T cells. The first case was reported in 1997 but was not recognized until 2016 by the World Health Organization. The exact incidence is unknown but is estimated to be 0.1 to 0.3 per 100,000 women with implants. Almost every case has been found in women with textured breast implants. The median time of onset after implantation is 10.7 years. Patients presenting with localized disease, most commonly manifesting as breast enlargement, can be managed solely with surgical resection and have a 100% survival rate. This report describes a PALB2 mutation-positive woman with a strong family history of breast cancer who underwent prophylactic bilateral nipple-sparing mastectomy with textured silicone implant placement. She was diagnosed with BIA-ALCL less than 4 years later after seroma aspiration. She was treated with implant removal and capsulectomy; but, surprisingly, final surgical pathology did not show any malignancy.

Factors that differentiate cancer risk management decisions among females with pathogenic/likely pathogenic variants in PALB2, CHEK2, and ATM

PURPOSE

Following disclosure of pathogenic or likely pathogenic variants in hereditary cancer genes, patients face cancer risk management decisions. Through this mixed-methods study, we investigated cancer risk management decisions among females with pathogenic or likely pathogenic variants in PALB2, CHEK2, and ATM to understand why some patients follow National Comprehensive Cancer Network guidelines, whereas others do not.

METHODS

Survey and interview data were cross-analyzed using a 3-stage approach. Identified factors were used to conduct coincidence analysis and differentiate between combinations of factors that result in following or not following guidelines.

RESULTS

Of the 13 participants who underwent guideline inconsistent prophylactic surgery, 12 fit 1 of 3 unique patterns: (1) cancer-related anxiety in the absence of trust in care, (2) provider recommending surgery inconsistent with National Comprehensive Cancer Network guidelines, or (3) surgery occurring before genetic testing. Two unique patterns were found among 18 of 20 participants who followed guidelines: (1) anxiety along with trust in care or (2) lack of anxiety and no prophylactic surgery before testing.

CONCLUSION

Health care provider recommendations and trust in care may influence whether individuals receive care that is congruent with risk levels conferred by specific genes. Interventions are needed to improve provider knowledge, patient trust in non-surgical care, and patient anxiety.

BRCA1 the Versatile Defender: Molecular to Environmental Perspectives

The evolving history of BRCA1 research demonstrates the profound interconnectedness of a single protein within the web of crucial functions in human cells. Mutations in BRCA1, a tumor suppressor gene, have been linked to heightened breast and ovarian cancer risks. However, despite decades of extensive research, the mechanisms underlying BRCA1's contribution to tissue-specific tumor development remain elusive. Nevertheless, much of the BRCA1 protein's structure, function, and interactions has been elucidated. Individual regions of BRCA1 interact with numerous proteins to play roles in ubiquitination, transcription, cell checkpoints, and DNA damage repair. At a cellular scale, these BRCA1 functions coordinate tumor suppression, R-loop prevention, and cellular differentiation, all of which may contribute to BRCA1's role in cancer tissue specificity. As research on BRCA1 and breast cancer continues to evolve, it will become increasingly evident that modern materials such as Bisphenol A should be examined for their relationship with DNA stability, cancer incidence, and chemotherapy. Overall, this review offers a comprehensive understanding of BRCA1's many roles at a molecular, cellular, organismal, and environmental scale. We hope that the knowledge gathered here highlights both the necessity of BRCA1 research and the potential for novel strategies to prevent and treat cancer in individuals carrying BRCA1 mutations.

Surgical options for patients with early-stage breast cancer and pathogenic germline variants: an oncologist perspectives

Breast cancer continues to be the most common cancer diagnosed among women worldwide. Family history of breast cancer is frequently encountered, and 5-15% of patients may carry inherited pathogenic germline variants, identification of which can be helpful for both; patients themselves and their unaffected close relatives. The availability and affordability of molecular diagnostics, like next generation sequencing (NGS), had resulted in wider adoption of such technologies to detect pathogenic variants of cancer-predisposing genes. International guidelines had recently broadened the indications for germline genetic testing to include much more patients, and also expanded the testing to include multi-gene panels, while some professional societies are calling for universal testing of all newly diagnosed patients with breast cancer, regardless of their age, personal or family history. The risk of experiencing a contralateral breast cancer (CBC) or ipsilateral recurrence, is well known. Such risk is highest with variants like BRCA1 and BRCA2, but less well-studied with other less common variants. The optimal local therapy for women with BRCA-associated breast cancer remains controversial, but tends to be aggressive and may involve bilateral mastectomies, which may not have any survival advantage. Additionally, surgical management of unaffected women, known to carry a pathogenic cancer-predisposing gene, may vary from surveillance to bilateral mastectomies, too. The oncological safety, and the higher satisfaction of unaffected women and patients with new surgical techniques, like the skin-sparing (SSM) and nipple-sparing (NSM) mastectomies, eased up the process of counselling. In this review, we address the oncological safety of less aggressive surgical options for both; patients and unaffected carriers.

Risk of estrogen receptor-specific breast cancer by family history of estrogen receptor subtypes and other cancers

BACKGROUND

The extent to which the risk of estrogen receptor (ER)-specific breast cancer is associated with ER status of breast cancer and other cancers among first-degree relatives is unclear.

METHODS

This population-based cohort included 464 707 cancer-free women in Stockholm, Sweden, during 1978-2019. For ER-negative and ER-positive breast cancers, we estimated hazard ratios (HRs) associated with ER status of female first-degree relatives with breast cancer and of other cancers in all first-degree relatives. Associations between ER-negative and ER-positive status by family cancer history were estimated using logistic regression in a case-only design.

RESULTS

Women with familial ER-positive breast cancer had 1.87 times (95% confidence interval [CI] = 1.77 to 1.97) higher risk of ER-positive subtype, whereas the corresponding hazard ratio for ER-negative was 2.54 (95% CI = 2.08 to 3.10) when having familial ER-negative breast cancer. The risk increased with an increasing number of female first-degree relatives having concordant subtypes and younger age at diagnosis (Ptrend <.001 for both). Nonbreast cancers among first-degree relatives were associated with both ER-positive (HR = 1.14, 95% CI = 1.10 to 1.17) and ER-negative (HR = 1.08, 95% CI = 1.01 to 1.16) breast cancers. Compared with women with ER-positive breast cancer, women with ER-negative breast cancer were more likely to have family history of liver (odds ratio [OR] = 1.33, 95% CI = 1.05 to 1.67), ovary (OR = 1.28, 95% CI = 1.01 to 1.61), and testicle cancer (OR = 1.79, 95% CI = 1.01 to 3.16) but less likely to have family history of endometrial cancer (OR = 0.77, 95% CI = 0.60 to 1.00) and leukemia (OR = 0.72, 95% CI = 0.56 to 0.91).

CONCLUSIONS

Risk of ER-specific breast cancer differs according to ER status of female first-degree relatives with breast cancer and some other cancers of first-degree relatives. This family history information should be considered in the individual risk prediction for ER subtypes.

Mutational spectrum of DNA damage and mismatch repair genes in prostate cancer

Over the past few years, a number of studies have revealed that a significant number of men with prostate cancer had genetic defects in the DNA damage repair gene response and mismatch repair genes. Certain of these modifications, notably gene alterations known as homologous recombination (HRR) genes; PALB2, CHEK2 BRCA1, BRCA2, ATM, and genes for DNA mismatch repair (MMR); MLH1, MSH2, MSH6, and PMS2 are connected to a higher risk of prostate cancer and more severe types of the disease. The DNA damage repair (DDR) is essential for constructing and diversifying the antigen receptor genes required for T and B cell development. But this DDR imbalance results in stress on DNA replication and transcription, accumulation of mutations, and even cell death, which compromises tissue homeostasis. Due to these impacts of DDR anomalies, tumor immunity may be impacted, which may encourage the growth of tumors, the release of inflammatory cytokines, and aberrant immune reactions. In a similar vein, people who have altered MMR gene may benefit greatly from immunotherapy. Therefore, for these treatments, mutational genetic testing is indicated. Mismatch repair gene (MMR) defects are also more prevalent than previously thought, especially in patients with metastatic disease, high Gleason scores, and diverse histologies. This review summarizes the current information on the mutation spectrum and clinical significance of DDR mechanisms, such as HRR and MMR abnormalities in prostate cancer, and explains how patient management is evolving as a result of this understanding.

Polygenic scores in cancer

Since the publication of the first genome-wide association study for cancer in 2007, thousands of common alleles that are associated with the risk of cancer have been identified. The relative risk associated with individual variants is small and of limited clinical significance. However, the combined effect of multiple risk variants as captured by polygenic scores (PGSs) may be much greater and therefore provide risk discrimination that is clinically useful. We review the considerable research efforts over the past 15 years for developing statistical methods for PGSs and their application in large-scale genome-wide association studies to develop PGSs for various cancers. We review the predictive performance of these PGSs and the multiple challenges currently limiting the clinical application of PGSs. Despite this, PGSs are beginning to be incorporated into clinical multifactorial risk prediction models to stratify risk in both clinical trials and clinical implementation studies.

Racial disparities in cancer care, an eyeopener for developing better global cancer management strategies

BACKGROUND

In the last few decades, advancements in cancer research, both in the field of cancer diagnostics as well as treatment of the disease have been extensive and multidimensional. Increased availability of health care resources and growing awareness has resulted in the reduction of consumption of carcinogens such as tobacco; adopting various prophylactic measures; cancer testing on regular basis and improved targeted therapies have greatly reduced cancer mortality among populations, globally. However, this notable reduction in cancer mortality is discriminate and reflective of disparities between various ethnic populations and economic classes. Several factors contribute to this systemic inequity, at the level of diagnosis, cancer prognosis, therapeutics, and even point-of-care facilities.

RECENT FINDINGS

In this review, we have highlighted cancer health disparities among different populations around the globe. It encompasses social determinants such as status in society, poverty, education, diagnostic approaches including biomarkers and molecular testing, treatment as well as palliative care. Cancer treatment is an active area of constant progress and newer targeted treatments like immunotherapy, personalized treatment, and combinatorial therapies are emerging but these also show biases in their implementation in various sections of society. The involvement of populations in clinical trials and trial management is also a hotbed for racial discrimination. The immense progress in cancer management and its worldwide application needs a careful evaluation by identifying the biases in racial discrimination in healthcare facilities.

CONCLUSION

Our review gives a comprehensive evaluation of this global racial discrimination in cancer care and would be helpful in designing better strategies for cancer management and decreasing mortality.

Poly(ADP-ribose) polymerase inhibitors in the treatment landscape of triple-negative breast cancer (TNBC)

OBJECTIVE

Chemotherapy is the mainstay for triple-negative breast cancer (TNBC) patients. Over the years, the use of chemotherapy for these patients has demonstrated many adversities, including toxicity and resistance, which suggested the need to develop novel alternative therapeutic options, such as poly(ADP-ribose) polymerase inhibitors (PARPi). Herein, we provide an overview on PARPi, mechanisms of action and the role of biomarkers in PARPi sensitivity trials, clinical advances in PARPi therapy for TNBC patients based on the most recent studies and findings of clinical trials, and challenges that prevent PARP inhibitors from achieving high efficacy such as resistance and overlapping toxicities with other chemotherapies.

DATA SOURCES

Searching for relevant articles was done using PubMed and Cochrane Library databases by using the keywords including TNBC; chemotherapy; PARPi; BRCA; homologous recombination repair (HRR). Studies had to be published in full-text in English in order to be considered.

DATA SUMMARY

Although PARPi have been used in the treatment of local/metastatic breast malignancies that are HER2 negative and has a germline BRCA mutation, several questions are still to be answered in order to maximize the clinical benefit of PARP inhibitors in TNBC treatment, such as questions related to the optimal use in the neoadjuvant and metastatic settings as well as the best combinations with various chemotherapies.

CONCLUSIONS

PARPi are emerging treatment options for patients with gBRCA1/2 mutations. Determining patients that are most likely to benefit from PARPi and identifying the optimal treatment combinations with high efficacy and fewer side effects are currently ongoing.

PALB2 Variants Extend the Mutational Profile of Hungarian Patients with Breast and Ovarian Cancer

BACKGROUND

The pathogenic/likely pathogenic (P/LP) variant detection rate and profile of PALB2, the third most important breast cancer gene, may vary between different populations.

METHODS

PALB2 was analyzed in peripheral blood samples of three independent cohorts: prospectively between September 2021 and March 2023 (i) in 1280 consecutive patients with breast and/or ovarian cancer (HBOC), (ii) in 568 patients with other cancers (controls), and retrospectively, (iii) in 191 young breast cancer (<33 years, yBC) patients. These data were compared with data of 134,187 non-cancer individuals retrieved from the Genome Aggregation Database.

RESULTS

Altogether, 235 cases (235/1280; 18.3%) carried at least one P/LP variant in one of the HBOC susceptibility genes. P/LP PALB2 variants were identified in 18 patients (1.4%; 18/1280) in the HBOC and 3 cases (1.5%; 3/191) in the yBC group. In the control group, only one patient had a disease-causing PALB2 variant (0.17%; 1/568) as a secondary finding not related to the disease, which was similar (0.15%; 205/134,187) in the non-cancer control group. The NM_024675.4:c.509_510delGA variant was the most common among our patients (33%; 6/18). We did not find a significant difference in the incidence of PALB2 disease-causing variants according to age; however, the median age of tumor onset was lower in PALB2 P/LP carriers versus wild-type patients (44 vs. 48 years). In our cohort, the odds ratio for breast cancer risk in women with PALB2 P/LP variants was between 8.1 and 9.3 compared to non-HBOC cancer patients and the non-cancer population, respectively.

CONCLUSIONS

PALB2 P/LP variants are not uncommon among breast and/or ovarian cancer patients. Their incidence was the same in the two breast cancer cohorts studied but may occur rarely in patients with non-breast/ovarian cancer. The c.509_510delGA variant is particularly common in the studied Hungarian patient population.

Clinical Impact of Polygenic Risk Score for Breast Cancer Risk Prediction in 382 Individuals with Hereditary Breast and Ovarian Cancer Syndrome

Single nucleotide polymorphisms are currently not considered in breast cancer (BC) risk predictions used in daily practice of genetic counselling and clinical management of familial BC in Germany. This study aimed to assess the clinical value of incorporating a 313-variant-based polygenic risk score (PRS) into BC risk calculations in a cohort of German women with suspected hereditary breast and ovarian cancer syndrome (HBOC). Data from 382 individuals seeking counselling for HBOC were analysed. Risk calculations were performed using the Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm with and without the inclusion of the PRS. Changes in risk predictions and their impact on clinical management were evaluated. The PRS led to changes in risk stratification based on 10-year risk calculations in 13.6% of individuals. Furthermore, the inclusion of the PRS in BC risk predictions resulted in clinically significant changes in 12.0% of cases, impacting the prevention recommendations established by the German Consortium for Hereditary Breast and Ovarian Cancer. These findings support the implementation of the PRS in genetic counselling for personalized BC risk assessment.

Management of PALB2-associated breast cancer: A literature review and case report

Germline pathogenic variants (PV) of the PALB2 tumor suppressor gene are associated with an increased risk of breast, pancreatic, and ovarian cancer. In previous research, PALB2-associated breast cancer showed aggressive clinicopathological phenotypes, particularly triple-negative subtype, and higher mortality regardless of tumor stage, type of chemotherapy nor hormone receptor status. The identification of this germline alteration may have an impact on clinical management of breast cancer (BC) from the surgical approach to the systemic treatment choice. We herein report the case of a patient with a germline PV of PALB2, diagnosed with locally advanced PD-L1 positive triple-negative BC, who progressed after an immune checkpoint inhibitor (ICI)-containing regimen and then experienced a pathologic complete response after platinum-based chemotherapy. This case report hints a major role of the germline PALB2 alteration compared to the PD-L1 expression as cancer driver and gives us the opportunity to extensively review and discuss the available literature on the optimal management of PALB2-associated BC. Overall, our case report and review of the literature provide additional evidence that the germline analysis of PALB2 gene should be included in routine genetic testing for predictive purposes and to refine treatment algorithms.

Clinical risk management of breast, ovarian, pancreatic, and prostatic cancers for BRCA1/2 variant carriers in Japan

Opportunities for genetic counseling and germline BRCA1/2 (BRCA) testing are increasing in Japan owing to cancer genomic profiling testing and companion diagnostics being covered by national health insurance for patients with BRCA-related cancers. These tests are useful not only to judge whether platinum agents and PARP inhibitors are indicated but also to reveal an autosomal-dominant inherited cancer syndrome: hereditary breast and ovarian cancer. In individuals with germline BRCA variants, risk of cancers of the breast, ovary, pancreas, and prostate is significantly increased at various ages of onset, but the stomach, uterus, biliary tract, and skin might also be at risk. For women with pathogenic BRCA variants, breast awareness and image analyses should be initiated in their 20s, and risk-reducing procedures such as mastectomy are recommended starting in their 30s, with salpingo-oophorectomy in their late 30s. For male BRCA pathogenic variant carriers, prostatic surveillance should be applied using serum prostate-specific antigen starting in their 40s. For both sexes, image examinations ideally using endoscopic ultrasound and magnetic resonance cholangiopancreatography and blood testing should begin in their 50s for pancreatic surveillance. Homologous recombination pathway-associated genes are also causative candidates. Variant pathogenicity needs to be evaluated every 6-12 months when results are uncertain for clinical significance. Genetic counseling needs to be offered to the blood relatives of the pathogenic variant carriers with suitable timing. We review the recommended cross-organ BRCA risk management in Japan.

Mutations of BRCA1, BRCA2, and PALB2 Genes in Breast Tumor Tissue: Relationship with the Effectiveness of Neoadjuvant Chemotherapy and Disease Prognosis

It has been shown that the loss of function of the BRCA1, BRCA2, and PALB2 genes due to a number of hereditary mutations or chromosomal aberrations can affect the effectiveness of chemotherapy treatment and disease prognosis in patients with various types of cancer, and in particular in breast cancer. Thus, the aim of the work was to evaluate the predictive and prognostic potential of DNA copy number aberrations and mutations in the BRCA1, BRCA2, and PALB2 genes in breast tumors.

MATERIALS AND METHODS

The study included 66 patients with breast cancer. DNA copy number aberrations (CNA) were assessed by high-density CytoScanHD™ Array micro matrix analysis. Gene mutations were assessed by sequencing on the MiSeq™ Sequencing System using the Accel-Amplicon BRCA1, BRCA2, and PALB2 Panel.

RESULTS

It has been established that the presence of a normal copy number of PALB2 is associated with a lack of response to chemotherapy in Taxotere-containing treatment regimens (p = 0.05). In addition, the presence of a PALB2 deletion is associated with 100% metastatic survival rates (log-rank test p = 0.04). As a result of sequencing, 25 mutations were found in the BRCA1 gene, 42 mutations in BRCA2, and 27 mutations in the PALB2 gene. The effect of mutations on the effectiveness of treatment is controversial, but an effect on the survival of patients with breast cancer has been shown. So, in the presence of pathogenic mutations in the BRCA2 gene, 100% metastatic survival is observed (log-rank test p = 0.05), as well as in the elimination of PALB2 mutations during treatment (log-rank test p = 0.07).

CONCLUSION

Currently, there is little data on the effect of chromosomal aberrations and mutations in the BRCA1/2 and PALB2 genes on the effectiveness of treatment and prognosis of the disease. At the same time, the study of these genes has great potential for testing focused on a personalized approach to the treatment of patients with breast cancer.

Global trends in BRCA-related breast cancer research from 2013 to 2022: A scientometric analysis

Introduction

Since the mid-2000s, breast cancer incidence among women has slowly increased at about 0.5% per year. In the last three decades, Breast Cancer Susceptibility Gene (BRCA) has been proven to be the crucial gene in encouraging the incidence and development of breast cancer. However, scientometric analysis on BRCA-related breast cancer is in shortage. Thus, to have a clear understanding of the current status and catch up with the hotspots, a scientometric analysis was conducted on specific academic publications collected from the Web of Science (WoS).

Methods

We searched the Web of Science Core Collection (WoSCC) to procure associated articles as our dataset. Bibliometric, CiteSpace, VOSviewer, and HistCite software were then applied to conduct visual analyses of countries, institutions, journals, authors, landmark articles, and keywords in this research field.

Results

A total of 7,266 articles and 1,310 review articles published between 2013 to 2022 were retrieved eventually. The annual output steadily rose year by year and peaked in 2021. The USA led the way in the number of published works, total citations, and collaboration. Breast Cancer Research and Treatment was the most favoured journal in this research field. Narod SA from the University of Toronto produced the most publications. At last, the most prominent keywords were "breast cancer" (n=1,778), "women" (n=1,369), "brca1" (n=1,276), "ovarian cancer" (n=1,259), "risk" (n=1,181), and "mutations" (n=929), which exposed the hotspots within the BRCA domain of breast cancer study.

Conclusion

The tendency in the BRCA research field over the past decade was presented by the scientometric analysis. The current research focus is the clinical trials of poly-adenosine diphosphate ribose polymerase inhibitors (PARPi) drugs and their resistance mechanisms.

Uncommon variants detected via hereditary cancer panel and suggestions for genetic counseling

OBJECTIVE

Hereditary cancer syndromes constitute 5-10% of all cancers. The development of next-generation sequencing technologies has made it possible to examine many hereditary cancer syndrome-causing genes in a single panel. This study's goal was to describe the prevalence and the variant spectrum using NGS in individuals who were thought to have a hereditary predisposition for cancer.

MATERIAL AND METHOD

Analysis was performed for 1254 who were thought to have a familial predisposition for cancer. We excluded 46 patients who were carrying BRCA1/2 variants in this study, for focusing on the rare gene mutations. Sequencing was performed using the Sophia Hereditary Cancer Solution v1.1 Panel and the Qiagen Large Hereditary Cancer Panel. The Illumina MiSeq system was used for the sequencing procedure. The software used for the data analyses was Sophia DDM and QIAGEN Clinical Insight (QCITM) Analyze. The resulting genomic changes were classified according to the current guidelines of ACMG/AMP.

RESULTS

Pathogenic/likely pathogenic variants were detected in 172 (13.7%) of 1254 patients. After excluding the 46 BRCA1/2-positive patients, among the remaining 126 patients; there were 60 (4.8%) breast cancer, 33 (2.6%) colorectal cancer, 9 (0.7%) ovarian cancer, 5 (0.4%) endometrium cancer, 5 (0.4%) stomach cancer, 3 (0.2%) prostate cancer patients. The most altered genes were MUTYH in 27 (2.1%) patients, MMR genes (MLH1, MSH6, MSH, MSH2, PMS2 and EPCAM) in 26 (2%) patients, and ATM in 25 (2%) patients. We also examined the genotype-phenotype correlation in rare variants. Additionally, we identified 11 novel variations.

CONCLUSION

This study provided significant information regarding rare variants observed in the Turkish population because it was carried out with a large patient group. Personalized treatment options and genetic counseling for the patients are therefore made facilitated.

The APOBEC3B c.783delG Truncating Mutation Is Not Associated with an Increased Risk of Breast Cancer in the Polish Population

The APOBEC3B gene belongs to a cluster of DNA-editing enzymes on chromosome 22 and encodes an activation-induced cytidine deaminase. A large deletion of APOBEC3B was associated with increased breast cancer risk, but the evidence is inconclusive. To investigate whether or not APOBEC3B is a breast cancer susceptibility gene, we sequenced this gene in 617 Polish patients with hereditary breast cancer. We detected a single recurrent truncating mutation (c.783delG, p.Val262Phefs) in four of the 617 (0.65%) hereditary cases by sequencing. We then genotyped an additional 12,484 women with unselected breast cancer and 3740 cancer-free women for the c.783delG mutation. The APOBEC3B c.783delG allele was detected in 60 (0.48%) unselected cases and 19 (0.51%) controls (OR = 0.95, 95% CI 0.56-1.59, p = 0.94). The allele was present in 8 of 1968 (0.41%) familial breast cancer patients from unselected cases (OR = 0.80, 95% CI 0.35-1.83, p = 0.74). Clinical characteristics of breast tumors in carriers of the APOBEC3B mutation and non-carriers were similar. No cancer type was more frequent in the relatives of mutation carriers than in those of non-carriers. We conclude the APOBEC3B deleterious mutation p.Val262Phefs does not confer breast cancer risk. These data do not support the hypothesis that APOBEC3B is a breast cancer susceptibility gene.