Pathology of breast and ovarian cancers among BRCA1 and BRCA2 mutation carriers: results from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA)

Cis- and trans-eQTL TWASs of breast and ovarian cancer identify more than 100 susceptibility genes in the BCAC and OCAC consortia

Transcriptome-wide association studies (TWASs) have investigated the role of genetically regulated transcriptional activity in the etiologies of breast and ovarian cancer. However, methods performed to date have focused on the regulatory effects of risk-associated SNPs thought to act in cis on a nearby target gene. With growing evidence for distal (trans) regulatory effects of variants on gene expression, we performed TWASs of breast and ovarian cancer using a Bayesian genome-wide TWAS method (BGW-TWAS) that considers effects of both cis- and trans-expression quantitative trait loci (eQTLs). We applied BGW-TWAS to whole-genome and RNA sequencing data in breast and ovarian tissues from the Genotype-Tissue Expression project to train expression imputation models. We applied these models to large-scale GWAS summary statistic data from the Breast Cancer and Ovarian Cancer Association Consortia to identify genes associated with risk of overall breast cancer, non-mucinous epithelial ovarian cancer, and 10 cancer subtypes. We identified 101 genes significantly associated with risk with breast cancer phenotypes and 8 with ovarian phenotypes. These loci include established risk genes and several novel candidate risk loci, such as ACAP3, whose associations are predominantly driven by trans-eQTLs. We replicated several associations using summary statistics from an independent GWAS of these cancer phenotypes. We further used genotype and expression data in normal and tumor breast tissue from the Cancer Genome Atlas to examine the performance of our trained expression imputation models. This work represents an in-depth look into the role of trans eQTLs in the complex molecular mechanisms underlying these diseases.

Germline pathogenic variants associated with triple-negative breast cancer in US Hispanic and Guatemalan women using hospital and community-based recruitment strategies

PURPOSE

Recruit and sequence breast cancer subjects in Guatemalan and US Hispanic populations. Identify optimum strategies to recruit Latin American and Hispanic women into genetic studies of breast cancer.

METHODS

We used targeted gene sequencing to identify pathogenic variants in 19 familial breast cancer susceptibility genes in DNA from unselected Hispanic breast cancer cases in the US and Guatemala. Recruitment across the US was achieved through community-based strategies. In addition, we obtained patients receiving cancer treatment at major hospitals in Texas and Guatemala.

RESULTS

We recruited 287 Hispanic US women, 38 (13%) from community-based and 249 (87%) from hospital-based strategies. In addition, we ascertained 801 Guatemalan women using hospital-based recruitment. In our experience, a hospital-based approach was more efficient than community-based recruitment. In this study, we sequenced 103 US and 137 Guatemalan women and found 11 and 10 pathogenic variants, respectively. The most frequently mutated genes were BRCA1, BRCA2, CHEK2, and ATM. In addition, an analysis of 287 US Hispanic patients with pathology reports showed a significantly higher percentage of triple-negative disease in patients with pathogenic variants (41% vs. 15%). Finally, an analysis of mammography usage in 801 Guatemalan patients found reduced screening in women with a lower socioeconomic status (p < 0.001).

CONCLUSION

Guatemalan and US Hispanic women have rates of hereditary breast cancer pathogenic variants similar to other populations and are more likely to have early age at diagnosis, a family history, and a more aggressive disease. Patient recruitment was higher using hospital-based versus community enrollment. This data supports genetic testing in breast cancer patients to reduce breast cancer mortality in Hispanic women.

Timing of genetic testing in BRCA1/2 and PALB2-Associated breast cancer: Preoperative result disclosure increases uptake of risk-reducing mastectomy and reduces unnecessary exposure to radiotherapy

INTRODUCTION

The impact of timing of genetic testing on uptake of risk reducing mastectomy (RRM) in affected female BRCA1/2 or PALB2 carriers remains an area of evolving interest, particularly with the introduction of mainstream genetic testing initiatives.

METHODS

Women with stage I-III breast cancer and a confirmed germline pathogenic variant in BRCA1/2 or PALB2 between 2000 and 2023 were identified from an institutional genetics database. Uptake of RRM was evaluated according to disclosure of genetic testing results before or after index surgery for a first diagnosis of breast cancer.

RESULTS

The cohort included 287 female BRCA1/2 or PALB2 carriers with a median age of 44 years (IQR, 36-52). Overall, 155 (54 %) carriers received genetic testing results before and 132 (46 %) after index breast surgery. Receipt of genetic testing results before surgery was associated with a higher rate of index bilateral mastectomy (58.7 % vs. 7.6 %, p < 0.001) and a commensurate decrease in adjuvant radiation (41.9 % vs. 74.2 %, p < 0.001). At a median follow up of 4.4 years after genetic testing, 219 (76.3 %) affected carriers had undergone bilateral RRM, including 83.9 % with preoperative knowledge and 67.4 % of patients with postoperative knowledge of their germline pathogenic variant (log rank, p < 0.001). On multivariate regression, disclosure of genetic testing results before index breast surgery was independently associated with long-term uptake of bilateral mastectomy (HR 1.69, 95 % CI 1.21-2.38).

CONCLUSION

Genetic testing results delivered prior to index breast surgery increase uptake of bilateral RRM in affected BRCA1/2 and PALB2 carriers. Efforts to mainstream genetic testing would help optimize surgical decision-making.

Improving the Lives of Women With Ovarian Cancer

Being a gynecologic oncologist is a privilege. Women with cancer address their challenges with grit and resilience. Their most basic questions motivated my career-long search for scientific answers hidden in genetics, novel therapeutics, and cancer prevention. But medicine is a team sport. Working alongside gifted colleagues and mentoring trainees to assume starring roles on the team has sustained and enriched my career. Advocating for patients and the specialty of gynecologic oncology provided another means to advance research and cancer awareness to improve patient outcomes. The author believe the most exciting times are yet to come.

What Proportion of BRCA-Associated Breast Cancer Is Human Epidermal Growth Factor 2-Low and Eligible for Additional Targeted Therapy?

INTRODUCTION

DESTINY B04 provided clinical meaning to a new classification of human epidermal growth factor 2 (HER2) expression in breast cancer: HER2-low. Patients with germline breast cancer type 1 gene pathogenic variants (gBRCA1) often develop triple negative breast cancer (TNBC), but the proportion who could be classified as HER2-low and qualify for an additional targeted therapy option is unknown. This study aims to characterize the proportion of gBRCA1 or germline breast cancer type 2 gene pathogenic variants patients for whom these novel targeted therapies may be an option.

METHODS

We performed a retrospective chart review of patients with gBRCA1/2 treated at our institution for invasive breast cancer from 2000 to 2021. Synchronous or metachronous contralateral breast cancers were recorded separately. HER2 status was determined by immunohistochemistry and fluorescence in situ hybridization. We excluded patients without complete HER2 data.

RESULTS

Among the 95 breast cancers identified in our cohort of 85 gBRCA1/2 patients, 41 (43%) were TNBC, 38 (40%) were hormone receptor positive (HR+)/HER2-negative, and 16 (17%) were HER2-positive based on standard conventions. We found that 82% of the HR+/HER2-cancers and 66% of TNBCs would be reclassified as HER2-low. After stratifying by BRCA gene status, 64% of cancers in patients with gBRCA1 and 58% of cancers in patients with germline breast cancer type 2 gene pathogenic variants were HER2-low.

CONCLUSIONS

A significant portion of gBRCA1/2 patients who were previously diagnosed with TNBC or HR+/HER2- breast cancer would now be classified as HER2-low and could be considered for the use of trastuzumab deruxtecan in the metastatic setting. Outcome differences from therapy changes in this cohort should now be assessed.

PARP Inhibitors for Breast Cancer Treatment: A Review

Importance

Poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors have revolutionized the treatment of patients with germline BRCA1/2-associated breast cancer, representing the first targeted therapy capable of improving outcomes in patients with hereditary tumors. However, resistance to PARP inhibitors occurs in almost all patients.

Observations

This narrative review summarizes the biological rationale behind the use of PARP inhibitors in breast cancer, as well as the available evidence, recent progress, and potential future applications of these agents. Recent studies have shown that the benefit of PARP inhibitors extends beyond patients with germline BRCA1/2-associated metastatic breast cancer to patients with somatic BRCA1/2 variants and to those with germline PALB2 alterations. Moreover, these agents proved to be effective both in the metastatic and adjuvant settings. However, patients with metastatic breast cancer usually do not achieve the long-term benefit from PARP inhibitors observed in other tumor types. Mechanisms of resistance have been identified, but how to effectively target them is largely unknown. Ongoing research is investigating both novel therapeutics and new combination strategies to overcome resistance. PARP1-selective inhibitors, by sparing the hematological toxic effects induced by the PARP2 blockade, are promising agents to be combined with chemotherapy, antibody-drug conjugates, and other targeted therapies.

Conclusions and Relevance

Although the efficacy of PARP inhibitors is well established, many questions persist. Future research should focus on identifying predictive biomarkers and therapeutic strategies to overcome resistance. Integrating well-designed translational efforts into all clinical studies is thereby crucial to laying the groundwork for future insights from ongoing research.

BRCA testing and management of BRCA-mutated early-stage breast cancer: a comprehensive statement by expert group from GCC region

BReast CAncer (BRCA)1 and BRCA2 gene pathogenic variants account for most hereditary breast cancers (BC). Identification of BRCA mutations can significantly influence both prognosis and treatment outcomes. Furthermore, it enables the identification of individuals who are at heightened risk of developing BC due to inherited genetic mutations. Many developing countries rely on western guidelines for BRCA testing and BC management; however, there exist wide disparities in the prevalence of risk factors, availability of medical resources, and practice patterns. Guidelines tailored to specific regions can help mitigate healthcare variations, promote consistency in treatment, and aid healthcare providers in identifying effective therapies for improving patient outcomes. Hence, oncologists from the Gulf Cooperation Council (GCC) congregated virtually in March 2023 and reviewed existing data on the epidemiology of BC, BRCA mutations, practices and challenges associated with BRCA testing and management of BRCA mutated early-stage BC in the GCC region. They also provided insights on the real-world diagnostic and treatment practices and challenges in the GCC region in the BRCA-mutated early-stage BC domain and suggested some variations to international guidelines to aid their uptake in this region.

HR-positive/HER2-negative breast cancer arising in patients with or without BRCA2 mutation: different biological phenotype and similar prognosis

Background

BRCA2 plays a key role in homologous recombination. However, information regarding its mutations in Chinese patients with breast cancer remains limited.

Objectives

This study aimed to assess the clinicopathological characteristics of BRCA2 mutation breast cancer and explore the mutation's effect on hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer survival in China.

Design

This hospital-based cohort study prospectively included 629 women with breast cancer diagnosed from 2008 to 2023 at Zhejiang Cancer Hospital in China.

Methods

We compared the clinicopathological characteristics and metastatic patterns and analysed the invasive disease-free survival (iDFS), distant relapse-free survival (DRFS) and first-line progression-free survival (PFS1) of patients with HR-positive/HER2-negative breast cancer according to BRCA2 mutations.

Results

Among the 629 patients, 78 had BRCA2 mutations (12.4%) and 551 did not (87.6%). The mean age at diagnosis was lower in the BRCA2 mutation breast cancer group than in the non-mutation breast cancer group (38.91 versus 41.94 years, p = 0.016). BRCA2 mutation breast cancers were more likely to be lymph node-positive than non-mutation breast cancers (73.0% versus 56.6%, p = 0.037). The pathological grade was higher in 47.1% of BRCA2 mutation breast cancers than in 29.6% of non-mutation breast cancers (p = 0.014). The proportions of patients with BRCA2 mutations who developed contralateral breast cancer (19.2% versus 8.8%, p = 0.004), breast cancer in the family (53.8% versus 38.3%, p = 0.009) and ovarian cancer in the family (7.6% versus 2.4%, p = 0.022) were higher than those of patients without the mutation. The median follow-up time was 92.78 months. Multivariate analysis showed that BRCA2 mutation was not associated with poorer iDFS [hazard ratio = 0.9, 95% confidence interval (CI) = 0.64-1.27, p = 0.56] and poorer distant relapse-free survival (DRFS) (hazard ratio = 1.09, 95% CI = 0.61-1.93, p = 0.76). There was no significant difference between the two groups with regard to metastatic patterns in the advanced disease setting. In the first-line metastatic breast cancer setting, PFS1 expression was broadly similar between the two groups irrespective of chemotherapy or endocrine therapy.

Conclusion

HR-positive/HER2-negative breast cancer with BRCA2 mutations differs from those without mutations in clinical behaviour and reflects more aggressive tumour behaviour. Our results indicate that BRCA2 mutations have no significant effect on the survival of Chinese women with HR-positive/HER2-negative breast cancer.

Risk Factors for Ovarian Cancer by BRCA Status: A Collaborative Case-Only Analysis

BACKGROUND

Women with an inherited pathogenic variant in BRCA1 or BRCA2 have a greatly increased risk of developing ovarian cancer, but the importance of behavioral factors is less clear. We used a case-only design to compare the magnitude of associations with established reproductive, hormonal, and lifestyle risk factors between BRCA mutation carriers and noncarriers.

METHODS

We pooled data from five studies from the Ovarian Cancer Association Consortium including 637 BRCA carriers and 4,289 noncarriers. Covariate-adjusted generalized linear mixed models were used to estimate interaction risk ratios (IRR) and 95% confidence intervals (CI), with BRCA (carrier vs. noncarrier) as the response variable.

RESULTS

IRRs were above 1.0 for known protective factors including ever being pregnant (IRR = 1.29, 95% CI; 1.00-1.67) and ever using the oral contraceptive pill (1.30, 95% CI; 1.07-1.60), suggesting the protective effects of these factors may be reduced in carriers compared with noncarriers. Conversely, the IRRs for risk factors including endometriosis and menopausal hormone therapy were below 1.0, suggesting weaker positive associations among BRCA carriers. In contrast, associations with lifestyle factors including smoking, physical inactivity, body mass index, and aspirin use did not appear to differ by BRCA status.

CONCLUSIONS

Our results suggest that associations with hormonal and reproductive factors are generally weaker for those with a pathogenic BRCA variant than those without, while associations with modifiable lifestyle factors are similar for carriers and noncarriers.

IMPACT

Advice to maintain a healthy weight, be physically active, and refrain from smoking will therefore benefit BRCA carriers as well as noncarriers.

Postpartum Breast Cancer and Survival in Women With Germline BRCA Pathogenic Variants

Importance

In young-onset breast cancer (YOBC), a diagnosis within 5 to 10 years of childbirth is associated with increased mortality. Women with germline BRCA1/2 pathogenic variants (PVs) are more likely to be diagnosed with BC at younger ages, but the impact of childbirth on mortality is unknown.

Objective

To determine whether time between most recent childbirth and BC diagnosis is associated with mortality among patients with YOBC and germline BRCA1/2 PVs.

Design, Setting, and Participants

This prospective cohort study included women with germline BRCA1/2 PVs diagnosed with stage I to III BC at age 45 years or younger between 1950 and 2021 in the United Kingdom, who were followed up until November 2021. Data were analyzed from December 3, 2021, to November 29, 2023.

Exposure

Time between most recent childbirth and subsequent BC diagnosis, with recent childbirth defined as 0 to less than 10 years, further delineated to 0 to less than 5 years and 5 to less than 10 years.

Main Outcomes and Measures

The primary outcome was all-cause mortality, censored at 20 years after YOBC diagnosis. Mortality of nulliparous women was compared with the recent post partum groups and the 10 or more years post partum group. Cox proportional hazards regression analyses were adjusted for age, tumor stage, and further stratified by tumor estrogen receptor (ER) and BRCA gene status.

Results

Among 903 women with BRCA PVs (mean [SD] age at diagnosis, 34.7 [6.1] years; mean [SD] follow-up, 10.8 [9.8] years), 419 received a BC diagnosis 0 to less than 10 years after childbirth, including 228 women diagnosed less than 5 years after childbirth and 191 women diagnosed 5 to less than 10 years after childbirth. Increased all-cause mortality was observed in women diagnosed within 5 to less than 10 years post partum (hazard ratio [HR], 1.56 [95% CI, 1.05-2.30]) compared with nulliparous women and women diagnosed 10 or more years after childbirth, suggesting a transient duration of postpartum risk. Risk of mortality was greater for women with ER-positive BC in the less than 5 years post partum group (HR, 2.35 [95% CI, 1.02-5.42]) and ER-negative BC in the 5 to less than 10 years post partum group (HR, 3.12 [95% CI, 1.22-7.97]) compared with the nulliparous group. Delineated by BRCA1 or BRCA2, mortality in the 5 to less than 10 years post partum group was significantly increased, but only for BRCA1 carriers (HR, 2.03 [95% CI, 1.15-3.58]).

Conclusions and Relevance

These findings suggest that YOBC with germline BRCA PVs was associated with increased risk for all-cause mortality if diagnosed within 10 years after last childbirth, with risk highest for ER-positive BC diagnosed less than 5 years post partum, and for ER-negative BC diagnosed 5 to less than 10 years post partum. BRCA1 carriers were at highest risk for poor prognosis when diagnosed at 5 to less than 10 years post partum. No such associations were observed for BRCA2 carriers. These results should inform genetic counseling, prevention, and treatment strategies for BRCA PV carriers.

Spatial Transcriptomics Suggests That Alterations Occur in the Preneoplastic Breast Microenvironment of BRCA1/2 Mutation Carriers

Breast cancer is the most common cancer in females, affecting one in every eight women and accounting for the majority of cancer-related deaths in women worldwide. Germline mutations in the BRCA1 and BRCA2 genes are significant risk factors for specific subtypes of breast cancer. BRCA1 mutations are associated with basal-like breast cancers, whereas BRCA2 mutations are associated with luminal-like disease. Defects in mammary epithelial cell differentiation have been previously recognized in germline BRCA1/2 mutation carriers even before cancer incidence. However, the underlying mechanism is largely unknown. Here, we employ spatial transcriptomics to investigate defects in mammary epithelial cell differentiation accompanied by distinct microenvironmental alterations in preneoplastic breast tissues from BRCA1/2 mutation carriers and normal breast tissues from noncarrier controls. We uncovered spatially defined receptor-ligand interactions in these tissues for the investigation of autocrine and paracrine signaling. We discovered that β1-integrin-mediated autocrine signaling in BRCA2-deficient mammary epithelial cells may differ from BRCA1-deficient mammary epithelial cells. In addition, we found that the epithelial-to-stromal paracrine signaling in the breast tissues of BRCA1/2 mutation carriers is greater than in control tissues. More integrin-ligand pairs were differentially correlated in BRCA1/2-mutant breast tissues than noncarrier breast tissues with more integrin receptor-expressing stromal cells.

IMPLICATIONS

These results suggest alterations in the communication between mammary epithelial cells and the microenvironment in BRCA1 and BRCA2 mutation carriers, laying the foundation for designing innovative breast cancer chemo-prevention strategies for high-risk patients.

Gender-Specific Genetic Predisposition to Breast Cancer: BRCA Genes and Beyond

Among neoplastic diseases, breast cancer (BC) is one of the most influenced by gender. Despite common misconceptions associating BC as a women-only disease, BC can also occur in men. Additionally, transgender individuals may also experience BC. Genetic risk factors play a relevant role in BC predisposition, with important implications in precision prevention and treatment. The genetic architecture of BC susceptibility is similar in women and men, with high-, moderate-, and low-penetrance risk variants; however, some sex-specific features have emerged. Inherited high-penetrance pathogenic variants (PVs) in BRCA1 and BRCA2 genes are the strongest BC genetic risk factor. BRCA1 and BRCA2 PVs are more commonly associated with increased risk of female and male BC, respectively. Notably, BRCA-associated BCs are characterized by sex-specific pathologic features. Recently, next-generation sequencing technologies have helped to provide more insights on the role of moderate-penetrance BC risk variants, particularly in PALB2, CHEK2, and ATM genes, while international collaborative genome-wide association studies have contributed evidence on common low-penetrance BC risk variants, on their combined effect in polygenic models, and on their role as risk modulators in BRCA1/2 PV carriers. Overall, all these studies suggested that the genetic basis of male BC, although similar, may differ from female BC. Evaluating the genetic component of male BC as a distinct entity from female BC is the first step to improve both personalized risk assessment and therapeutic choices of patients of both sexes in order to reach gender equality in BC care. In this review, we summarize the latest research in the field of BC genetic predisposition with a particular focus on similarities and differences in male and female BC, and we also discuss the implications, challenges, and open issues that surround the establishment of a gender-oriented clinical management for BC.

Counselling Framework for Germline BRCA1/2 and PALB2 Carriers Considering Risk-Reducing Mastectomy

Female BRCA1/2 and PALB2 germline pathogenic variant carriers have an increased lifetime risk of breast cancer and may wish to consider risk-reducing mastectomy (RRM) for surgical prevention. Quantifying the residual lifetime risk and absolute benefit from RRM requires careful consideration of a patient's age, pathogenic variant, and their personal history of breast or ovarian cancer. Historically, patients have been counselled that RRM does not necessarily prolong survival relative to high-risk surveillance, although recent studies suggest a possible survival benefit of RRM in BRCA1 carriers. The uptake of RRM has increased dramatically over the last several decades yet varies according to sociodemographic factors and geographic region. The increased adoption of nipple-sparing mastectomy techniques, ability to avoid axillary staging, and availability of reconstructive options for most germline pathogenic variant carriers has helped to minimize the morbidity of RRM. Preoperative discussions should include evidence regarding postmastectomy sensation, the potential for supplemental surgery, pregnancy-related chest wall changes, and the need for continued clinical surveillance. Approaches that include sensation preservation and robotic nipple-sparing mastectomy are an area of evolving research that may be more widely adopted in the future.

ER-positive and BRCA2-mutated breast cancer: a literature review

BRCA2-mutated carriers have a high lifetime risk of breast cancer (BC), an early age of onset, and an increased risk of other cancers (including ovarian, pancreatic, and prostate cancer). Almost 70-80% of BRCA2-mutated BC are estrogen receptor (ER)-positive, which is a particular type of ER-positive BC that differs from sporadic ER-positive BC. This article reviews the clinicopathological features, treatment, and prognosis of ER-positive and BRCA2-mutated BC to provide a reference for clinical decision-making.

Expression and Localization of Ferritin-Heavy Chain Predicts Recurrence for Breast Cancer Patients with a BRCA1/2 Mutation

The ferritin-heavy chain (FTH1) is the catalytic subunit of the ferroxidase ferritin, which prevents oxidative DNA damage via intracellular iron storage. FTH1 was shown to be a prognostic marker for triple-negative breast cancer (BC) patients and associated with an enrichment of CD8+ effector T cells. However, whether the expression and localization of FTH1 are also associated with clinical outcome in other BC subtypes is unknown. Here, we investigated the association of FTH1 with time to survival in BCs from 222 BRCA1/2 mutation carriers by immunohistochemistry on tissue microarrays. In addition, for 51 of these patients, the association between FTH1 and specific subsets of T cells was evaluated on whole slides using automatic scoring algorithms. We revealed that nuclear FTH1 (nFTH1) expression, in multivariable analyses, was associated with a shorter disease-free (HR = 2.71, 95% CI = 1.49-4.92, p = 0.001) and metastasis-free survival (HR = 3.54, 95% CI = 1.45-8.66, p = 0.006) in patients carrying a BRCA1/2 mutation. However, we found no relation between cytoplasmic FTH1 expression and survival of BRCA1/2 mutation carriers. Moreover, we did not detect an association between FTH1 expression and the amount of CD45+ (p = 0.13), CD8+ (p = 0.18), CD4+ (p = 0.20) or FOXP3+ cells (p = 0.17). Consequently, the mechanism underlying the worse recurrence-free survival of nFTH1 expression in BRCA1/2 mutation carriers needs further investigation.

Synchronous and Metachronous Breast and Ovarian Cancers: Experience from a Single Tertiary Care Cancer Centre in India

Women with either breast cancer (BC) or ovarian cancer (OC) have a 1.5-2 times higher risk of developing the other. Discerning discrete primaries versus metastases from either can be challenging. Clinico-pathological and outcome details of patients diagnosed with both BC and OC from December 1994 to August 2018 were retrospectively evaluated at a single tertiary cancer centre. We report the pattern of presentation and recurrences with case-based illustrations. Out of 139 patients, presentation was BC-first in 66.2%, OC-first in 24.5% and synchronous cancers (SC) in 9.3% of women. The median age at diagnosis in BC-first, OC-first and SC was 42 years, 48 years and 49 years, respectively. The most common histological subtype was invasive breast carcinoma-no special type (74.8%) in BC and serous cystadenocarcinoma (81.3%) in OC. BC presented at an early stage in 67.6% while OC presented at an advanced stage in 48.2% of patients. Germline mutation results were available in 82% with 61.4% of the cohort exhibiting a mutation- BRCA1 mutation being the most common. The median time to development of second cancer was 77.4 months and 39.4 months in BC-first and OC-first, respectively. At a median follow-up of 9.47 years, disease-free survival was 32.6%, 32.4% and 30.8% in BC-first, OC-first and SC, respectively (p < 0.001). In hereditary breast and ovarian cancer, BC-first patients have a better prognosis while synchronous malignancies have worse oncological outcomes. Deaths are mainly due to OC progression. Appropriate surveillance and prophylactic intervention in young patients with breast cancer may improve overall outcomes.

Estrogen receptor-positive breast cancer and adverse outcome in BRCA2 mutation carriers and young non-carrier patients

Estrogen receptor-positive (ER+) breast cancer generally confers a more favorable prognosis than ER-negative cancer, however, a different picture is emerging for BRCA2 mutation carriers and young patients. We used nationwide data from population-based registries to study prognostic effects in those two groups. Of all 2817 eligible women diagnosed with breast cancer in Iceland during 1980-2004, 85% had been tested for the Icelandic 999del5 BRCA2 (c.771_775delTCAAA) founder pathogenic variant. We compared breast cancer-specific survival, effects of ER status, other clinical parameters, and treatment, between three mutually exclusive groups: BRCA2-carriers, non-carriers diagnosed 40 years or younger, and older non-carriers. Prevalence of the BRCA2 mutation among tested patients <=40 years of age was 21.0%, but it was 5.4% among women diagnosed >40 years of age. For ER+ cancer, breast cancer-specific 15-year survival was 49.7%, 55.2%, and 74.7%, among BRCA2-carriers, young and older non-carriers, respectively, whereas for ER-negative cancer, survival was similar (64.0-69.3%) for all three groups. Neither BRCA2 carriers nor young non-carriers did tumor grade 3 predict worse survival than did tumor grade 1. The adverse outcome for the young cases cannot be explained by BRCA2 mutations, as carriers were excluded from the group. Those two clinically important patient groups need special attention with respect to treatment choices, in particular, if diagnosed with ER+ tumors. It is thus advisable to have knowledge of BRCA2 status when treatment decisions are made. Finally, it is important to understand the biological basis for the specific nature of ER+ tumors in young women and BRCA2 carriers.

Cis- and trans-eQTL TWAS of breast and ovarian cancer identify more than 100 risk associated genes in the BCAC and OCAC consortia

Transcriptome-wide association studies (TWAS) have investigated the role of genetically regulated transcriptional activity in the etiologies of breast and ovarian cancer. However, methods performed to date have only considered regulatory effects of risk associated SNPs thought to act in cis on a nearby target gene. With growing evidence for distal (trans) regulatory effects of variants on gene expression, we performed TWAS of breast and ovarian cancer using a Bayesian genome-wide TWAS method (BGW-TWAS) that considers effects of both cis- and trans-expression quantitative trait loci (eQTLs). We applied BGW-TWAS to whole genome and RNA sequencing data in breast and ovarian tissues from the Genotype-Tissue Expression project to train expression imputation models. We applied these models to large-scale GWAS summary statistic data from the Breast Cancer and Ovarian Cancer Association Consortia to identify genes associated with risk of overall breast cancer, non-mucinous epithelial ovarian cancer, and 10 cancer subtypes. We identified 101 genes significantly associated with risk with breast cancer phenotypes and 8 with ovarian phenotypes. These loci include established risk genes and several novel candidate risk loci, such as ACAP3, whose associations are predominantly driven by trans-eQTLs. We replicated several associations using summary statistics from an independent GWAS of these cancer phenotypes. We further used genotype and expression data in normal and tumor breast tissue from the Cancer Genome Atlas to examine the performance of our trained expression imputation models. This work represents a first look into the role of trans-eQTLs in the complex molecular mechanisms underlying these diseases.

Reevaluating the Role of Progesterone in Ovarian Cancer: Is Progesterone Always Protective?

Ovarian cancer (OC) represents a collection of rare but lethal gynecologic cancers where the difficulty of early detection due to an often-subtle range of abdominal symptoms contributes to high fatality rates. With the exception of BRCA1/2 mutation carriers, OC most often manifests as a post-menopausal disease, a time in which the ovaries regress and circulating reproductive hormones diminish. Progesterone is thought to be a "protective" hormone that counters the proliferative actions of estrogen, as can be observed in the uterus or breast. Like other steroid hormone receptor family members, the transcriptional activity of the nuclear progesterone receptor (nPR) may be ligand dependent or independent and is fully integrated with other ubiquitous cell signaling pathways often altered in cancers. Emerging evidence in OC models challenges the singular protective role of progesterone/nPR. Herein, we integrate the historical perspective of progesterone on OC development and progression with exciting new research findings and critical interpretations to help paint a broader picture of the role of progesterone and nPR signaling in OC. We hope to alleviate some of the controversy around the role of progesterone and give insight into the importance of nPR actions in disease progression. A new perspective on the role of progesterone and nPR signaling integration will raise awareness to the complexity of nPRs and nPR-driven gene regulation in OC, help to reveal novel biomarkers, and lend critical knowledge for the development of better therapeutic strategies.

Contribution of constitutional BRCA1 promoter methylation to early-onset and familial breast cancer patients from Pakistan

PURPOSE

Constitutional BRCA1 promoter methylation has been identified as a potential risk factor for breast cancer (BC) in the Caucasian population. However, this data is lacking for BC patients of Asian origin. Therefore, we assessed the contribution of constitutional BRCA1 promoter methylation in Pakistani BC patients.

METHODS

A total of 385 BRCA1/2-negative index BC patients (197 early-onset BC (≤ 30 years), 152 familial BC, 17 familial BC and ovarian cancer, 19 male BC) and 107 healthy controls were screened for the constitutional BRCA1 promoter methylation by methylation-sensitive high-resolution melting assay. Overall, 131 patients displayed triple-negative BC (TNBC) and 254 non-TNBC phenotypes. The prevalence of BRCA1 promoter methylation was calculated based on clinicopathological characteristics using univariable and multivariable logistic regression models.

RESULTS

Constitutional BRCA1 promoter methylation was identified in 19.5% (75/385) of BC patients and 13.1% (14/107) of controls. The frequency of methylation was higher in early-onset BC (23.4% vs. 13.1%, P = 0.035) and TNBC patients (29.0% vs. 13.1%, P = 0.004) compared to controls. Methylation was also more prevalent in patients with high-grade than low-grade tumors (21.7% vs. 12.2%, P = 0.034) and progesterone receptor (PR)-negative than PR-positive tumors (26.0% vs. 13.9%, P = 0.004). Constitutional BRCA1 promoter methylation remained independently associated with TNBC phenotype (odds ratio 1.99; 95% CI 1.12-3.54; P = 0.02) after adjusting for BC diagnosis age, tumor grade, ER, and PR status.

CONCLUSION

Constitutional BRCA1 promoter methylation is associated with TNBC and can serve as a non-invasive blood-based biomarker for Pakistani TNBC patients.

Neoadjuvant Talazoparib in Patients With Germline BRCA1/2 Mutation-Positive, Early-Stage Triple-Negative Breast Cancer: Results of a Phase II Study

BACKGROUND

The undetermined efficacy of the current standard-of-care neoadjuvant treatment, anthracycline/platinum-based chemotherapy, in patients with early-stage triple-negative breast cancer (TNBC) and germline BRCA mutations emphasizes the need for biomarker-targeted treatment, such as poly(ADP-ribose) polymerase inhibitors, in this setting. This phase II, single-arm, open-label study evaluated the efficacy and safety of neoadjuvant talazoparib in patients with germline BRCA1/2-mutated early-stage TNBC.

PATIENTS AND METHODS

Patients with germline BRCA1/2-mutated early-stage TNBC received talazoparib 1 mg once daily for 24 weeks (0.75 mg for moderate renal impairment) followed by surgery. The primary endpoint was pathologic complete response (pCR) by independent central review (ICR). Secondary endpoints included residual cancer burden (RCB) by ICR. Safety and tolerability of talazoparib and patient-reported outcomes were assessed.

RESULTS

Of 61 patients, 48 received ≥80% talazoparib doses, underwent surgery, and were assessed for pCR or progressed before pCR assessment and considered nonresponders. pCR rate was 45.8% (95% confidence interval [CI], 32.0%-60.6%) and 49.2% (95% CI, 36.7%-61.6%) in the evaluable and intent-to-treat (ITT) population, respectively. RCB 0/I rate was 45.8% (95% CI, 29.4%-63.2%) and 50.8% (95% CI, 35.5%-66.0%) in the evaluable and ITT population, respectively. Treatment-related adverse events (TRAE) were reported in 58 (95.1%) patients. Most common grade 3 and 4 TRAEs were anemia (39.3%) and neutropenia (9.8%). There was no clinically meaningful detriment in quality of life. No deaths occurred during the reporting period; 2 deaths due to progressive disease occurred during long-term follow-up (>400 days after first dose).

CONCLUSIONS

Neoadjuvant talazoparib monotherapy was active despite pCR rates not meeting the prespecified threshold; these rates were comparable to those observed with combination anthracycline- and taxane-based chemotherapy regimens. Talazoparib was generally well tolerated.

CLINICALTRIALS.GOV IDENTIFIER

NCT03499353.

Analysis of Turkish Breast Cancer Patients With ATM-Heterozygous Germline Mutation According to Clinicopathological Features

OBJECTIVE

The ATM gene is one of the most common breast cancer (BC) susceptibility genes after BRCA1/2 and has been shown to be a moderate BC susceptibility gene. The association between ATM germline mutation and clinical features of BC is now unknown. In this article, clinicopathological features of BC patients with ATM germline heterozygous mutation were investigated.

MATERIALS AND METHODS

Patients admitted to the Medical Genetics department of a tertiary hospital between January 2020 and December 2022 were examined. Only invasive BC patients with pathogenic mutation, likely pathogenic mutation, or variants of uncertain significance (VUS) were included in the study.

RESULTS

In all, 121 patients were included in the study. The median age at the first cancer diagnosis of the patients was 44 years. Of the total number of patients, 75.2% (91) had the histological subtype of infiltrating ductal carcinoma, and 43% (52) had Luminal B molecular subtype features. At a median follow-up of 16 months, 5.8% (7) of patients developed cancer in the contralateral breast. In addition, 7.4% (9) of the patients developed a second primary cancer during follow-up. When the patients were compared according to ATM variant classification, the localization, histologic types, and molecular subtypes of the BC were not different between all groups (respectively; p=0.68, p=0.65, p=0.32).

CONCLUSIONS

To the best of our knowledge, this is the first publication that evaluates the clinical and pathological characteristics of BC patients with germline heterozygous ATM mutations in the Turkish population. When patients were compared according to variant classifications of ATM mutation, patients' histological and molecular subtypes were similar.

Triple-Negative Breast Cancer: Histopathologic Features, Genomics, and Treatment

Triple-negative breast cancer (TNBC) is a heterogeneous and aggressive group of tumors that are defined by the absence of estrogen and progesterone receptors and lack of ERBB2 (formerly HER2 or HER2/neu) overexpression. TNBC accounts for 8%-13% of breast cancers. In addition, it accounts for a higher proportion of breast cancers in younger women compared with those in older women, and it disproportionately affects non-Hispanic Black women. TNBC has high metastatic potential, and the risk of recurrence is highest during the 5 years after it is diagnosed. TNBC exhibits benign morphologic imaging features more frequently than do other breast cancer subtypes. Mammography can be suboptimal for early detection of TNBC owing to factors that include the fast growth of this cancer, increased mammographic density in young women, and lack of the typical features of malignancy at imaging. US is superior to mammography for TNBC detection, but benign-appearing features can lead to misdiagnosis. Breast MRI is the most sensitive modality for TNBC detection. Most cases of TNBC are treated with neoadjuvant chemotherapy, followed by surgery and radiation. MRI is the modality of choice for evaluating the response to neoadjuvant chemotherapy. Survival rates for individuals with TNBC are lower than those for persons with hormone receptor-positive and human epidermal growth factor receptor 2-positive cancers. The 5-year survival rates for patients with localized, regional, and distant disease at diagnosis are 91.3%, 65.8%, and 12.0%, respectively. The early success of immunotherapy has raised hope regarding the development of personalized strategies to treat TNBC. Imaging and tumor biomarkers are likely to play a crucial role in the prediction of TNBC treatment response and TNBC patient survival in the future. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

DCIS and LCIS: Are the Risk Factors for Developing In Situ Breast Cancer Different?

Ductal carcinoma in situ (DCIS) is widely accepted as a precursor of invasive ductal carcinoma (IDC). Lobular carcinoma in situ (LCIS) is considered a risk factor for invasive lobular carcinoma (ILC), and it is unclear whether LCIS is also a precursor. Therefore, it would be expected that similar risk factors predispose to both DCIS and IDC, but not necessarily LCIS and ILC. This study examined associations with risk factors using data from 3075 DCIS cases, 338 LCIS cases, and 1584 controls aged 35-60, recruited from the UK-based GLACIER and ICICLE case-control studies between 2007 and 2012. Analysis showed that breastfeeding in parous women was protective against DCIS and LCIS, which is consistent with research on invasive breast cancer (IBC). Additionally, long-term use of HRT in post-menopausal women increased the risk of DCIS and LCIS, with a stronger association in LCIS, similar to the association with ILC. Contrary to findings with IBC, parity and the number of births were not protective against DCIS or LCIS, while oral contraceptives showed an unexpected protective effect. These findings suggest both similarities and differences in risk factors for DCIS and LCIS compared to IBC and that there may be justification for increased breast surveillance in post-menopausal women taking long-term HRT.

Homologous Recombination Deficiency Across Subtypes of Primary Breast Cancer

PURPOSE

Homologous recombination deficiency (HRD) is highly prevalent in triple-negative breast cancer (TNBC) and associated with response to PARP inhibition (PARPi). Here, we studied the prevalence of HRD in non-TNBC to assess the potential for PARPi in a wider group of patients with breast cancer.

METHODS

HRD status was established using targeted gene panel sequencing (360 genes) and BRCA1 methylation analysis of pretreatment biopsies from 201 patients with primary breast cancer in the phase II PETREMAC trial (ClinicalTrials.gov identifier: NCT02624973). HRD was defined as mutations in BRCA1, BRCA2, BRIP1, BARD1, or PALB2 and/or promoter methylation of BRCA1 (strict definition; HRD-S). In secondary analyses, a wider definition (HRD-W) was used, examining mutations in 20 additional genes. Furthermore, tumor BRCAness (multiplex ligation-dependent probe amplification), PAM50 subtyping, RAD51 nuclear foci to test functional HRD, tumor-infiltrating lymphocyte (TIL), and PD-L1 analyses were performed.

RESULTS

HRD-S was present in 5% of non-TNBC cases (n = 9 of 169), contrasting 47% of the TNBC tumors (n = 15 of 32). HRD-W was observed in 23% of non-TNBC (n = 39 of 169) and 59% of TNBC cases (n = 19 of 32). Of 58 non-TNBC and 30 TNBC biopsies examined for RAD51 foci, 4 of 4 (100%) non-TNBC and 13 of 14 (93%) TNBC cases classified as HRD-S had RAD51 low scores. In contrast, 4 of 17 (24%) non-TNBC and 15 of 19 (79%) TNBC biopsies classified as HRD-W exhibited RAD51 low scores. Of nine non-TNBC tumors with HRD-S status, only one had a basal-like PAM50 signature. There was a high concordance between HRD-S and either BRCAness, high TIL density, or high PD-L1 expression (each P < .001).

CONCLUSION

The prevalence of HRD in non-TNBC suggests that therapy targeting HRD should be evaluated in a wider breast cancer patient population. Strict HRD criteria should be implemented to increase diagnostic precision with respect to functional HRD.

Diverse genetic spectrum among patients who met the criteria of hereditary breast, ovarian and pancreatic cancer syndrome

OBJECTIVE

Genetic high-risk assessment combines hereditary breast, ovarian and pancreatic cancer into one syndrome. However, there is a lack of data for comparing the germline mutational spectrum of the cancer predisposing genes between these three cancers.

METHODS

Patients who met the criteria of the hereditary breast, ovarian and pancreatic cancer were enrolled and received multi-gene sequencing.

RESULTS

We enrolled 730 probands: 418 developed breast cancer, 185 had ovarian cancer, and 145 had pancreatic cancer. Out of the 18 patients who had two types of cancer, 16 had breast and ovarian cancer and 2 had breast and pancreatic cancer. A total of 167 (22.9%) patients had 170 mutations. Mutation frequency in breast, ovarian and pancreatic cancer was 22.3%, 33.5% and 17.2%, respectively. The mutation rate was significantly higher in patients with double cancers than those with a single cancer (p<0.001). BRCA1 and BRCA2 were the most dominant genes associated with hereditary breast and ovarian cancer, whereas ATM was the most prevalent gene related to hereditary pancreatic cancer. Genes of hereditary colon cancer such as lynch syndrome were presented in a part of patients with pancreatic or ovarian cancer but seldom in those with breast cancer. Families with a history of both ovarian and breast cancer were associated with a higher mutation rate than those with other histories.

CONCLUSION

The mutation spectrum varies across the three cancer types and family histories. Our analysis provides guidance for physicians, counsellors, and counselees on the offer and uptake of genetic counseling.

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.

Landscape of germline BRCA1/BRCA2 variants in breast and ovarian cancer in Peru

Background

There is an increasing amount of data from Latin America on the characterization of BRCA variants; however, there is limited information from Peru. We conducted a retrospective study to describe germline pathogenic/likely pathogenic(P/LP) variants and variants of uncertain/unknown significance (VUS) in the BRCA1 and BRCA2 genes in Peru, in patients with breast and ovarian cancer, candidates for treatment with poly (adenosine diphosphate-ribose) polymerase (PARP) inhibitors.

Methods

The patients were evaluated during the period 2019-2021. Genomic DNA was isolated from peripheral blood samples and targeted sequencing was performed using the Ampliseq BRCA panel. Genetic variant interpretation was carried out in accordance with the recommendations of the American College of Medical Genetics and ClinVar. During this period, 525 patients (143 with breast cancer and 382 with ovarian cancer) were studied.

Results

We found that 14.7% (21/143) of breast cancer patients and 20.7% (79/382) of ovarian cancer patients were carriers of P/LP variants in BRCA1/2. The most frequent pathogenic variants detected in BRCA1 were c.2105dupT (BIC: 2224insT, n=12, 18.75%), c.68_69delAG (BIC: 185delAG, n=6, 9.38%), c.140G>T and c.815_824dupAGCCATGTGG (n=5, 7.81%), while in BRCA2 were c.8023A>G (n=6, 16.67%), c.6024dupG (BIC: 6252insG, n=4, 11.11%), and c.9235delG (BIC: 9463delG, n=3, 8.33%). Regarding VUS, we found that 6.99% (10/143) of breast cancer patients and 7.33% (28/382) of ovarian cancer patients were carriers of a VUS in BRCA1/2. For BRCA1, the most frequent VUS was c.93C>G (n=2), and for BRCA2, c.5465A>T (n=4), c.3101T>C (n=3), c.205C>A and c.437T>C (n=2).

Conclusion

We found a frequency of 14.7% germline mutations in breast cancer patients and 20.7% in ovarian cancer patients. The most recurrent mutations were BRCA1 c.2105dupT and BRCA2 c.8023A>G. We found that BRCA2 c.8023A>G, c.6024dupG, and c.9235delG were not previously reported in Peruvian patients. BRCA1 c.2344dupA is a novel mutation that has not been previously reported in any database. The frequency of VUS in our cohort was 7.2%.

Differential involvement of germline pathogenic variants in breast cancer genes between DCIS and low-grade invasive cancers

PURPOSE

To investigate frequency of germline pathogenic variants (PVs) in women with ductal carcinoma in situ (DCIS) and grade 1 invasive breast cancer (G1BC).

METHODS

We undertook BRCA1/2 analysis in 311 women with DCIS and 392 with G1BC and extended panel testing (non-BRCA1/2) in 176/311 with DCIS and 156/392 with G1BC. We investigated PV detection by age at diagnosis, Manchester Score (MS), DCIS grade and receptor status.

RESULTS

30/311 (9.6%) with DCIS and 16/392 with G1BC (4.1%) had a BRCA1/2 PV (p=0.003), and 24/176-(13.6%) and 7/156-(4.5%), respectively, a non-BRCA1/2 PV (p=0.004). Increasing MS was associated with increased likelihood of BRCA1/2 PV in both DCIS and G1BC, although the 10% threshold was not predictive for G1GB. 13/32 (40.6%) DCIS and 0/17 with G1BC <40 years had a non-BRCA1/2 PV (p<0.001). 0/16 DCIS G1 had a PV. For G2 and G3 DCIS, PV rates were 10/98 (BRCA1/2) and 9/90 (non-BRCA1/2), and 8/47 (BRCA1/2) and 8/45 (non-BRCA1/2), respectively. 6/9 BRCA1 and 3/26 BRCA2-associated DCIS were oestrogen receptor negative-(p=0.003). G1BC population testing showed no increased PV rate (OR=1.16, 95% CI 0.28 to 4.80).

CONCLUSION

DCIS is more likely to be associated with both BRCA1/2 and non-BRCA1/2 PVs than G1BC. Extended panel testing ought to be offered in young-onset DCIS where PV detection rates are highest.

Risk of metastasis in BRCA2 carriers diagnosed with triple-negative breast cancer

BACKGROUND

Triple-negative breast cancer (TNBC) is the neoplasia most associated with BRCA1 germline pathogenic variants (PV) and is more likely to develop metastases than the other breast cancer (BC) subtypes, mainly in the lungs and the central nervous system (CNS). Recently, BRCA2 carriers were shown to have a higher risk for developing CNS metastases. However, the patterns of recurrence and metastases of BRCA2 carriers with TNBC are unknown.

METHODS

TNBC patient data attending the A.C. Camargo Cancer Center, from 1998 through 2020, were verified either by medical records or by BRCA1/2 genetic testing carried out. Multivariable logistic regression models were fit to the data to assess the independent factors for bone and CNS metastases. Adjustment was done using all independent variables with p < 0.2 in the univariable Cox model to describe the relationship between the independent variables until time of death.

RESULTS

A total of 388 TNBC patients were evaluated. We identified PV in BRCA1/2 genes in 21% (82/388), being 17.7% (69/388) in BRCA1 and only 3.3% (13/388) in BRCA2. A total of 120 patients (31%) developed distant metastases. Bone or CNS metastases were observed in 40% and 60% of BRCA2 PV carriers (p = 0.155), respectively. The BRCA2 carriers tended to have a higher likelihood of developing bone metastases (OR, 4.06; 95% CI, 0.82-20.01; p = 0.085), when compared to BRCA1 carriers (OR, 0.6; 95% CI, 0.12-2.87; p = 0.528). BRCA2 carriers had an OR of 1.75 (95% CI, 0.33-9.14; p = 0.503) for CNS metastasis development, while BRCA1 carriers had an OR of 0.72 (95% CI, 0.23-2.23; p = 0.574).

CONCLUSIONS

Patients with TNBC and PV in the BRCA2 gene had higher frequencies of secondary bone involvement and CNS in the course of the disease. However, the BRCA2 PV did not represent an independent outcome predictor of metastases and overall survival. Efforts to increase the number of BRCA2 carriers among TNBC patients are crucial for determining their risk of developing bone and CNS metastases compared to BRCA2 noncarriers.

Metaplastic breast cancer: an all-round multidisciplinary consensus

Metaplastic breast cancer (MpBC) is a rare and aggressive histologic subtype of breast cancer (BC) characterized by the presence of at least two cellular types, commonly epithelial and mesenchymal components. Despite growing evidence that MpBC is a unique entity, it has long been treated as a variant of nonspecial type (NST) BC. MpBC typically shows the phenotype of triple-negative breast cancer (TNBC), but compared to NST-TNBC, it is a relatively chemorefractory tumor associated with worse outcomes. Therefore, there is an urgent need to develop management guidelines specifically for MpBC to improve the prognosis of patients with early MpBC. This expert consensus aims to guide diagnosis and standardize clinical management of early MpBC among treating physicians. We provide guidance on the challenging radiological and pathological diagnosis of MpBC. Evidence on the involvement of genetic predisposition in the development of MpBC is also explored. We emphasize the importance of a multidisciplinary approach for the treatment of patients with early MpBC. The optimal surgery and radiotherapy approach is presented, as well as the opportunity offered by novel therapeutic approaches to increase treatment response in this chemoresistant subtype. Appropriate management of patients with MpBC is critical to reduce the high risk of local and distant recurrence that characterizes this disease.

An overview of the research progress of BRCA gene mutations in breast cancer

The breast cancer susceptibility gene (BRCA) is an important tumor suppressor gene, including BRCA1 and BRCA2, a biomarker that assesses the risk of breast cancer and influences a patient's individualized treatment options. BRCA1/2 mutation (BRCAm) increases the risk of breast cancer. However, breast-conserving surgery is still an option for BRCAm, and prophylactic mastectomy and nipple-sparing mastectomy may also reduce the risk of breast cancer. BRCAm is sensitive to Poly (ADP-ribose) polymerase inhibitor (PARPi) therapy due to specific types of DNA repair defects, and its combination with other DNA damage pathway inhibitors and endocrine therapy and immunotherapy are also used for the treatment of BRCAm breast cancer. The current treatment and research progress of BRCA1/2 mutant breast cancer in this review provides a basis for the individualized treatment of patients with this type of breast cancer.

Progress and prospects in research and clinical practice of hormone receptor-positive, HER-2-negative breast cancer with BRCA1/2 mutations

Breast cancer (BC) is a heterogeneous disease that is the most common cancer in women worldwide. However, precise subtyping and corresponding treatments have improved patient outcomes. Hormone receptor (HR)-positive, human epidermal growth factor receptor type 2 (HER2)-negative (HR+/HER2-) BC with BRCA1 and/or BRCA2 mutations (BRCA1/2m) is a unique BC subset with dual drivers: homologous recombination deficiency and hormone receptor signaling. Wild-type BRCA1/2 suppresses estrogen receptor-mediated signaling. Loss-of-function mutations in BRCA1/2 release estrogen receptor suppression, leading to reduced sensitivity to endocrine therapy. Poly (ADP-ribose) polymerase (PARP) inhibitors (PARPis) exert antitumor effects against this subtype and can be used in combination with endocrine therapy. Although PARPis have been evaluated in metastatic triple-negative breast cancer, their efficacy against HR+/HER2- BC has not been clearly established. The present review summarizes recent advances and prospects in the progress of the HR+/HER2-/BRCA1/2m subgroup. As such, this article provides theoretical guidance for future research and promotes the use of PARPis for the treatment of HR+/HER2-/BRCA1/2m BC.

Associations of height, body mass index, and weight gain with breast cancer risk in carriers of a pathogenic variant in BRCA1 or BRCA2: the BRCA1 and BRCA2 Cohort Consortium

INTRODUCTION

Height, body mass index (BMI), and weight gain are associated with breast cancer risk in the general population. It is unclear whether these associations also exist for carriers of pathogenic variants in the BRCA1 or BRCA2 genes.

PATIENTS AND METHODS

An international pooled cohort of 8091 BRCA1/2 variant carriers was used for retrospective and prospective analyses separately for premenopausal and postmenopausal women. Cox regression was used to estimate breast cancer risk associations with height, BMI, and weight change.

RESULTS

In the retrospective analysis, taller height was associated with risk of premenopausal breast cancer for BRCA2 variant carriers (HR 1.20 per 10 cm increase, 95% CI 1.04-1.38). Higher young-adult BMI was associated with lower premenopausal breast cancer risk for both BRCA1 (HR 0.75 per 5 kg/m2, 95% CI 0.66-0.84) and BRCA2 (HR 0.76, 95% CI 0.65-0.89) variant carriers in the retrospective analysis, with consistent, though not statistically significant, findings from the prospective analysis. In the prospective analysis, higher BMI and adult weight gain were associated with higher postmenopausal breast cancer risk for BRCA1 carriers (HR 1.20 per 5 kg/m2, 95% CI 1.02-1.42; and HR 1.10 per 5 kg weight gain, 95% CI 1.01-1.19, respectively).

CONCLUSION

Anthropometric measures are associated with breast cancer risk for BRCA1 and BRCA2 variant carriers, with relative risk estimates that are generally consistent with those for women from the general population.

BRCA germline mutations in multiethnic gynecologic patients: A 10-year retrospective analysis from a single cancer institute

Histologic and genetic mutation information from racially and ethnically diverse populations is warranted to better inform future cancer predisposition and promote health equity. A single institutional, retrospective capture of patients with gynecologic conditions and genetic susceptibilities to malignant neoplasms of the breast or ovaries was performed. This was achieved with manual curation of the electronic medical record (EMR) from 2010-2020 with the use of ICD-10 code searches. Among 8983 consecutive women identified with gynecologic conditions, 184 were diagnosed with pathogenic/likely pathogenic (P/LP) germline BRCA (gBRCA) mutations. Median age was 54 (22-90). Mutations included insertion/deletion (majority frameshift, 57.4%), substitution (32.4%), large structural rearrangement (5.4%), and alteration in splice site/intronic sequence (4.7%). A total of 48% were non-Hispanic White, 32% Hispanic or Latino, 13% Asian, 2% Black, and 5% Other. The most common pathology was high grade serous carcinoma (HGSC, 63%), followed by unclassified/high grade carcinoma (13%). Additional multigene panels led to the detection of 23 additional BRCA-positive patients with germline co-mutations and/or variants of uncertain significance in genes functionally involved in DNA repair mechanisms. Hispanic or Latino and Asian individuals comprised 45% of patients with concomitant gynecologic condition and gBRCA positivity in our cohort, confirming that germline mutations are represented across racial and ethnic groups. Insertion/deletion mutations, the majority of which led to a frameshift change, occurred in approximately half of our patient cohort, which may have prognostic implication for therapy resistance. Prospective studies are needed to unravel the significance of germline co-mutations in gynecologic patients.

Efficacy of front-line treatment for hormone receptor-positive HER2-negative metastatic breast cancer with germline BRCA1/2 mutation

BACKGROUND

Efficacy of endocrine therapy in HR+/HER2- metastatic breast cancer could differ depending on the presence of BRCA1/2 germline mutation.

METHODS

The ESME metastatic breast cancer platform (NCT03275311) is a French real world database. Multivariable models including a time-varying approach and landmark analyses assessed the association between time-dependent gBRCA status (categorised as gBRCAm, gBRCAwt (wild type), and untested), overall survival (OS), and first-line progression-free survival (PFS1).

RESULTS

A total of 170 patients were gBRCAm carriers, 676 gBRCAwt, and 12,930 were untested at baseline. In the multivariable analysis, gBRCAm carriers overall had a lower OS compared to gBRCAwt (adjusted HR [95% CI] 1.26 [1.03-1.55]). gBRCAm patients treated with front-line endocrine therapy had lower adjusted OS (adjusted HR [95% CI] = 1.54 [1.03-2.32]) and PFS1 (adjusted HR [95% CI] 1.58 [1.17-2.12]) compared to gBRCAwt patients. However, for patients who received frontline chemotherapy, neither OS nor PFS1 differed between gBRCAm carriers and the other groups (HR versus gBRCAwt for OS: 1.12 [0.88-1.41], p = 0.350; PFS1: 1.09 [0.90-1.31], p = 0.379).

CONCLUSION

In this large cohort of HR+/HER2- MBC patients treated in a pre-CDK4/6 inhibitors era, gBRCAm status was associated with a lower OS and lower PFS following first-line endocrine therapy, but not following first-line chemotherapy.

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

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

Hereditary Breast Cancer in Romania-Molecular Particularities and Genetic Counseling Challenges in an Eastern European Country

In Romania, breast cancer (BC) is the most common malignancy in women. However, there is limited data on the prevalence of predisposing germline mutations in the population in the era of precision medicine, where molecular testing has become an indispensable tool in cancer diagnosis, prognosis, and therapeutics. Therefore, we conducted a retrospective study to determine the prevalence, mutational spectrum, and histopathological prediction factors for hereditary breast cancer (HBC) in Romania. A cohort of 411 women diagnosed with BC selected upon NCCN v.1.2020 guidelines underwent an 84-gene NGS-based panel testing for breast cancer risk assessment during 2018-2022 in the Department of Oncogenetics of the Oncological Institute of Cluj-Napoca, Romania. A total of 135 (33%) patients presented pathogenic mutations in 19 genes. The prevalence of genetic variants was determined, and demographic and clinicopathological characteristics were analyzed. We observed differences among BRCA and non-BRCA carriers regarding family history of cancer, age of onset, and histopathological subtypes. Triple-negative (TN) tumors were more often BRCA1 positive, unlike BRCA2 positive tumors, which were more often the Luminal B subtype. The most frequent non-BRCA mutations were found in CHEK2, ATM, and PALB2, and several recurrent variants were identified for each gene. Unlike other European countries, germline testing for HBC is still limited due to the high costs and is not covered by the National Health System (NSH), thus leading to significant discrepancies related to the screening and prophylaxis of cancer.

Targeted Therapies and the Evolving Standard of Care for Triple-Negative and Germline BRCA1/2-Mutated Breast Cancers in the High-Risk, Early-Stage Setting

PURPOSE

Immune checkpoint inhibitors (ICIs) and poly (ADP-ribose) polymerase (PARP) inhibitors have transformed the treatment landscape of metastatic triple-negative breast cancer (TNBC). Trial results have demonstrated the clinical benefit of these targeted agents in the advanced TNBC setting and have led to their evaluation in the treatment of high-risk, early-stage TNBC and BRCA-mutated breast cancer. We provide a summary of the results that have led to the establishment of the ICI pembrolizumab and the PARP inhibitor olaparib as new standards of care.

METHODS

Using PubMed, we searched for original articles published in English between 2017 and 2022. Search terms included triple-negative breast cancer, adjuvant, neoadjuvant, immunotherapy, and PARP inhibitors.

RESULTS

Two targeted therapies have been approved by the US Food and Drug Administration for the treatment of TNBC and BRCA-mutated breast cancers in the high-risk, early-stage setting on the basis of clinical trial results demonstrating improved clinical outcomes. For high-risk, early-stage TNBC, pembrolizumab was approved as neoadjuvant therapy in combination with chemotherapy and as a single agent for continued treatment after surgery; this approval was based on results of the KEYNOTE-522 trial. Olaparib was approved for the adjuvant treatment of patients with high-risk, early-stage human epidermal growth factor receptor type 2 (HER2)-negative breast cancer with germline BRCA1/2 mutations who have been previously treated with neoadjuvant or adjuvant chemotherapy on the basis of the OlympiA trial results.

CONCLUSION

Clinical trial results demonstrate the pronounced clinical benefits of pembrolizumab combined with chemotherapy for high-risk, early-stage TNBC and adjuvant olaparib for high-risk, early-stage HER2-negative BRCA1/2-mutated breast cancer.

Molecular characteristics of breast tumors in patients screened for germline predisposition from a population-based observational study

BACKGROUND

Pathogenic germline variants (PGVs) in certain genes are linked to higher lifetime risk of developing breast cancer and can influence preventive surgery decisions and therapy choices. Public health programs offer genetic screening based on criteria designed to assess personal risk and identify individuals more likely to carry PGVs, dividing patients into screened and non-screened groups. How tumor biology and clinicopathological characteristics differ between these groups is understudied and could guide refinement of screening criteria.

METHODS

Six thousand six hundred sixty breast cancer patients diagnosed in South Sweden during 2010-2018 were included with available clinicopathological and RNA sequencing data, 900 (13.5%) of which had genes screened for PGVs through routine clinical screening programs. We compared characteristics of screened patients and tumors to non-screened patients, as well as between screened patients with (n = 124) and without (n = 776) PGVs.

RESULTS

Broadly, breast tumors in screened patients showed features of a more aggressive disease. However, few differences related to tumor biology or patient outcome remained significant after stratification by clinical subgroups or PAM50 subtypes. Triple-negative breast cancer (TNBC), the subgroup most enriched for PGVs, showed the most differences between screening subpopulations (e.g., higher tumor proliferation in screened cases). Significant differences in PGV prevalence were found between clinical subgroups/molecular subtypes, e.g., TNBC cases were enriched for BRCA1 PGVs. In general, clinicopathological differences between screened and non-screened patients mimicked those between patients with and without PGVs, e.g., younger age at diagnosis for positive cases. However, differences in tumor biology/microenvironment such as immune cell composition were additionally seen within PGV carriers/non-carriers in ER + /HER2 - cases, but not between screening subpopulations in this subgroup.

CONCLUSIONS

Characterization of molecular tumor features in patients clinically screened and not screened for PGVs represents a relevant read-out of guideline criteria. The general lack of molecular differences between screened/non-screened patients after stratification by relevant breast cancer subsets questions the ability to improve the identification of screening candidates based on currently used patient and tumor characteristics, pointing us towards universal screening. Nevertheless, while that is not attained, molecular differences identified between PGV carriers/non-carriers suggest the possibility of further refining patient selection within certain patient subsets using RNA-seq through, e.g., gene signatures.

TRIAL REGISTRATION

The Sweden Cancerome Analysis Network - Breast (SCAN-B) was prospectively registered at ClinicalTrials.gov under the identifier NCT02306096.

Harnessing Epigenetics for Breast Cancer Therapy: The Role of DNA Methylation, Histone Modifications, and MicroRNA

Breast cancer exhibits various epigenetic abnormalities that regulate gene expression and contribute to tumor characteristics. Epigenetic alterations play a significant role in cancer development and progression, and epigenetic-targeting drugs such as DNA methyltransferase inhibitors, histone-modifying enzymes, and mRNA regulators (such as miRNA mimics and antagomiRs) can reverse these alterations. Therefore, these epigenetic-targeting drugs are promising candidates for cancer treatment. However, there is currently no effective epi-drug monotherapy for breast cancer. Combining epigenetic drugs with conventional therapies has yielded positive outcomes and may be a promising strategy for breast cancer therapy. DNA methyltransferase inhibitors, such as azacitidine, and histone deacetylase inhibitors, such as vorinostat, have been used in combination with chemotherapy to treat breast cancer. miRNA regulators, such as miRNA mimics and antagomiRs, can alter the expression of specific genes involved in cancer development. miRNA mimics, such as miR-34, have been used to inhibit tumor growth, while antagomiRs, such as anti-miR-10b, have been used to inhibit metastasis. The development of epi-drugs that target specific epigenetic changes may lead to more effective monotherapy options in the future.

Triple-negative breast cancer: epidemiology, molecular mechanisms, and modern vaccine-based treatment strategies

Long-standing scarcity of efficacious treatments and tumor heterogeneity have contributed to triple-negative breast cancer (TNBC), a subtype with a poor prognosis and aggressive behavior that accounts for 10-15% of all new cases of breast cancer. TNBC is characterized by the absence of progesterone and estrogen receptor expression and lacks gene amplification or overexpression of HER2. Genomic sequencing has detected that the unique mutational profile of both the somatic and germline modifications in TNBC is staggeringly dissimilar from other breast tumor subtypes. The clinical utility of sequencing germline BRCA1/2 genes has been well established in TNBC. Nevertheless, reports regarding the penetrance and risk of other susceptibility genes are relatively scarce. Recurring mutations (e.g., TP53 and PI3KCA mutations) occur together with rare mutations in TNBC, and the shared effects of genomic modifications drive its progression. Given the heterogeneity and complexity of this disease, a clinical understanding of the genomic modifications in TNBC can pave an innovative way toward its therapy. In this review, we summarized the most recent discoveries associated with the underlying biology of developmental signaling pathways in TNBC. We also summarize the recent advancements in genetics and epidemiology and discuss state-of-the-art vaccine-based therapeutic strategies for TNBC that will enable tailored therapeutics.

Genetic Analysis of Multiple Primary Malignant Tumors in Women with Breast and Ovarian Cancer

Familial cancer syndromes, which are commonly caused by germline mutations in oncogenes and tumor suppressor genes, are generally considered to be the cause of primary multiple malignant neoplasias (PMMNs). Using targeted genomic sequencing, we screened for eight germline mutations: BRCA1 185delAG, BRCA1 T300G, BRCA1 2080delA, BRCA1 4153delA, BRCA1 5382insC, BRCA2 6174delT, CHEK2 1100delC, and BLM C1642T, which provoke the majority of cases of hereditary breast and ovary cancer syndrome (HBOC), in genomic (blood) DNA from 60 women with PMMNs, including breast (BC) and/or ovarian cancer(s) (OC). Pathogenic allelic forms were discovered in nine samples: in seven instances, it was BRCA1 5382insC, and in the following two, BRCA1 4153delA and BRCA1 T300G. The age of onset in these patients (46.8 years) was younger than in the general Russian population (61.0) for BC but was not for OC: 58.3 and 59.4, correspondingly. There were invasive breast carcinomas of no special type and invasive serous ovarian carcinomas in all cases. Two or more tumors of HBOC-spectrum were only in five out of nine families of mutation carriers. Nevertheless, every mutation carrier has relatives who have developed malignant tumors.

Chemotherapy-related agranulocytosis as a predictive factor for germline BRCA1 pathogenic variants in breast cancer patients: a retrospective cohort study

BACKGROUND

Carriers of germline pathogenic variants of the BRCA1 gene (gBRCA1) tend to have a higher incidence of haematological toxicity upon exposure to chemotherapy. We hypothesised that the occurrence of agranulocytosis during the first cycle of (neo-)adjuvant chemotherapy (C1) in breast cancer (BC) patients could predict gBRCA1 pathogenic variants.

PATIENTS AND METHODS

The study population included non-metastatic BC patients selected for genetic counselling at Hôpitaux Universitaires de Genève (Jan. 1998 to Dec. 2017) with available mid-cycle blood counts performed during C1. The BOADICEA and Manchester scoring system risk-prediction models were applied. The primary outcome was the predicted likelihood of harbouring gBRCA1 pathogenic variants among patients presenting agranulocytosis during C1.

RESULTS

Three hundred seven BC patients were included: 32 (10.4%) gBRCA1, 27 (8.8%) gBRCA2, and 248 (81.1%) non-heterozygotes. Mean age at diagnosis was 40 years. Compared with non-heterozygotes, gBRCA1 heterozygotes more frequently had grade 3 BC (78.1%; p = 0.014), triple-negative subtype (68.8%; p <0.001), bilateral BC (25%; p = 0.004), and agranulocytosis following the first cycle of (neo-)adjuvant chemotherapy (45.8%; p = 0.002). Agranulocytosis and febrile neutropenia that developed following the first cycle of chemotherapy were independently predictive for gBRCA1 pathogenic variants (odds ratio: 6.1; p = 0.002). The sensitivity, specificity, positive predictive value, and negative predictive value for agranulocytosis predicting gBRCA1 were 45.8% (25.6-67.2%), 82.8% (77.5-87.3%), 22.9% (6.1-37.3%), and 93.4% (88.9-96.4%), respectively. Agranulocytosis substantially improved the positive predictive value of the risk-prediction models used for gBRCA1 evaluation.

CONCLUSION

Agranulocytosis following the first cycle of (neo-)adjuvant chemotherapy is an independent predictive factor for gBRCA1 detection in non-metastatic BC patients.

Breast Cancer Screening in Men

Breast cancer screening has been highly successful in women in reducing mortality through early detection. In comparison, clinical detection of breast cancer remains the norm in men, and delay in diagnosis is reflected by a persistent survival disparity compared to women despite advances in modern therapy. Male breast cancer presents an interesting dilemma. While mammography is highly sensitive and specific for male breast cancer, routine screening is not justified by the overall low disease incidence. Yet there has been interest in leveraging mammography in targeted screening of men with identifiable risk factors to allow early detection, and early data may support this approach. The purpose of this article is to explore the potential utility of targeted breast cancer screening in men by examining unique clinical and biologic characteristics of male breast cancers that may lend themselves to mammographic detection. We will also discuss available evidence in screening outcomes in men and summarize recent updates in risk management recommendations in Society guidelines.

How Does Dietary Intake Relate to Dispositional Optimism and Health-Related Quality of Life in Germline BRCA1/2 Mutation Carriers?

Background: The Mediterranean diet (MD) is an anti-inflammatory diet linked to improved health-related quality of life (HRQoL). Germline (g)BRCA1/2 mutation carriers have an increased risk of developing breast cancer and are often exposed to severe cancer treatments, thus the improvement of HRQoL is important. Little is known about the associations between dietary intake and HRQoL in this population. Methods: We included 312 gBRCA1/2 mutation carriers from an ongoing prospective randomized controlled lifestyle intervention trial. Baseline data from the EPIC food frequency questionnaire was used to calculate the dietary inflammatory index (DII), and adherence to MD was captured by the 14-item PREDIMED questionnaire. HRQoL was measured by the EORTC QLQ-C30 and LOT-R questionnaires. The presence of metabolic syndrome (MetS) was determined using anthropometric measurements, blood samples and vital parameters. Linear and logistic regression models were performed to assess the possible impact of diet and metabolic syndrome on HRQoL. Results: Women with a prior history of cancer (59.6%) reported lower DIIs than women without it (p = 0.011). A greater adherence to MD was associated with lower DII scores (p < 0.001) and reduced odds for metabolic syndrome (MetS) (p = 0.024). Women with a more optimistic outlook on life reported greater adherence to MD (p < 0.001), whereas a more pessimistic outlook on life increased the odds for MetS (OR = 1.15; p = 0.023). Conclusions: This is the first study in gBRCA1/2 mutation carriers that has linked MD, DII, and MetS to HRQoL. The long-term clinical implications of these findings are yet to be determined.

Imaging Recommendations for Diagnosis, Staging, and Management of Hereditary Malignancies

Hereditary cancer syndromes, characterized by genetically distinct neoplasms developing in specific organs in more than one family members, predispose an individual to early onset of distinct site-specific tumors. Early age of onset, multiorgan involvement, multiple and bilateral tumors, advanced disease at presentation, and aggressive tumor histology are few characteristic features of hereditary cancer syndromes. A multidisciplinary approach to hereditary cancers has led to a paradigm shift in the field of preventive oncology and precision medicine. Imaging plays a pivotal role in the screening, testing, and follow-up of individuals and their first- and second-degree relatives with hereditary cancers. In fact, a radiologist is often the first to apprise the clinician about the possibility of an underlying hereditary cancer syndrome based on pathognomonic imaging findings. This article focuses on the imaging spectrum of few common hereditary cancer syndromes with specific mention of the imaging features of associated common and uncommon tumors in each syndrome. The screening and surveillance recommendations for each condition with specific management approaches, in contrast to sporadic cases, have also been described.

Survival outcomes of metastatic breast cancer patients by germline BRCA1/2 status in a large multicenter real-world database

The outcomes and best treatment strategies for germline BRCA1/2 mutation (gBRCAm) carriers with metastatic breast cancer (MBC) remain uncertain. We compared the overall survival and the first line progression free survival (PFS1) of patients with a gBRCAm identified at initiation of first-line treatment with those of BRCA wild-type (WT) and not-tested (NT) individuals in the ESME real-world database of MBC patients between 2008 and 2016 (NCT03275311). Among the 20 624 eligible patients, 325 had a gBRCAm, 1138 were WT and 19 161 NT. Compared with WT, gBRCAm carriers were younger, and had more aggressive diseases. At a median follow-up of 50.5 months, median OS was 30.6 (95%CI: 21.9-34.3), 35.8 (95%CI: 32.2-37.8) and 39.3 months (95% CI: 38.3-40.3) in the gBRCAm, WT and NT subgroups, respectively. Median PFS1 was 7.9 (95%CI: 6.6-9.3), 7.8 (95%CI: 7.3-8.5) and 9.7 months (95%CI, 9.5-10.0). In the multivariable analysis conducted in the whole cohort, gBRCAm status had however no independent prognostic impact on OS and PFS1. Though, in the triple-negative subgroup, gBRCAm patients had better OS and PFS1 (HR vs WT = 0.76; 95%CI: 0.60-0.97; P = .027 and 0.69; 95% CI: 0.55-0.86; P = .001, respectively). In contrast, in patients with HR+/HER2 negative cancers, PFS1 appeared significantly and OS non significantly lower for gBRCAm carriers (PFS1: HR vs WT = 1.23; 95%CI: 1.03-1.46; P = .024; OS:HR = 1.22, 95% CI: 0.97-1.52, P = .089). In conclusion, gBRCA1/2 status appears to have divergent survival effects in MBC according to IHC subtype.

Hereditary cancer syndromes

Hereditary cancer syndromes (HCSs) are arguably the most frequent category of Mendelian genetic diseases, as at least 2% of presumably healthy subjects carry highly-penetrant tumor-predisposing pathogenic variants (PVs). Hereditary breast-ovarian cancer and Lynch syndrome make the highest contribution to cancer morbidity; in addition, there are several dozen less frequent types of familial tumors. The development of the majority albeit not all hereditary malignancies involves two-hit mechanism, i.e. the somatic inactivation of the remaining copy of the affected gene. Earlier studies on cancer families suggested nearly fatal penetrance for the majority of HCS genes; however, population-based investigations and especially large-scale next-generation sequencing data sets demonstrate that the presence of some highly-penetrant PVs is often compatible with healthy status. Hereditary cancer research initially focused mainly on cancer detection and prevention. Recent studies identified multiple HCS-specific drug vulnerabilities, which translated into the development of highly efficient therapeutic options.

Efficacy of PARP Inhibitor, Platinum, and Immunotherapy in BRCA-Mutated HER2-Negative Breast Cancer Patients: A Systematic Review and Network Meta-Analysis

The optimal treatment regimen for breast cancer patients with gBRCA mutations remains controversial given the availability of numerous options, such as platinum-based agents, polymerase inhibitors (PARPis), and other agents. We included phase II or III RCTs and estimated the HR with 95% CI for OS, PFS, and DFS, in addition to the OR with 95% CI for ORR and pCR. We determined the treatment arm rankings by P-scores. Furthermore, we carried out a subgroup analysis in TNBC and HR-positive patients. We conducted this network meta-analysis using R 4.2.0 and a random-effects model. A total of 22 RCTs were eligible, involving 4253 patients. In the pairwise comparisons, PARPi + Platinum + Chemo was better than PARPi + Chemo for OS (in whole study group and in both subgroups) as well as PFS. The ranking tests demonstrated that PARPi + Platinum + Chemo ranked first in PFS, DFS, and ORR. Platinum + Chemo showed higher OS than PARPi + Chemo. The ranking tests for PFS, DFS, and pCR indicated that, except for the best treatment (PARPi + Platinum + Chemo) containing PARPi, the second and third treatments were platinum monotherapy or platinum-based chemotherapy. In conclusion, PARPi + Platinum + Chemo might be the best regime for gBRCA-mutated BC. Platinum drugs showed more favorable efficacy than PARPi in both combination and monotherapy.