Hereditary breast and ovarian cancer (HBOC): review of its molecular characteristics, screening, treatment, and prognosis

Low testing rates and high BRCA prevalence: Poly (ADP-ribose) polymerase inhibitor use in Middle East BRCA/homologous recombination deficiency-positive cancer patients

BACKGROUND

Poly (ADP-ribose) polymerase inhibitors (PARPis) are approved as first-line therapies for breast cancer gene (BRCA)-positive, human epidermal growth factor receptor 2-negative locally advanced or metastatic breast cancer. They are also effective for new and recurrent ovarian cancers that are BRCA- or homologous recombination deficiency (HRD)-positive. However, data on these mutations and PARPi use in the Middle East are limited.

AIM

To assess BRCA/HRD prevalence and PARPi use in patients in the Middle East with breast/ovarian cancer.

METHODS

This was a single-center retrospective study of 57 of 472 breast cancer patients tested for BRCA mutations, and 25 of 65 ovarian cancer patients tested for HRD. These adult patients participated in at least four visits to the oncology service at our center between August 2021 and May 2023. Data were summarized using descriptive statistics and compared using counts and percentages. Response to treatment was assessed using Response Evaluation Criteria in Solid Tumors criteria.

RESULTS

Among the 472 breast cancer patients, 12.1% underwent BRCA testing, and 38.5% of 65 ovarian cancer patients received HRD testing. Pathogenic mutations were found in 25.6% of the tested patients: 26.3% breast cancers had germline BRCA (gBRCA) mutations and 24.0% ovarian cancers showed HRD. Notably, 40.0% of gBRCA-positive breast cancers and 66.0% of HRD-positive ovarian cancers were Middle Eastern and Asian patients, respectively. PARPi treatment was used in 5 (33.3%) gBRCA-positive breast cancer patients as first-line therapy (n = 1; 7-months progression-free), for maintenance (n = 2; > 15-months progression-free), or at later stages due to compliance issues (n = 2). Four patients (66.6%) with HRD-positive ovarian cancer received PARPi and all remained progression-free.

CONCLUSION

Lower testing rates but higher BRCA mutations in breast cancer were found. Ethnicity reflected United Arab Emirates demographics, with breast cancer in Middle Eastern and ovarian cancer in Asian patients.

Peripheral immunophenotyping reveals lymphocyte stimulation in healthy women living with hereditary breast and ovarian cancer syndrome

Germline pathogenic variants in BRCA1 and BRCA2 (gpath(BRCA1/2)) represent genetic susceptibility for hereditary breast and ovarian cancer syndrome. Tumor-immune interactions are key contributors to breast cancer pathogenesis. Although earlier studies confirmed pro-tumorigenic immunological alterations in breast cancer patients, data are lacking in healthy carriers of gpath(BRCA1/2). Peripheral blood mononuclear cells of 66 women with or without germline predisposition or breast cancer were studied with a mass cytometry panel that identified 4 immune subpopulations of altered frequencies between healthy controls and healthy gpath(BRCA1) carriers, while no difference was observed in healthy gpath(BRCA2) carriers compared to controls. Moreover, 3 (one IgD-CD27+CD95+ B cell subpopulation and two CD45RA-CCR7+CD38+ CD4+ T cell subpopulations) out of these 4 subpopulations were also elevated in triple-negative breast cancer patients compared to controls. Our results reveal an activated peripheral immune phenotype in healthy carriers of gpath(BRCA1) that needs to be further elucidated to be leveraged in risk-reducing strategies.

Methylation marks in blood DNA reveal breast cancer risk in patients fulfilling hereditary disease criteria

Less than 15-20% of patients who meet the criteria for hereditary breast and ovarian cancer (HBOC) carry pathogenic coding genetic mutations, implying that other molecular mechanisms may contribute to the increased risk of this condition. DNA methylation in peripheral blood has been suggested as a potential epigenetic marker for the risk of breast cancer (BC). We aimed to discover methylation marks in peripheral blood associated with BC in 231 pre-treatment BC patients meeting HBOC criteria, testing negative for coding pathogenic variants, and 156 healthy controls, through methylation analysis by targeted bisulfite sequencing on 18 tumor suppressor gene promoters (330 CpG sites). We found i) hypermethylation in EPCAM (17 CpG sites; p = 0.017) and RAD51C (27 CpG sites; p = 0.048); ii) hypermethylation in 36 CpG-specific sites (FDR q < 0.05) in the BC patients; iii) four specific CpG sites were associated with a higher risk of BC (FDR q < 0.01, Bonferroni p < 0.001): cg89786999-FANCI (OR = 1.65; 95% CI:1.2-2.2), cg23652916-PALB2 (OR = 2.83; 95% CI:1.7-4.7), cg47630224-MSH2 (OR = 4.17; 95% CI:2.1-8.5), and cg47596828-EPCAM (OR = 1.84; 95% CI:1.5-2.3). Validation of cg47630224-MSH2 methylation in one Australian cohort showed an association with 3-fold increased BC risk (AUC: 0.929; 95% CI: 0.904-0.955). Our findings suggest that four DNA methylation CpG sites may be associated with a higher risk of BC, potentially serving as biomarkers in patients without detectable coding mutations.

Prevention, diagnosis and clinical management of hereditary breast cancer beyond BRCA1/2 genes

The detection of germline pathogenic variants (gPVs) in BRCA1/2 and other breast cancer (BC) genes is rising exponentially thanks to the advent of multi-gene panel testing. This promising technology, coupled with the availability of specific therapies for BC BRCA-related, has increased the number of patients eligible for genetic testing. Implementing multi-gene panel testing for hereditary BC screening holds promise to maximise benefits for patients at hereditary risk of BC. These benefits range from prevention programs to antineoplastic-targeted therapies. However, the clinical management of these patients is complex and requires guidelines based on recent evidence. Furthermore, applying multi-gene panel testing into clinical practice increases the detection of variants of uncertain significance (VUSs). This augments the complexity of patients' clinical management, becoming an unmet need for medical oncologists. This review aims to collect updated evidence on the most common BC-related genes besides BRCA1/2, from their biological role in BC development to their potential impact in tailoring prevention and treatment strategies.

Cancer risks among first-degree relatives of women with a genetic predisposition to breast cancer

BACKGROUND

Associations between germline alterations in women and cancer risks among their relatives are largely unknown.

METHODS

We identified women from 2 Swedish cohorts Karolinska Mammography Project for Risk Prediction of Breast Cancer (KARMA) and prevalent KARMA (pKARMA), including 28 362 women with genotyping data and 13 226 with sequencing data. Using Swedish Multi-Generation Register, we linked these women to 133 389 first-degree relatives. Associations between protein-truncating variants in 8 risk genes and breast cancer polygenic risk score in index women and cancer risks among their relatives were modeled via Cox regression.

RESULTS

Female relatives of index women who were protein-truncating variant carriers in any of the 8 risk genes had an increased breast cancer risk compared with those of noncarriers (hazard ratio [HR] = 1.85, 95% confidence interval [CI] = 1.52 to 2.27), with the strongest association found for protein-truncating variants in BRCA1 and 2. These relatives had a statistically higher risk of early onset than late-onset breast cancer (P = .001). Elevated breast cancer risk was also observed in female relatives of index women with higher polygenic risk score (HR per SD = 1.28, 95% CI = 1.23 to 1.32). The estimated lifetime risk was 22.3% for female relatives of protein-truncating variant carriers and 14.4% for those related to women in the top polygenic risk score quartile. Moreover, relatives of index women with protein-truncating variant presence (HR = 1.30, 95% CI = 1.06 to 1.59) or higher polygenic risk score (HR per SD = 1.04, 95% CI = 1.01 to 1.07) were also at higher risk of nonbreast hereditary breast and ovary cancer syndrome-related cancers.

CONCLUSIONS

Protein-truncating variants of risk genes and higher polygenic risk score in index women are associated with an increased risk of breast and other hereditary breast and ovary syndrome-related cancers among relatives.

BRCA1 Intragenic Duplication Combined with a Likely Pathogenic TP53 Variant in a Patient with Triple-Negative Breast Cancer: Clinical Risk and Management

For patients with hereditary breast and ovarian cancer, the probability of carrying two pathogenic variants (PVs) in dominant cancer-predisposing genes is rare. Using targeted next-generation sequencing (NGS), we investigated a 49-year-old Caucasian woman who developed a highly aggressive breast tumor. Our analyses identified an intragenic germline heterozygous duplication in BRCA1 with an additional likely PV in the TP53 gene. The BRCA1 variant was confirmed by multiplex ligation probe amplification (MLPA), and genomic breakpoints were characterized at the nucleotide level (c.135-2578_442-1104dup). mRNA extracted from lymphocytes was amplified by RT-PCR and then Sanger sequenced, revealing a tandem duplication r.135_441dup; p.(Gln148Ilefs*20). This duplication results in the synthesis of a truncated and, most likely, nonfunctional protein. Following functional studies, the TP53 exon 5 c.472C > T; p.(Arg158Cys) missense variant was classified as likely pathogenic by the Li-Fraumeni Syndrome (LFS) working group. This type of unexpected association will be increasingly identified in the future, with the switch from targeted BRCA sequencing to hereditary breast and ovarian cancer (HBOC) panel sequencing, raising the question of how these patients should be managed. It is therefore important to record and investigate these rare double-heterozygous genotypes.

Quadruple primary tumors in a lynch syndrome patient surviving more than 26 years with genetic analysis: a case report and literature review

The incidence of multiple primary tumors(MPTs) is on the rise in recent years, but patients having four or more primary tumors is still rare. Lynch syndrome (LS) patients have a high risk of developing MPTs. NGS sequencing could identify the genetic alterations in different tumors to make a definite diagnosis of uncommon cases in clinical practice. Here, we report the case of a 66-year-old female patient who develops four MPTS between the ages of 41 and 66, that is sigmoid colon cancer, acute non-lymphocytic leukemia, urothelial carcinoma and ascending colon cancer. She has survived for more than 26 years since the first discovery of tumor. Targeted sequencing indicates that she has a pathogenic germline mutation in the exon 13 of MSH2, and her 2020 ureteral cancer sample and 2023 colon cancer sample have completely different mutation profiles. To the best of our knowledge, this is the first case of multiple primary tumors with an acute non-lymphocytic leukemia in LS patients.

Cosmic Whirl: Navigating the Comet Trail in DNA: H2AX Phosphorylation and the Enigma of Uncertain Significance Variants

Pathogenic variations in the BRCA2 gene have been detected with the development of next-generation sequencing (NGS)-based hereditary cancer panel testing technology. It also reveals an increasing number of variants of uncertain significance (VUSs). Well-established functional tests are crucial to accurately reclassifying VUSs for effective diagnosis and treatment. We retrospectively analyzed the multi-gene cancer panel results of 922 individuals and performed in silico analysis following ClinVar classification. Then, we selected five breast cancer-diagnosed patients' missense BRCA2 VUSs (T1011R, T1104P/M1168K, R2027K, G2044A, and D2819) for reclassification. The effects of VUSs on BRCA2 function were analyzed using comet and H2AX phosphorylation (γH2AX) assays before and after the treatment of peripheral blood mononuclear cells (PBMCs) of subjects with the double-strand break (DSB) agent doxorubicin (Dox). Before and after Dox-induction, the amount of DNA in the comet tails was similar in VUS carriers; however, notable variations in γH2AX were observed, and according to combined computational and functional analyses, we reclassified T1001R as VUS-intermediate, T1104P/M1168K and D2819V as VUS (+), and R2027K and G2044A as likely benign. These findings highlight the importance of the variability of VUSs in response to DNA damage before and after Dox-induction and suggest that further investigation is needed to understand the underlying mechanisms.

Cascade testing for hereditary cancer in Singapore: how population genomics help guide clinical policy

Hereditary Cancer makes up around 5-10% of all cancers. It is important to diagnose hereditary cancer in a timely fashion, as not only do patients require long-term care from a young age, but their relatives also require management. The main approach to capture at-risk relatives is cascade testing. It involves genetic testing of relatives of the first detected carrier of a pathogenic variant in a family i.e. the proband. The current standard of care for cascade testing is a patient-mediated approach. Probands are then advised to inform and encourage family members to undergo genetic testing. In Singapore, cascade testing is inefficient, around 10-15%, lower than the 30% global average. Here, we describe the cascade testing process and its effort to increase testing in Singapore. Precision Health Research, Singapore (PRECISE), was set up to coordinate Singapore's National Precision Medicine strategy and has awarded five clinical implementation pilots, with one of them seeking to identify strategies for how cascade testing for hereditary cancer can be increased in a safe and cost-efficient manner. Achieving this will be done through addressing barriers such as cost, manpower shortages, exploring a digital channel for contacting at-risk relatives, and getting a deeper insight into why genetic testing gets declined. If successful, it will likely result in care pathways that are a cost-effective public health intervention for identifying individuals at risk. Surveillance and management of those unaffected at-risk individuals, if caught early, will result in improved patient outcomes, and further reduce the healthcare burden for the economy.

Cascade testing in Italian Hereditary Breast Ovarian Cancer families: a missed opportunity for cancer prevention?

Healthy carriers of BRCA1/2 pathogenic variants (PVs) may benefit from risk-reducing measures of proven efficacy. The main approach to identify these individuals is cascade testing, and strategies to support this complex process are under investigation. In Italy, cascade testing has received little attention; therefore, we analyzed the uptake and characteristics of BRCA1/2 cascade testing in families diagnosed with HBOC between 2017 and 2019 at two Italian genetics centers. All blood relatives aged 18 years or older at September 2022 and who could be involved in the first step of cascade testing (i.e., all the living relatives closest to the proband) were included. In addition to first-degree relatives, individuals who were second-, third- or fourth-degree relatives were included if the closest relative(s) was/were deceased. Overall, 213 families were included (103, Genoa; 110, Bologna). Most probands were women affected by breast and/or ovarian cancer (86.4%, Genoa; 84.5%, Bologna), and the branch segregating the PV was known/suspected in 62% of families (62.1%, Genoa; 60.9%, Bologna). Overall, the uptake of cascade testing was 22.8% (25.8%, Genoa; 19.9%, Bologna; OR = 0.59: 95%CI 0.43-0.82). It was strongly associated with female gender (OR = 3.31, 95%CI 2.38-4.59), age ≤ 70 years (< 30 years OR = 3.48, 95%CI 1.85-6.56; 30-70 years OR = 3.08, 95%CI 2.01-4.71), first-degree relationship with the proband (OR = 16.61, 95%CI 10.50-26.28) and segregation of the PV in both the maternal (OR = 2.54, 95%CI 1.72-3.75) and the paternal branch (OR = 4.62, 95%CI 3.09-6.91). These real-world data may be important to inform the design and implementation of strategies aimed at improving the uptake of HBOC cascade testing in Italy.

Understanding familial risk of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a deadly disease that is the result of an accumulation of sequential genetic alterations. These genetic alterations can either be inherited, such as pathogenic germline variants that are associated with an increased risk of cancer, or acquired, such as somatic mutations that occur during the lifetime of an individual. Understanding the genetic basis of inherited risk of PDAC is essential to advancing patient care and outcomes through improved clinical surveillance, early detection initiatives, and targeted therapies. In this review we discuss factors associated with an increased risk of PDAC, the prevalence of genetic variants associated with an increased risk in patients with PDAC, estimates of PDAC risk in carriers of pathogenic germline variants in genes associated with an increased risk of PDAC. The role of common variants in pancreatic cancer risk will also be discussed.

Systematic review of the molecular basis of hereditary breast and ovarian cancer syndrome in Brazil: the current scenario

BACKGROUND

A detailed understanding of the genetic basis of cancer is of great interest to public health monitoring programs. Although many studies have been conducted in Brazil, a global view on the molecular profile related to hereditary breast and ovarian cancer (HBOC) in this large and heterogeneous population is lacking.

METHODS

A systematic review following the PRISMA guidelines was conducted in three electronic databases (PubMed, BIREME and SciELO). Brazilian studies covering molecular analysis of genes related to HBOC, published until December 2023, were considered.

RESULTS

We identified 35 original studies that met all the inclusion criteria. A total of 137 distinct mutations were found in the BRCA1 gene, but four of them corresponded to 44.5% of all mutations found in this gene. The c.5266dupC BRCA1 mutation was responsible for 26.8% of all pathogenic mutations found in the BRCA1 gene in patients with clinical criteria for HBOC from the Brazilian population. Considering all studies that track this mutation in the BRCA1 gene, we found a frequency of 2% (120/6008) for this mutation in Brazilian patients. In the BRCA2 gene, the four most frequent mutations corresponded to 29.2% of pathogenic mutations. Even though it was tracked by few studies, the c.156_157insAlu mutation was responsible for 9.6% of all pathogenic mutations reported in the BRCA2 gene. Seventeen studies found pathogenic mutations in other non-BRCA genes, the c.1010G > A mutation in the TP53 gene being the most frequent one. Considering all studies that screened for this specific mutation in patients with the clinical criteria for HBOC, the frequency of c.1010G > A was estimated at 1.83% (61/3336).

CONCLUSIONS

Despite significant molecular heterogeneity among mutations in HBOC patients from Brazil, three mutations deserve to be highlighted, c.5266dupC, c.156_157insAlu and c.1010G > A in the BRCA1, BRCA2 and TP53 genes, respectively. With more than 200 records, these three mutations play a vital role in the pathology of breast and ovarian cancer in Brazil. The data collected shed light on the subject, but there is still not enough data from certain subpopulations.

Genome Engineering as a Therapeutic Approach in Cancer Therapy: A Comprehensive Review

Cancer is one of the foremost causes of mortality. The human genome remains stable over time. However, human activities and environmental factors have the power to influence the prevalence of certain types of mutations. This goes to the excessive progress of xenobiotics and industrial development that is expanding the territory for cancers to develop. The mechanisms involved in immune responses against cancer are widely studied. Genome editing has changed the genome-based immunotherapy process in the human body and has opened a new era for cancer treatment. In this review, recent cancer immunotherapies and the use of genome engineering technology are largely focused on.

Hereditary breast cancer next-generation sequencing (NGS) panel evaluation in the south region of Brazil: a novel BRCA2 candidate pathogenic variant is reported

In this article, we delineate a loosely selected cohort comprising patients with a history of early-onset breast cancer and/or a familial occurrence of cancer. The aim of this study was to gain insights into the presence of breast cancer-related gene variants in a population from a micro-region in southern Brazil, specifically the Metropolitan Region of Curitiba. This area exhibits a highly genetically mixed population, mirroring the general characteristics of the Brazilian people. Comprehensive next-generation sequencing (NGS) multigene panel testing was conducted, involving the evaluation of twelve patients. Two pathogenic variants and one candidate pathogenic variant were identified: BRCA2:c.8878C>T, p.Gln2960Ter; CHEK2:c.1100delAG>A, p.Thr367Metfs*15 and BRCA2:c.3482dupG>GA, p.Asp1161Glufs*3, a novel variant, previously unpublished, is reported.

Patient-reported outcomes in bilateral prophylactic mastectomy with breast reconstruction: A narrative review

In women at high risk of developing breast cancer, bilateral prophylactic mastectomy (BPM) 1 significantly reduces the risk; simultaneously, breast reconstruction preserves body integrity. Given the complex and personal nature of such surgical procedures, patient assessment of satisfaction and health-related quality of life (HRQoL) 2 is essential in evaluation of surgical outcomes. With this review, we aim to organize the current knowledge on patient-reported outcomes (PROs) 3 in bilateral prophylactic surgery. Literature search was conducted using the databases Google Scholar, PubMed, and Web of Science to address the following questions, which can help clinicians and women undergoing the procedures navigate their healthcare decision-making process: How does BPM with reconstruction influence cancer-related distress? How does the surgery impact patient satisfaction and HRQoL? How do preoperative PROs differ from postoperative outcomes? Does the type of BPM and the type of reconstruction impact patient satisfaction and HRQoL? Furthermore, we summarize available patient-reported outcome measures (PROMs) 4 that can be administered to women undergoing BPM with reconstruction. In addition, we discuss possible future directions for PRO research in prophylactic breast surgery.

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.

Recurrent BRCA2 exon 3 deletion in Assyrian families

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

Association Between Germline BRCA1/2 Gene Variants and Clinicopathological Features of Ovarian Cancer

Objective

To investigate the relationship between BRCA1/2 gene mutation and clinicopathological features in ovarian cancer patients, so as to develop precise individualized treatment plan for patients.

Methods

Patients diagnosed with ovarian cancer between January 2018 and July 2023 who underwent BRCA1/2 genetic testing were retrospectively analyzed. The clinicopathological characteristics (age, body mass index (BMI), family history of ovarian cancer, pregnancy history, menopause status, tumor size, histopathology, Federation of Gynecology and Obstetrics (FIGO) staging, and ascites) of non-carriers and BRCA1/2 variant carriers were compared. Logistic regression analysis was used to explore the relationship between BRCA1/2 variants and clinicopathological characteristics of ovarian cancer.

Results

A total of 284 ovarian cancer patients were collected, and the subjects were divided into two groups, 197 non-carriers and 87 BRCA1/2 variants carriers. The proportion of serous ovarian carcinoma in BRCA1/2 variant carriers is higher than that in non-BRCA variant carriers (78.2% vs 60.9%, p=0.015). There were 51 patients with BRCA pathogenic or likely pathogenic variant, 22 patients with BRCA likely benign variant, and 14 patients with BRCA variants of uncertain significance (VUS). The proportion of serous ovarian carcinoma in patients with BRCA pathogenic/likely pathogenic variant is higher than that in patients with BRCA likely benign variant and BRCA VUS (94.1% vs 50.0% and 64.3%. p<0.001). There were no statistically significant differences in BMI, family history of ovarian cancer, pregnancy history, menopause status, maximum diameter of the tumor lesion, FIGO stage, and ascites among patients with different grades of variants. Multivariate logistic regression analysis showed that serous ovarian carcinoma was related to BRCA mutation (Serous carcinoma vs non-serous carcinoma: OR 2.145, 95% CI: 1.044-4.407) (p=0.038).

Conclusion

Patients with BRCA1 variant develop ovarian cancer at a younger age than those with the BRCA2 variant. The proportion of FIGO stage III-IV in patients with BRCA pathogenic + likely pathogenic variant was significantly higher than those in patients with other variants. Germline BRCA1/2 variants were most frequently identified in serous ovarian carcinoma patients.

Prevalence and Distribution of MUTYH Pathogenic Variants, Is There a Relation with an Increased Risk of Breast Cancer?

BACKGROUND

MUTYH has been implicated in hereditary colonic polyposis and colorectal carcinoma. However, there are conflicting data refgarding its relationship to hereditary breast cancer. Therefore, we aimed to assess if MUTYH mutations contribute to breast cancer susceptibility.

METHODS

We retrospectively reviewed 3598 patients evaluated from June 2018 to June 2023 at the Hereditary Cancer Unit of La Paz University Hospital, focusing on those with detected MUTYH variants.

RESULTS

Variants of MUTYH were detected in 56 patients (1.6%, 95%CI: 1.2-2.0). Of the 766 patients with breast cancer, 14 patients were carriers of MUTYH mutations (1.8%, 95%CI: 0.5-3.0). The prevalence of MUTYH mutation was significantly higher in the subpopulation with colonic polyposis (11.3% vs. 1.1%, p < 0.00001, OR = 11.2, 95%CI: 6.2-22.3). However, there was no significant difference in the prevalence within the subpopulation with breast cancer (1.8% vs. 1.5%, p = 0.49, OR = 1.2, 95%CI: 0.7-2.3).

CONCLUSION

In our population, we could not establish a relationship between MUTYH and breast cancer. These findings highlight the necessity for a careful interpretation when assessing the role of MUTYH mutations in breast cancer risk.

The Genetic Paradigm of Hereditary Breast and Ovarian Cancer (HBOC) in the Afro-Caribbean Population

Differences in tumor biology and genetic predisposition have been suggested as factors influencing overall survival and increased mortality in Black breast and ovarian cancer patients. Therefore, it is key to evaluate genetic susceptibilities in Afro-Caribbean patients because the black population in the US is not homogeneous. Identifying a high incidence of hereditary breast and ovarian cancer (HBOC) in Afro-Caribbean countries can lead to understanding the pattern of inherited traits in US-Caribbean immigrants and their subsequent generations. The paucity of projects studying the genetic landscape in these populations makes it difficult to design studies aimed at optimizing screening and prophylaxis strategies, which in turn, improve survival and mortality rates. This scoping review identifies and categorizes current research on the genetic paradigm of HBOC in the Afro-Caribbean population. We performed an evaluation of the evidence and generated a summary of findings according to preferred reporting items for systematic review and meta-analysis (PRISMA) Extension for Scoping Reviews guidelines. We included articles that assessed the incidence and prevalence of pathologic germline mutations and experience/barriers for genetic testing in Afro-Caribbean Countries and US-Caribbean patients. Our results highlight countries where genetic landscapes remain severely understudied and support recommending multigene testing in Caribbean-born patients. They highlight a need for further research on the genetic paradigm of HBOC in the Afro-Caribbean population to improve genetic testing/counseling and the subsequent adoption of early detection and risk reduction strategies.

Primary Peritoneal Carcinosarcoma in a Breast Cancer Patient Harboring a Germline BRCA2 Pathogenic Variant: Case Report

Malignant mixed müllerian tumor (MMMT) is a rare neoplasm, consisting of carcinomatous (epithelial) and sarcomatous (mesenchymal) components that most commonly arise in the endometrium and more infrequently in the ovaries, fallopian tube, cervix, and vagina. Primary peritoneal carcinosarcoma (PPCS) is an extremely rare extragenital presentation of MMMT. Although the occurrence of breast cancer and epithelial ovarian carcinoma in association with BRCA pathogenic variants is firmly established, the etiologic role of these genes in the development of other tumor types is less well known. Here, we present a rare case of PPCS in a 42-year-old Brazilian woman with a BRCA2 pathogenic variant, c.2808_2811del (NM_000059.3). The patient developed metastatic breast cancer at the age of 37 and underwent a risk-reducing bilateral salpingo-oophorectomy 2 years later. She was then diagnosed with PPCS 3 years after the risk-reducing surgery. She underwent treatment with surgery, chemotherapy, and targeted therapy but passed away almost 5 years after the second primary tumor diagnosis. To our knowledge, this is the first case of peritoneal carcinosarcoma described in a BRCA2 pathogenic variant carrier, and its report leads to a better understanding of the disease's molecular features and possible therapeutic approaches.

A cost-utility analysis of BRCA1 and BRCA2 testing in high-risk breast cancer patients and family members in Thailand: a cost-effective policy in resource-limited settings

Background

Screening for germline pathogenic BRCA1 or BRCA2 variants (gBRCA) in high-risk breast cancer patients is known to be cost-effective in high-income countries. Nationwide adoption of genetics testing in high-risk breast cancer population remains poor. Our study aimed to assess gBRCA health economics data in the middle-income country setting of Thailand.

Methods

Decision tree and Markov model were utilized to assess cost-utility between the testing vs. no-testing groups from a societal and lifetime perspective and lifetime. We interviewed 264 patients with breast/ovarian cancer and their family members to assess relevant costs and quality of life using EQ-5D-5L. One-way sensitivity, probabilistic sensitivity (Monte Carlo simulation), and budget impact analyses were done to estimate the outcome under Thailand's Universal Health Coverage scheme.

Results

The predicted lifetime cost and Quality-adjusted Life Years (QALY) for those with breast cancer were $13,788 and 10.22 in the testing group and $13,702 and 10.07 in the no-testing group. The incremental cost-effectiveness ratio for gBRCA testing in high-risk breast cancer patients was $573/QALY. The lifetime cost for the family members of those with gBRCA was $14,035 (QALY 9.99), while the no-testing family members group was $14,077 (QALY 9.98). Performing gBRCA testing in family members was cost-saving.

Conclusion

Cost-utility analysis demonstrated a cost-effective result of gBRCA testing in high-risk breast cancer patients and cost-saving in familial cascade testing. The result was endorsed in the national health benefits package in 2022. Other middle-income countries may observe the cost-effective/cost-saving aspects in common genetic diseases under their national health schemes.

Susceptibility Genes Associated with Multiple Primary Cancers

With advancements in treatment and screening techniques, we have been witnessing an era where more cancer survivors harbor multiple primary cancers (MPCs), affecting approximately one in six patients. Identifying MPCs is crucial for tumor staging and subsequent treatment choices. However, the current clinicopathological criteria for clinical application are limited and insufficient, making it challenging to differentiate them from recurrences or metastases. The emergence of next-generation sequencing (NGS) technology has provided a genetic perspective for defining multiple primary cancers. Researchers have found that, when considering multiple tumor pairs, it is crucial not only to examine well-known essential mutations like MLH1/MSH2, EGFR, PTEN, BRCA1/2, CHEK2, and TP53 mutations but also to explore certain pleiotropic loci. Moreover, specific deleterious mutations may serve as regulatory factors in second cancer development following treatment. This review aims to discuss these susceptibility genes and provide an explanation of their functions based on the signaling pathway background. Additionally, the association network between genetic signatures and different tumor pairs will be summarized.

Hereditary breast and ovarian cancer: from genes to molecular targeted therapies

Hereditary familial tumors constitute 10-15% of all malignancies and present opportunities for the identification of therapeutic approaches against specific germline genetic defects. Hereditary breast and ovarian cancer (HBOC) syndrome, which is linked to the pathogenic mutations of the breast cancer 1 (BRCA1) and breast cancer 2 (BRCA2) genes, is an important research model for personalized therapeutic approaches for specific germline mutations. HBOC is characterized by multiple cases of breast and ovarian carcinoma in association with other tumors (prostate, pancreas and stomach carcinoma) within the same family branch, a young age of onset (<36 years), bilaterality and an autosomal dominant pattern of inheritance. Counseling, evaluation of the clinical criteria for the diagnosis of HBOC, and the performance of genetic testing allow for the identification of subjects with BRCA1/2 mutations and provide crucial information for clinical and therapeutic management. The identification of a BRCA gene mutation has therapeutic implications for women with metastatic and non-metastatic breast cancer. In the therapeutic setting of BRCA+ breast cancer, treatment with poly (ADP-ribose) polymerase (PARP) inhibitors, which keep cancer cells from repairing their damaged DNA and cause cell death, is remarkable. This review summarizes the evidence demonstrating the value of BRCA1/2 status as a diagnostic and prognostic tool and as a predictive biomarker in the personalized approach to hereditary BRCA + cancers.

Advances in Early Breast Cancer Risk Profiling: From Histopathology to Molecular Technologies

Early breast cancer (BC) is the definition applied to breast-confined tumors with or without limited involvement of locoregional lymph nodes. While risk stratification is essential for guiding clinical decisions, it can be a complex endeavor in these patients due to the absence of comprehensive guidelines. Histopathological analysis and biomarker assessment play a pivotal role in defining patient outcomes. Traditional histological criteria such as tumor size, lymph node involvement, histological type and grade, lymphovascular invasion, and immune cell infiltration are significant prognostic indicators. In addition to the hormone receptor, HER2, and-in specific scenarios-BRCA1/2 testing, molecular subtyping through gene expression profiling provides valuable insights to tailor clinical decision-making. The emergence of "omics" technologies, applicable to both tissue and liquid biopsy samples, has broadened our arsenal for evaluating the risk of early BC. However, a pressing need remains for standardized methodologies and integrated pathological models that encompass multiple analytical dimensions. In this study, we provide a detailed examination of the existing strategies for early BC risk stratification, intending to serve as a practical guide for histopathologists and molecular pathologists.

Simultaneous bilateral mastectomy and RRSO for BRCA2-positive non-invasive breast cancer in Japan: a case report and analysis of initial experience

BACKGROUND

In Japan, genetic testing, surveillance, and risk-reducing surgery for hereditary breast and ovarian cancer (HBOC) syndrome have been covered by the Japanese national insurance system since April 2020. On the other hand, the current situation is that medical care, including surveillance of undiagnosed (cancer-free) patients, is self-funded even for individuals with HBOC. We report a case in which breast cancer was diagnosed at an early stage during surveillance for cancer-free HBOC at the patient's own expense, and risk-reducing surgery was performed at the same time as treatment for breast cancer.

CASE PRESENTATION

The patient was a 63-year-old woman. Her sister had a history of breast cancer in her 30s and was found to be a BRCA2 pathogenic variant carrier by genetic testing. The patient therefore presented to the genetic department of our hospital and underwent genetic testing (out-of-pocket). A pathogenic variant was found at the same site. During annual breast and ovarian surveillance at the patient's own expense, a physician with sufficient expertise in contrast-enhanced breast magnetic resonance imaging (MRI) noticed a change in the contrast enhancement pattern on breast MRI and performed needle biopsy, revealing ductal carcinoma in situ. At the request of the patient, she underwent concurrent contralateral risk-reducing mastectomy and risk-reducing salpingo-oophorectomy in addition to breast cancer treatment.

CONCLUSIONS

We encountered a case in which cancer treatment and risk-reducing surgery were performed at the same time for a pathogenic variant carrier who was very anxious about developing cancer. Surveillance of cancer-free BRCA1/2 mutation carriers and expansion of insurance coverage for surgery are important future issues.

Public Awareness and Acceptability of PGT-M in Cancer Predisposition Syndromes

Cancer Predisposition Syndromes (CPSs), also known as Hereditary Cancer Syndromes (HCSs), represent a group of genetic disorders associated with an increased lifetime risk of developing cancer. In this article, we provide an overview of the reproductive options for patients diagnosed with CPS, focusing on the emerging role of Preimplantation Genetic Testing for Monogenic disorders (PGT-M). Specifically, we conducted a literature review about the awareness and acceptability of its application to CPSs. Based on the available data, the awareness of the applicability of PGT-M for CPSs appears to be limited among both patients and physicians, and a heterogeneous set of factors seems to influence the acceptability of the procedure. Our findings highlight the need for increasing education about the use of PGT-M for CPSs. In this context, guidelines developed by professional or institutional bodies would represent a useful reference tool to assist healthcare professionals in providing proper preconception counseling.

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.

Landscape of somatic mutated genes and inherited susceptibility genes in gynecological cancer

Traditionally, gynecological cancers have been classified based on histology. Since remarkable advancements in next-generation sequencing technology have enabled the exploration of somatic mutations in various cancer types, comprehensive sequencing efforts have revealed the genomic landscapes of some common forms of human cancer. The genomic features of various gynecological malignancies have been reported by several studies of large-scale genomic cohorts, including The Cancer Genome Atlas. Although recent comprehensive genomic profiling tests, which can detect hundreds of genetic mutations at a time from cancer tissues or blood samples, have been increasingly used as diagnostic clinical biomarkers and in therapeutic management decisions, germline pathogenic variants associated with hereditary cancers can also be detected using this test. Gynecological cancers are closely related to genetic factors, with approximately 5% of endometrial cancer cases and 20% of ovarian cancer cases being caused by germline pathogenic variants. Hereditary breast and ovarian cancer syndrome and Lynch syndrome are the two major cancer susceptibility syndromes among gynecological cancers. In addition, several other hereditary syndromes have been reported to be associated with gynecological cancers. In this review, we highlight the genes for somatic mutation and germline pathogenic variants commonly seen in gynecological cancers. We first describe the relationship between clinicopathological attributes and somatic mutated genes. Subsequently, we discuss the characteristics and clinical management of inherited cancer syndromes resulting from pathogenic germline variants in gynecological malignancies.

Double Heterozygosity for Rare Deleterious Variants in the BRCA1 and BRCA2 Genes in a Hungarian Patient with Breast Cancer

Hereditary breast cancer is most commonly attributed to germline BRCA1 and BRCA2 gene variants. The vast majority of BRCA1 and BRCA2 mutation carriers are single heterozygotes, and double heterozygosity (DH) is a very rare finding. Here, we describe the case of a BRCA1/BRCA2 double heterozygous female proband diagnosed with breast cancer. Genetic testing for hereditary breast and ovarian cancer revealed two pathogenic variants in the BRCA1 (c.5095C>T, p.(Arg1699Trp)) and in BRCA2 genes (c.658_659delGT, p.(Val220Ilefs*4)) in heterozygous form. None of the variants were founder Jewish mutations; to our knowledge, these rare deleterious variants have not been previously described in DH patients in the literature. The patient had triple-negative unilateral breast cancer at the age of 36 and 44 years. Based on family studies, the BRCA1 variant was maternally inherited.

Finding significance: New perspectives in variant classification of the RAD51 regulators, BRCA2 and beyond

For many individuals harboring a variant of uncertain functional significance (VUS) in a homologous recombination (HR) gene, their risk of developing breast and ovarian cancer is unknown. Integral to the process of HR are BRCA1 and regulators of the central HR protein, RAD51, including BRCA2, PALB2, RAD51C and RAD51D. Due to advancements in sequencing technology and the continued expansion of cancer screening panels, the number of VUS identified in these genes has risen significantly. Standard practices for variant classification utilize different types of predictive, population, phenotypic, allelic and functional evidence. While variant analysis is improving, there remains a struggle to keep up with demand. Understanding the effects of an HR variant can aid in preventative care and is critical for developing an effective cancer treatment plan. In this review, we discuss current perspectives in the classification of variants in the breast and ovarian cancer genes BRCA1, BRCA2, PALB2, RAD51C and RAD51D.

Long-Term Outcomes of Breast Cancer Patients with Local Recurrence After Mastectomy Undergoing Immediate Breast Reconstruction: A Retrospective Multi-institutional Study of 4153 Cases

BACKGROUND

The number of breast cancer patients in Japan undergoing immediate breast reconstruction (IBR) has increased and the postoperative follow-up period has been extended. This study was conducted to clarify the clinical aspects of, and factors associated with, local recurrence (LR) after IBR.

METHODS

This was a multicenter study which included 4153 early breast cancer patients who underwent IBR. Clinicopathological characteristics were examined and factors potentially contributing to LR were analyzed. Risk factors for LR were examined separately for non-invasive and invasive breast cancers.

RESULTS

The median follow-up period was 75 months. The 7-year LR rates were 2.1% and 4.3% for non-invasive and invasive cancers, respectively (p < 0.001). The proportions of LR detected by palpation, subjective symptoms, and ultrasonography were 40.0%, 27.3%, and 25.9%, respectively. Overall, 75.7% of LR were solitary, and 92.7% of these cases had no further recurrences during the observational period. Multivariate analysis of LR for invasive cancer showed that skin-sparing mastectomy (SSM) or nipple-sparing mastectomy (NSM), the presence of lymphovascular invasion, cancer at the surgical margin, and not receiving radiation therapy were factors related to LR. The 7-year overall survival rates of the patients with LR and non-LR of invasive cancers were 92.5% and 97.3%, respectively, (p = 0.002).

CONCLUSIONS

The rate of LR after IBR was acceptably low and IBR can thus be performed safely for early breast cancer patients. Invasive cancer, SSM/NSM, lymphovascular invasion, and/or cancer at the surgical margin should prompt awareness of the possibility of LR.

Personalized medicine with germline pathogenic variants: Importance of population- and region-wide evidence

Rare germline pathogenic variants in cancer-predisposing genes have a high impact and potential for clinical utility. In the last 30 years, based on evidence of cancer risk associated with germline pathogenic variants, several measures have been suggested for personalized medicine, including the development of novel treatments, treatment stratification, risk reduction by surgical measures, chemoprevention, removal of environmental factors, and surveillance for early detection among specific high-risk individuals. However, this evidence is mainly based on evaluations of European populations. Our large-scale analyses of more than 100,000 individuals, including 14 disease cases and non-cancer controls in the Japanese population, suggest some discrepancies in the associations between cancer-predisposing genes and diseases, expansion of the targeted diseases of BRCA1 and BRCA2, and a potential novel risk-reduction measure for gastric cancer. They are likely to be explained by population and region variations; therefore, more population-wide and region-wide research could provide improved personalized medicine as well as a better understanding of disease mechanisms. This review summarizes current personalized medicine and discusses the potential use of germline pathogenic variants.

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.

Diagnostics and treatment of ovarian cancer in the era of precision medicine - opportunities and challenges

Due to predictions of increasing incidences and deaths from ovarian cancer, this neoplasm is a challenge for modern health care. The advent of NGS technology has made it possible to understand the molecular characteristics of many cancers, including ovarian cancer. The data obtained in research became the basis for the development of molecularly targeted therapies thus leading to the entry of NGS analysis into the diagnostic process of oncological patients. This review presents targeted therapies currently in preclinical or clinical trials, whose promising results offer hope for their use in clinical practice in the future. As more therapeutic options emerge, it will be necessary to modify molecular diagnostic regimens to select the best treatment for a given patient. New biomarkers are needed to predict the success of planned therapy. An important aspect of public health is molecular testing in women with a familial predisposition to ovarian cancer enabling patients to be included in prevention programs. NGS technology, despite its high throughput, poses many challenges, from the quality of the diagnostic material used for testing to the interpretation of results and classification of sequence variants. The article highlights the role of molecular testing in ongoing research and also its role in the diagnostic and therapeutic process in the era of personalized medicine. The spread of genetic testing in high-risk groups, the introduction of more targeted therapies and also the possibility of agnostic therapies could significantly improve the health situation for many women worldwide.

The Tumor Suppressor BRCA1/2, Cancer Susceptibility and Genome Instability in Gynecological and Mammary Cancers

BRCA1 and BRCA2 germline alterations highly predispose women to breast and ovarian cancers. They are mostly found within the TNBC (Triple-Negative Breast Cancer) and the HGSOC (High-Grade Serous Ovarian Carcinoma) subsets, known by an aggressive phenotype, the lack of therapeutic targets and poor prognosis. Importantly, there is an increased risk for cervical cancer in BRCA1 and BRCA2 mutation carriers that raises questions about the link between the HPV-driven genome instability and BRCA1 and BRCA2 germline mutations. Clinical, preclinical, and in vitro studies explained the increased risk for breast and ovarian cancers by genome instability resulting from the lack or loss of many functions related to BRCA1 or BRCA2 proteins such as DNA damage repair, stalled forks and R-loops resolution, transcription regulation, cell cycle control, and oxidative stress. In this review, we decipher the relationship between BRCA1/2 alterations and genomic instability leading to gynecomammary cancers through results from patients, mice, and cell lines. Understanding the early events of BRCA1/2-driven genomic instability in gynecomammary cancers would help to find new biomarkers for early diagnosis, improve the sensitivity of emerging therapies such as PARP inhibitors, and reveal new potential therapeutic targets.

Prophylactic Risk-Reducing Mastectomy (PRRM): A Set Practice or Catch-22 Situation in LMIC. A Single-Centre Prospective Cohort Study

Background Pakistan's hereditary breast cancer has a higher-than-average prevalence. Our acceptability of prophylactic risk-reducing mastectomy (PRRM) still needs to be determined, and genetic testing still needs to be offered to all eligible. The aim is to determine the number of women presenting to our centre who availed of PRRM after positive genetic tests and the main reasons restraining them from considering PRRM.Materials and methods This study is a single-centre, prospective cohort. We collected data from 2017 to 2022 on BRCA1/2 and other (P/LP) gene-positive patients. Continuous variables are presented as means (±SD) and categorical variables in percentages, with a significant P-value of ≤ 0.05.Results Out of 477 tested individuals, only 95(20.12%) had a positive result. BRCA1/2 was positive in 70 cases, while P/LP variants were in 24 cases. Only 32.6% of eligible families underwent genetic testing, with 54.8% positivity. Altogether, 92.6% of patients had BRCA1/2-related cancers. Only 25/95(26.3%) individuals availed of PRRM, the majority had contralateral risk-reducing mastectomy 68% with a 20% reconstruction rate. The main reasons to decline PRRM were false belief of not having any disease 57.44%, followed by family/spouse pressure 51%, body appearance/societal perception, fear of complications/quality of life and financial constraints.Conclusion Genetic testing and its implications are still a grey area for LMICs, primarily due to the scarcity of centres offering genetic testing to eligible populations, followed by prevalent perceptions about prophylactic surgeries among the masses. Addressing relevant issues in LMICs is the need of time.

Copy Number Variations (CNVs) Account for 10.8% of Pathogenic Variants in Patients Referred for Hereditary Cancer Testing

BACKGROUND/AIM

Germline copy number variation (CNV) is a type of genetic variant that predisposes significantly to inherited cancers. Today, next-generation sequencing (NGS) technologies have contributed to multi gene panel analysis in clinical practice.

MATERIALS AND METHODS

A total of 2,163 patients were screened for cancer susceptibility, using a solution-based capture method. A panel of 52 genes was used for targeted NGS. The capture-based approach enables computational analysis of CNVs from NGS data. We studied the performance of the CNV module of the commercial software suite SeqPilot (JSI Medical Systems) and of the non-commercial tool panelcn.MOPS. Additionally, we tested the performance of digital multiplex ligation-dependent probe amplification (digitalMLPA).

RESULTS

Pathogenic/likely pathogenic variants (P/LP) were identified in 464 samples (21.5%). CNV accounts for 10.8% (50/464) of pathogenic variants, referring to deletion/duplication of one or more exons of a gene. In patients with breast and ovarian cancer, CNVs accounted for 10.2% and 6.8% of pathogenic variants, respectively. In colorectal cancer patients, CNV accounted for 28.6% of pathogenic/likely pathogenic variants.

CONCLUSION

In silico CNV detection tools provide a viable and cost-effective method to identify CNVs from NGS experiments. CNVs constitute a substantial percentage of P/LP variants, since they represent up to one of every ten P/LP findings identified by NGS multigene analysis; therefore, their evaluation is highly recommended to improve the diagnostic yield of hereditary cancer analysis.

BRCA1 Promoter Hypermethylation in Malignant Breast Tumors and in the Histologically Normal Adjacent Tissues to the Tumors: Exploring Its Potential as a Biomarker and Its Clinical Significance in a Translational Approach

The hypermethylation status of the promoter region of the breast cancer 1 (BRCA1), a well-known tumor suppressor gene, has been extensively investigated in the last two decades as a potential biomarker for breast cancer. In this retrospective study, we investigated the prevalence of BRCA1 promoter methylation in 84 human breast tissues, and we correlated this epigenetic silencing with the clinical and histopathological parameters of breast cancer. We used methylation-specific PCR (MSP) to analyze BRCA1 promoter hypermethylation in 48 malignant breast tumors (MBTs), 15 normal adjacent tissues (NATs), and 21 benign breast lesions (BBLs). The results showed that BRCA1 promoter hypermethylation was higher in MBTs (20/48; 41.67%) and NATs (7/15; 46.67%) compared to BBLs (4/21; 19.05%). The high percentage of BRCA1 hypermethylation in the histologically normal adjacent tissues to the tumors (NATs) suggests the involvement of this epigenetic silencing as a potential biomarker of the early genomic instability in NATs surrounding the tumors. The detection of BRCA1 promoter hypermethylation in BBLs reinforces this suggestion, knowing that a non-negligible rate of benign breast lesions was reported to evolve into cancer. Moreover, our results indicated that the BRCA1 promoter hypermethylated group of MBTs exhibited higher rates of aggressive features, as indicated by the SBR III grade (14/19; 73.68%), elevated Ki67 levels (13/16; 81.25%), and Her2 receptor overexpression (5/20; 25%). Finally, we observed a concordance (60%) in BRCA1 promoter hypermethylation status between malignant breast tumors and their paired histologically normal adjacent tissues. This study highlights the role of BRCA1 promoter hypermethylation as a potential useful biomarker of aggressiveness in MBTs and as an early marker of genomic instability in both histological NATs and BBLs.

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%.

Co-Occurrence of Germline Genomic Variants and Copy Number Variations in Hereditary Breast and Colorectal Cancer Patients

Hereditary Breast and Ovarian Cancer (HBOC) syndrome is an autosomal dominant disease associated with a high risk of developing breast, ovarian, and other malignancies. Lynch syndrome is caused by mutations in mismatch repair genes predisposing to colorectal and endometrial cancers, among others. A rare phenotype overlapping hereditary colorectal and breast cancer syndromes is poorly characterized. Three breast and colorectal cancer unrelated patients fulfilling clinical criteria for HBOC were tested by whole exome sequencing. A family history of colorectal cancer was reported in two patients (cases 2 and 3). Several variants and copy number variations were identified, which potentially contribute to the cancer risk or prognosis. All patients presented copy number imbalances encompassing PMS2 (two deletions and one duplication), a known gene involved in the DNA mismatch repair pathway. Two patients showed gains covering the POLE2 (cases 1 and 3), which is associated with DNA replication. Germline potentially damaging variants were found in PTCH1 (patient 3), MAT1A, and WRN (patient 2). Overall, concurrent genomic alterations were described that may increase the risk of cancer appearance in HBOC patients with breast and colorectal cancers.

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.

Overview of the Genetic Causes of Hereditary Breast and Ovarian Cancer Syndrome in a Large French Patient Cohort

The use of multigene panel testing for patients with a predisposition to Hereditary Breast and Ovarian Cancer syndrome (HBOC) is increasing as the identification of mutations is useful for diagnosis and disease management. Here, we conducted a retrospective analysis of BRCA1/2 and non-BRCA gene sequencing in 4630 French HBOC suspected patients. Patients were investigated using a germline cancer panel including the 13 genes defined by The French Genetic and Cancer Group (GGC)-Unicancer. In the patients analyzed, 528 pathogenic and likely pathogenic variants (P/LP) were identified, including BRCA1 (n = 203, 38%), BRCA2 (n = 198, 37%), PALB2 (n = 46, 9%), RAD51C (n = 36, 7%), TP53 (n = 16, 3%), and RAD51D (n = 13, 2%). In addition, 35 novel (P/LP) variants, according to our knowledge, were identified, and double mutations in two distinct genes were found in five patients. Interestingly, retesting a subset of BRCA1/2-negative individuals with an expanded panel produced clinically relevant results in 5% of cases. Additionally, combining in silico (splicing impact prediction tools) and in vitro analyses (RT-PCR and Sanger sequencing) highlighted the deleterious impact of four candidate variants on splicing and translation. Our results present an overview of pathogenic variations of HBOC genes in the southeast of France, emphasizing the clinical relevance of cDNA analysis and the importance of retesting BRCA-negative individuals with an expanded panel.

Mitochondrial Deoxyribonucleic Acid (mtDNA), Maternal Inheritance, and Their Role in the Development of Cancers: A Scoping Review

Mitochondrial DNA (mtDNA) is a small, circular, double-stranded DNA inherited from the mother during fertilization. Evolutionary evidence supported by the endosymbiotic theory identifies mitochondria as an organelle that could have descended from prokaryotes. This may be the reason for the independent function and inheritance pattern shown by mtDNA. The unstable nature of mtDNA due to the lack of protective histones, and effective repair systems make it more vulnerable to mutations. The mtDNA and its mutations could be maternally inherited thereby predisposing the offspring to various cancers like breast and ovarian cancers among others. Although mitochondria are considered heteroplasmic wherein variations among the multiple mtDNA genomes are noticed, mothers can have mitochondrial populations that are homoplasmic for a given mitochondrial mutation. Homoplasmic mitochondrial mutations may be transmitted to all maternal offspring. However, due to the complex interplay between the mitochondrial and nuclear genomes, it is often difficult to predict disease outcomes, even with homoplasmic mitochondrial populations. Heteroplasmic mtDNA mutations can be maternally inherited, but the proportion of mutated alleles differs markedly between offspring within one generation. This led to the genetic bottleneck hypothesis, explaining the rapid changes in allele frequency witnessed during the transmission of mtDNA from one generation to the next. Although a physical reduction in mtDNA has been demonstrated in several species, a comprehensive understanding of the molecular mechanisms is yet to be demonstrated. Despite initially thought to be limited to the germline, there is evidence that blockages exist in different cell types during development, perhaps explaining why different tissues in the same organism contain different levels of mutated mtDNA. In this review, we comprehensively discuss the potential mechanisms through which mtDNA undergoes mutations and the maternal mode of transmission that contributes to the development of tumors, especially breast and ovarian cancers.

Exploring the Burden of Cancer in Pakistan: An Analysis of 2019 Data

Cancer has become a growing burden in Pakistan in recent times, posing a significant cause for concern. The World Health Organization has reported a steady increase in the incidence of cancer in Pakistan. According to the present study, breast cancer (24.1%), oral cavity (9.6%), colorectum (4.9%), esophagus (4.2%), and liver cancer (3.9%) were the five most prevalent cancers. Males were more likely to have oral cavity cancer (14.9%), colorectum cancer (6.8%), liver cancer (6.4%), prostate cancer (6.0%), and lung cancer (6.0%). In women (41.6%), breast (6.9%), oral cavity (5.5%), cervix (4.7%), and uterus cancer (4.1%) were the most common cancers. Middle-aged people (43.0%) were most likely to develop cancer, followed by seniors (30.0%) and adults (20.0%). Children and adolescents were most likely to develop cancers of the central nervous system (CNS), leukemia (18.7%), and Hodgkin (17.3%), followed by breast, oral cavity, colorectum, and prostate at other ages. Most patients were from Punjab (40.4%) and Sindh (32.2%). Approximately 30.0% of patients were diagnosed at stage III and stage IV. In terms of registered cases, breast cancer, oral cavity cancer, colon cancer, esophagus cancer, and liver cancer are among the highest. In the future, this information may prove useful for assessing the effectiveness of interventions.

PALB2 germline mutations in a large cohort of Middle Eastern breast-ovarian cancer patients

The PALB2 gene is a breast cancer (BC) and ovarian cancer (OC) predisposition gene involved in the homologous recombination repair pathway. However, the prevalence and clinicopathological association of PALB2 pathogenic/likely pathogenic (PV/LPV) variants in Middle East is still not fully explored. Total 918 BC/OC patients from Saudi Arabia were selected for PALB2 mutations screening using capture sequencing technology. Five heterozygous PVs or LPVs were identified in six cases, accounting for 0.65% (6/918) of entire cohort. Two cases (33.3%) harbored PVs and four cases (66.7%) carried LPVs. Four PVs/LPVs (80%) were frameshift along with one novel splicing LPV (c.2835-2_2835-1delinsTT). One recurrent LPV (c.3425delT: p.L1142fs) was identified in two cases. All six affected carriers have breast cancer diagnosis with median age of 39.5 years (range 34-49 years). Only two cases (33%) have documented family history of cancer. Breast cancer phenotype was invasive ductal unilateral cancer in all cases with 66.7% of hormone receptor positive and 16% of triple negative tumors. Germline PVs/LPVs in the PALB2 gene were observed in low frequency of 0.65% in Saudi BC and/or OC. Our study confirms one recurrent LPV and one novel LPV in Saudi breast cancer patients.

Privacy and utility of genetic testing in families with hereditary cancer syndromes living in three countries: the international cascade genetic screening experience

Background: Hereditary breast and ovarian cancer and Lynch syndrome are associated with increased lifetime risk for common cancers. Offering cascade genetic testing to cancer-free relatives of individuals with HBOC or LS is a public health intervention for cancer prevention. Yet, little is known about the utility and value of information gained from cascade testing. This paper discusses ELSI encountered during the implementation of cascade testing in three countries with national healthcare systems: Switzerland, Korea, and Israel. Methods: A workshop presented at the 5th International ELSI Congress discussed implementation of cascade testing in the three countries based on exchange of data and experiences from the international CASCADE cohort. Results: Analyses focused on models of accessing genetic services (clinic-based versus population-based screening), and models of initiating cascade testing (patient-mediated dissemination versus provider-mediated dissemination of testing results to relatives). The legal framework of each country, organization of the healthcare system, and socio-cultural norms determined the utility and value of genetic information gained from cascade testing. Conclusion: The juxtaposition of individual versus public health interests generates significant ELSI controversies associated with cascade testing, which compromise access to genetic services and the utility and value of genetic information, despite national healthcare/universal coverage.