The relationship between BRCA-associated breast cancer and age factors: an analysis of the Japanese HBOC consortium database

Risk-reducing decisions regarding germline BRCA pathogenic variant: focusing on the timing of genetic testing and RRSO

BACKGROUND

In Japan, the public insurance policy was revised in 2020 to cover hereditary breast and ovarian cancer (HBOC), including genetic testing and surveillance, for patients with breast cancer (BC). Consequently, the demand for risk-reducing salpingo-oophorectomy (RRSO) has increased. This study aimed to clarify the changes in the demand and timing of genetic testing and RRSO associated with public insurance coverage for HBOC in Japan.

METHODS

This retrospective analysis included 350 women with germline BRCA (gBRCA) pathogenic variants (PVs) who had visited gynaecologists; they received gBRCA genetic testing at 45.1±10.6 (20-74) years. The use of medical testing and preventive treatment was compared between the preinsurance and postinsurance groups using Mann-Whitney U and Fisher's exact tests.

RESULTS

The findings indicate that RRSO rates doubled from 31.4% to 62.6% among patients with gBRCA-PV. The implementation rate was 32.4% among unaffected carriers and 70.3% among BC-affected patients. Younger patients received genetic testing with significantly shorter intervals between BC diagnosis and genetic testing and between genetic testing and RRSO.

CONCLUSION

Overall, the insurance coverage for HBOC patients with BC has increased the frequency of RRSO in Japan. However, a comparison between the number of probands and family members indicated that the diagnosis among family members is inadequate. The inequality in the use of genetic services by socioeconomic groups is an issue of further concern.

The Japanese Breast Cancer Society clinical practice guidelines for epidemiology and prevention of breast cancer, 2022 edition

The Japanese Breast Cancer Society Clinical Practice Guidelines for Epidemiology and Prevention of Breast Cancer, 2022 Edition.

Positive and negative regulators of RAD51/DMC1 in homologous recombination and DNA replication

RAD51 recombinase plays a central role in homologous recombination (HR) by forming a nucleoprotein filament on single-stranded DNA (ssDNA) to catalyze homology search and strand exchange between the ssDNA and a homologous double-stranded DNA (dsDNA). The catalytic activity of RAD51 assembled on ssDNA is critical for the DNA-homology-mediated repair of DNA double-strand breaks in somatic and meiotic cells and restarting stalled replication forks during DNA replication. The RAD51-ssDNA complex also plays a structural role in protecting the regressed/reversed replication fork. Two types of regulators control RAD51 filament formation, stability, and dynamics, namely positive regulators, including mediators, and negative regulators, so-called remodelers. The appropriate balance of action by the two regulators assures genome stability. This review describes the roles of positive and negative RAD51 regulators in HR and DNA replication and its meiosis-specific homolog DMC1 in meiotic recombination. We also provide future study directions for a comprehensive understanding of RAD51/DMC1-mediated regulation in maintaining and inheriting genome integrity.

A Japanese case of ovarian mucinous adenocarcinoma with germline double variants of MSH2 and BRCA2

Germline double heterozygosity (GDH) is rarely reported in cases of inherited cancer syndromes, and GDH of a mismatch repair gene and BRCA has never been reported in Japan. Nonetheless, the current report demonstrates a case of ovarian mucinous adenocarcinoma with initiated Lynch syndrome (LS)-related surveillance because of a known germline MSH2 variant. Six and a half years after oophorectomy, multiple tumors developed in the patient's lungs, bones, and lymph nodes, and histology results confirmed mucinous adenocarcinoma. Systemic chemotherapy including an anti-PD-L1 antibody was effective for >1 year, but brain metastases developed. Pathology of the brain tumors showed mucinous adenocarcinoma without expression of MSH2 and MSH6, while multi-gene panel testing demonstrated not only high microsatellite instability and a high tumor mutation burden, but also germline BRCA2 variants. Further, germline testing in relatives confirmed both variants were from the paternal line, from which many LS-related cancers develop, but not BRCA-related cancer.

A transcriptional response to replication stress selectively expands a subset of Brca2-mutant mammary epithelial cells

Germline BRCA2 mutation carriers frequently develop luminal-like breast cancers, but it remains unclear how BRCA2 mutations affect mammary epithelial subpopulations. Here, we report that monoallelic Brca2mut/WT mammary organoids subjected to replication stress activate a transcriptional response that selectively expands Brca2mut/WT luminal cells lacking hormone receptor expression (HR-). While CyTOF analyses reveal comparable epithelial compositions among wildtype and Brca2mut/WT mammary glands, Brca2mut/WT HR- luminal cells exhibit greater organoid formation and preferentially survive and expand under replication stress. ScRNA-seq analysis corroborates the expansion of HR- luminal cells which express elevated transcript levels of Tetraspanin-8 (Tspan8) and Thrsp, plus pathways implicated in replication stress survival including Type I interferon responses. Notably, CRISPR/Cas9-mediated deletion of Tspan8 or Thrsp prevents Brca2mut/WT HR- luminal cell expansion. Our findings indicate that Brca2mut/WT cells activate a transcriptional response after replication stress that preferentially favours outgrowth of HR- luminal cells through the expression of interferon-responsive and mammary alveolar genes.

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

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

BRCA 1/BRCA 2 Pathogenic/Likely Pathogenic Variant Patients with Breast, Ovarian, and Other Cancers

The demographic and clinical characteristics of patients who have BRCA 1/BRCA 2 pathogenic/likely pathogenic variants may differ from their relatives who had BRCA-related cancer. In this study, we aimed to demonstrate the clinical and demographic findings of patients who had BRCA-related cancer and to assess the differences comparing their relatives who had BRCA-related cancer with breast, genital tract, prostate, and pancreas cancers as well. The results of sequencing analysis of 200 cancer patients (190 women, 10 men) who have been directed to genetic counseling with an indication of BRCA1/BRCA2 testing from different regions across 9 medical oncology centers were retrospectively analyzed. A total of 200 consecutive cancer patients who harbored the BRCA1/BRCA2 pathogenic/likely pathogenic variant (130 (65%) patients harbored BRCA 1 pathogenic/likely pathogenic variant, and 70 harbored BRCA 2 pathogenic/likely pathogenic variant) were included. Of these, 64.0% had breast cancer (43.8% of them had the triple-negative disease, and about 2.3% had only the HER-2 mutant), 31.5% had genital cancers (92.1% of them had ovarian cancer, 3.2% had endometrium, and 1.6% had peritoneum cancer as the primary site and mostly serous adenocarcinoma was the most common histopathology and 14.3% of the patients had endometrioid adenocarcinoma), 3.5% had prostate (median time from metastasis to castration-resistant status was 28 months) and 1.0% had pancreas cancer. Newly diagnosed cancer (breast and ovary) patients who had BRCA 1/BRCA 2 pathogenic/ likely pathogenic variant were younger than their previous cancer diagnosed (breast, ovary, and pancreas) parents who harbored BRCA pathogenic/likely pathogenic variant. We suggest that the genetic screening of BRCA 1/ BRCA 2 pathogenic/likely pathogenic variant is needed as a routine screening for those with a personal or family history of breast, ovarian, tubal, or peritoneal cancer. In addition, once BRCA 1 or BRCA 2 germline pathogenic variant has been identified in a family, testing of at-risk next-generation relatives earlier can identify those family members who also have the familial pathogenic variant, and thus need increased surveillance.

Promoters of BRCA testing under insurance coverage for non-metastatic breast cancer patients in Japan: a retrospective cohort study

BACKGROUND

We investigated the barriers to and promoters of taking BRCA testing, after the start of national healthcare insurance coverage for non-metastatic breast cancer patients in Japan.

PATIENTS AND METHODS

This was a multi-center, retrospective, cohort study. We included stage 0 to III breast cancer patients who were diagnosed and met the criteria for insurance coverage of BRCA testing between April 2020 and December 2021. We examined the association between BRCA testing and possible exposures: breast cancer diagnosis at 45 years or younger, triple-negative breast cancer (TNBC) diagnosis at the age of 60 or younger, two or more primary breast cancers, family history of breast cancer or ovarian cancer in the third degree of relatives, male breast cancer, medical expense limits, and parity. We used logistic regression analysis.

RESULTS

We included 222 patients and 123 (55.4%) of them underwent the test. In univariate analysis, a family history of ovarian cancer (odds ratio (OR) 10.59; 95% CI 1.35-82.96, p = 0.025), diagnosis of breast cancer at the age of 45 or younger (OR 2.78; 95% CI 1.52-5.14, p = 0.0009), and diagnosis of TNBC at the age of 60 or younger (OR 3.95; 95% CI 1.55-10.07, p = 0.004) were associated with taking the test. After multivariate logistic regression analysis, a family history of ovarian cancer (adjusted OR 12.80; 95% CI 1.51-108.80, p = 0.0195), diagnosis of breast cancer at the age of 45 or younger (adjusted OR 4.43; 95% CI 1.98-9.90, p = 0.0003), and TNBC at the age of 60 or younger (adjusted OR 5.28; 95% CI 1.90-14.66, p = 0.0014) were consistently associated.

CONCLUSION

For non-metastatic breast cancer patients whose BRCA testing is covered by insurance, costs would no longer be a definite barrier. Physicians should keep in mind that a family history of ovarian cancer, breast cancer diagnosis at 45 years of age or younger and TNBC diagnosis at 60 years of age or younger are strong promoters.

The performance of multi-gene panels for breast/ovarian cancer predisposition

BRCA1 and BRCA2 are the most mutated genes in breast cancer. We analyzed 48 breast cancer subjects using two methods that differ in terms of number of genes investigated and strategy used (primers: Panel A - 12 genes - vs probes: Panel B - 48 genes). Both the panels and procedures identified "pathogenic" or "likely pathogenic" variants in TP53, ATM, CHEK2 and BARD1 besides BRCA1 and BRCA2. Panel B identified two other putatively pathogenic variants in RNASEL and in RAD50. Identification of variants other than the BRCA genes can be useful in patient management. A total of 121 variants were distributed within the 12 genes and were correctly detected by both panels. However, the number of calls without divergence, namely ± 0.10 difference of allelic frequency, was 78.3%, while calls with a divergence below 0.10 was 16.7%, thus indicating that only 5% (n = 275) of 5,412 calls had a divergence above 0.10. Although these panels differ from each other, both are useful in different situations, particularly when patients should be tested for genes other than BRCA1/2 (as occurs in patients affected by a so called hereditary syndrome) or for therapeutic purposes.

Using publicly available datasets to identify population-based transcriptomic landscape contributing to the aggressiveness of breast cancer in young women

Introduction: Although the risk of breast cancer increases with advancing age, some regions have larger number of young breast cancer patients (≤45 years-old), such as the Middle East, Eastern Asia, and North Africa, with more aggressive and poorly differentiated tumors. We aimed to conduct an in-silico analysis in an attempt to understand the aggressive nature of early-onset breast cancer, and to identify potential drivers of early-onset breast cancer using gene expression profiling datasets in a population-dependent manner. Methods: Functional genomics experiments data were acquired from cBioPortal database for cancer genomics, followed by the stratification of patients based on the age at representation of breast cancer and race. Differential gene expression analysis and gene amplification status analysis were carried out, followed by hub gene, transcription factor, and signalling pathway identification. Results: PAM50 subtype analysis revealed that young patients (≤45 years-old) had four-fold more basal tumors and worst progression-free survival (median of 101 months), compared with the 45-65 years group (median of 168 months). Fourteen genes were amplified in more than 14% of patients with an early-onset breast cancer. Interestingly, FREM2, LINC00332, and LINC00366 were exclusively amplified in younger patients. Gene expression data from three different populations (Asian, White, and African) revealed a unique transcriptomic profile of young patients, which was also reflected on the PAM50 subtype analysis. Our data indicates a higher tendency of young African patients to develop basal tumors, while young Asian patients are more prone to developing Luminal A tumors. Most genes that were found to be upregulated in younger patients are involved in important signaling pathways that promote cancer progression and metastasis, such as MAPK pathway, Reelin pathway and the PI3K/Akt pathway. Conclusion: This study provides strong evidence that the molecular profile of tumors derived from young breast cancer patients of different populations is unique and may explain the aggressiveness of these tumors, stressing the need to conduct population- based multi-omic analyses to identify the potential drivers for tumorigenesis and molecular profiles of young breast cancer patients.

Acquired Treatment Resistance in a Patient with Metastatic PD-L1-Positive Breast Cancer and Germline BRCA1 Mutation

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer associated with higher rates of relapse and mortality compared to other subtypes. Chemotherapy has been a mainstream treatment approach for TNBC due to the lack of therapeutic targets. Recent advances have led to the introduction of novel agents against specific patients with programmed death-ligand 1 (PD-L1)-positive TNBC who harbor germline BRCA mutations. However, some patients who respond to PD-L1 or poly (ADP-ribose) polymerase PARP inhibitors often develop resistance. Additionally, treatment strategies are more complicated for patients with PD-L1-positive TNBC and germline BRCA mutations. Here, we report a patient with metastatic PD-L1-positive TNBC who harbored a germline BRCA1 mutation. The patient sequentially received combination treatment regimens, including PD-L1 inhibitors with chemotherapy and the PARP inhibitor olaparib, acquiring resistance to the treatments in a couple of months. Further investigations are warranted to elucidate the mechanisms underlying resistance to PD-L1 antibodies and PARP inhibitors to improve treatment outcomes while preventing emergence of treatment resistance in patients with TNBC.

Physical Activity in Young BRCA Carriers and Reduced Risk of Breast Cancer

INTRODUCTION

A systematic literature review was conducted to determine whether physical activity levels during adolescent and young adult years were associated with a reduced lifetime risk of breast cancer among carriers of deleterious mutations in BRCA1 and BRCA2 genes.

METHODS

Ovid/MEDLINE, Embase, CENTRAL, WOS, and CINAHL were searched for articles including information about adolescent and young adult physical activity and breast cancer incidence among women carrying deleterious BRCA1 and BRCA2 gene mutations (search was initiated in October 2019; last update and full analyses were in March 2021). Independent reviewers screened articles at the title/abstract and full-text levels, resolving differences by consensus with lead authors. The NIH Quality Assessment Tools were used to assess sources of bias.

RESULTS

A total of 1,957 unique articles were identified; 5 met inclusion criteria. Samples size ranged from 68 to 1,185. All studies relied on self-reported adolescent and young adult physical activity. One study measured sports involvement; the others measured recreational activity. One large study was null, whereas 4 others showed a reduction in breast cancer incidence later in life with higher adolescent and young adult physical activity (p≤0.05). However, the protection was limited to premenopausal breast cancer in 1 of the studies (OR=0.62; 95% CI=0.40, 0.96; p-trend=0.01). In addition, adolescent and young adult physical activity was associated with older age at breast cancer diagnosis in 1 study (p=0.03).

CONCLUSIONS

A limited number of studies suggest that adolescent and young adult physical activity may reduce or delay the risk of breast cancer incidence among carriers of deleterious mutations in BRCA1 and BRCA2 genes.

An Overview on Radiation Sensitivity in Hereditary Breast and Ovarian Cancer Syndrome

Simple Summary

Individuals with hereditary breast and ovarian cancer (HBOC) syndrome are more likely to develop several types of cancer compared to the general population. They are regularly subjected to diagnostic exams and therapeutic options that use ionizing radiation, making it important to understand the effects that this can induce. Thus, several studies have been carried out to understand whether the exposure of individuals with HBOC to ionizing radiation may be associated with the onset of cancer. However, the results are inconsistent.

Abstract

Hereditary breast and ovarian cancer (HBOC) syndrome is a condition in which individuals have an increased risk of developing different types of cancer when compared to the general population. BRCA1 repair associated (BRCA1) and BRCA2 repair associated (BRCA2) genes are tumor suppressor genes that play a crucial role in cell, by repairing DNA damage. Mutations in these genes are responsible for 25% of HBOC cases. Individuals with this syndrome are often subjected to diagnostic imaging techniques, as well as therapeutic options, that use ionizing radiation, so it is crucial to understand whether these individuals may present higher radiosensitivity and, therefore, its consequences. Several studies have been carried out to understand if the exposure to different ionizing radiation doses can induce cancer in individuals with HBOC. Some of these studies have shown that individuals with HBOC are hypersensitive to the ionizing radiation and, therefore, have neoplasms resulting from mutations in genes that are important in maintaining genomic stability. When mutated, genes no longer guarantee this stability and promote the induction of carcinogenesis. Oppositely, other studies show that there is no association between exposure to ionizing radiation and an increased risk of developing cancer. Thus, the results are inconsistent, and there is a great need to clarify this relationship. In this review, we present the characteristics of HBOC syndrome and the effects that ionizing radiation can induce in individuals who have it. In addition, we review the studies that have already been carried out on this subject.

The genetics of hereditary cancer risk syndromes in Brazil: a comprehensive analysis of 1682 patients

Hereditary cancer risk syndromes are caused by germline variants, commonly in tumor suppressor genes. Most studies on hereditary cancer have been conducted in white populations. We report the largest study in Brazilian individuals with multiple ethnicities. We genotyped 1682 individuals from all country regions with Next-generation sequencing (NGS) panels. Most were women with a personal/family history of cancer, mostly breast and ovarian. We identified 321 pathogenic/likely pathogenic (P/LP) variants in 305 people (18.1%) distributed among 32 genes. Most were on BRCA1 and BRCA2 (129 patients, 26.2% and 14.3% of all P/LP, respectively), MUTYH (42 monoallelic patients, 13.1%), PALB2 (25, 7.8%), Lynch syndrome genes (17, 5.3%), and TP53 (17, 5.3%). Transheterozygosity prevalence in our sample was 0.89% (15/1682). BRCA1/BRCA2 double heterozygosity rate was 0.78% (1/129) for BRCA variants carriers and 0.06% (1/1682) overall. We evaluated the performance of the genetic testing criteria by NCCN and the Brazilian National Health Agency (ANS). The inclusion criteria currently used in Brazil fail to identify 17%-25% of carriers of P/LP variants in hereditary cancer genes. Our results add knowledge on the Brazilian spectrum of cancer risk germline variants, demonstrate that large multigene panels have high positivity rates, and indicate that Brazilian inclusion criteria for genetic testing should be improved.

Is adjuvant chemotherapy necessary in older patients with breast cancer?

BACKGROUND

Due to the lack of clinical trials on the efficacy of chemotherapy in older patients, an optimal treatment strategy has not been developed. We investigated whether adjuvant chemotherapy could improve the survival of older patients with breast cancer in Japan.

METHODS

We retrospectively analyzed data of patients with breast cancer aged ≥ 70 years who underwent breast cancer surgery in eight hospitals between 2008 and 2013. Clinical treatment and follow-up data were obtained from the patients' medical electric records.

RESULTS

A total of 1095 patients were enrolled, of which 905 were included in the initial non-matched analysis. The median age and follow-up period were 75 (range 70-93) and 6.3 years, respectively. Of these patients, 127 (14%) received adjuvant chemotherapy (Chemo group) while the remaining 778 (86%) did not (Control group). The Chemo group was younger (mean age in years 73 vs 76; P < 0.0001), had a larger pathological tumor size (mean mm 25.9 vs 19.9; P < 0.0001), and more metastatic axillary lymph nodes (mean numbers 2.7 vs 0.7; P < 0.0001) than the Control group. The disease-free survival (DFS) and overall survival (OS) did not differ significantly between the two groups (P = 0.783 and P = 0.558). After matched analyses, DFS was found to be significantly prolonged with adjuvant chemotherapy (P = 0.037); however, OS difference in the matched cohort was not statistically significant (P = 0.333).

CONCLUSION

The results showed that adjuvant chemotherapy was associated with a reduced risk of recurrence, but survival benefits were limited.

Investigating the Anticancer Potential of Salvicine as a Modulator of Topoisomerase II and ROS Signaling Cascade

Salvicine is a new diterpenoid quinone substance from a natural source, specifically in a Chinese herb. It has powerful growth-controlling abilities against a broad range of human cancer cells in both in vitro and in vivo environments. A significant inhibitory effect of salvicine on multidrug-resistant (MDR) cells has also been discovered. Several research studies have examined the activities of salvicine on topoisomerase II (Topo II) by inducing reactive oxygen species (ROS) signaling. As opposed to the well-known Topo II toxin etoposide, salvicine mostly decreases the catalytic activity with a negligible DNA breakage effect, as revealed by several enzymatic experiments. Interestingly, salvicine dramatically reduces lung metastatic formation in the MDA-MB-435 orthotopic lung cancer cell line. Recent investigations have established that salvicine is a new non-intercalative Topo II toxin by interacting with the ATPase domains, increasing DNA-Topo II interaction, and suppressing DNA relegation and ATP hydrolysis. In addition, investigations have revealed that salvicine-induced ROS play a critical role in the anticancer-mediated signaling pathway, involving Topo II suppression, DNA damage, overcoming multidrug resistance, and tumor cell adhesion suppression, among other things. In the current study, we demonstrate the role of salvicine in regulating the ROS signaling pathway and the DNA damage response (DDR) in suppressing the progression of cancer cells. We depict the mechanism of action of salvicine in suppressing the DNA-Topo II complex through ROS induction along with a brief discussion of the anticancer perspective of salvicine.

Differences in age at diagnosis of ovarian cancer for each BRCA mutation type in Japan: optimal timing to carry out risk-reducing salpingo-oophorectomy

Objective

BRCA1 and BRCA2 mutation carriers are recommended to undergo risk-reducing salpingo-oophorectomy (RRSO) by age 40 and 45, respectively. However, the carriers have a different way of thinking about their life plan. We aimed to investigate the distribution of age at diagnosis of ovarian cancer (OC) patients to examine the optimal timing of RRSO in the carriers.

Methods

We examined a correlation between age at diagnosis of OC and common mutation types in 3,517 probands that received BRCA genetic testing. Among them, germline BRCA1 mutation (gBRCA1m), germline BRCA2 mutation (gBRCA2m) and germline BRCA wild-type (gBRCAwt) were found in 185, 42 and 241 OC patients, respectively.

Results

The average age at diagnosis of OC in gBRCA1m and gBRCA2m was 51.3 and 58.3 years, respectively, and the difference from gBRCAwt (53.8 years) was significant. The gBRCA2m carriers did not develop OC under the age of 40. The average age was 50.1 years for L63X and 52.8 years for Q934X in BRCA1, and 55.1 years for R2318X and 61.1 years for STOP1861 in BRCA2. The age at diagnosis in L63X or R2318X carriers was relatively younger than other BRCA1 or BRCA2 carriers, however their differences were not significant. With L63X and R2318X carriers, 89.4% (42/47) and 100% (7/7) of women were able to prevent the development of OC, respectively, when RRSO was performed at age 40.

Conclusion

There appears to be no difference in the age at diagnosis of OC depending on the type of BRCA common mutation. Further analysis would be needed.

This is the first report to present the optimal timing of risk-reducing salpingo-oophorectomy for each BRCA mutation type in Japan. The average age at diagnosis of ovarian cancer (OC) in germline BRCA2 mutation (gBRCA2m) is higher than that in germline BRCA wild-type. The gBRCA2m carriers did not develop OC under the age of 40. The average age at diagnosis in L63X or R2318X carriers was relatively younger than other BRCA mutation carriers, though the differences were not significant.

Comparing breast cancer imaging characteristics of CHEK2 with BRCA1 and BRCA2 gene mutation carriers

PURPOSE

Breast cancer gene (BRCA) 1 and 2 mutations are frequently studied gene mutations (GM); the incidence of checkpoint kinase 2 (CHEK2) is increasing. We describe the imaging features of breast cancer (BC) in CHEK2 mutations, compared to BRCA 1 and 2 using mammography, ultrasound (US) and magnetic resonance imaging (MRI).

METHOD

Inclusion criteria were primary BC in GM carriers, treated in the same hospital. Age at diagnosis, histology, hormone receptor and human epidermal growth factor receptor 2 (HER2) status were retrieved. Mammography descriptors were mass, asymmetry and suspicious microcalcifications. The enhancement pattern (MRI), shape and border, architectural distortion, the presence of a hyperechoic rim and cystic complex structure (US) were documented. Analyses were performed using SAS software (version 9.4). Fishers' exact test was used to test associations between two categorical variables.

RESULTS

In 191 women, 233 malignant lesions were diagnosed (78 in BRCA1, 109 in BRCA2, 46 in CHEK2). In CHEK2 carriers, mammographically, suspicious microcalcifications (54%) were more prevalent (BRCA2 (48%) and BRCA1 carriers (33%)) (p-value = 0.057) compared to mass lesions (35%). On US, lesions were most frequently ill-defined (86%) (p = 0.579) and irregular (94.5%) (p = 0.098) compared to BRCA2 (77% and 80% resp.) and BRCA1 carriers (71% and 72% resp.). On MRI, mass lesions showed a type 3 curve in CHEK2 (67%) compared to BRCA1 (36%) and BRCA2 (50%) (p = 0.056).

CONCLUSIONS

Malignant radiological characteristics of breast cancer, more specifically suspicious microcalcifications, were more frequently seen in CHEK2 and BRCA2 compared to BRCA1 mutation carriers (without a significant difference) indicating the importance of mammography in follow-up of CHEK2 carriers.

Japanese women's reasons for accompaniment status to hereditary breast and ovarian cancer-focused genetic counseling

Genetic counselors routinely assess and understand clients' needs at the beginning of a session. Attending a genetic counseling session with or without companions is an objective sign that genetic counselors can easily notice. This study focused on clients' reasons for their accompaniment status for genetic counseling, which we categorize into attending with or without a companion(s). A questionnaire survey and interviews were conducted using snowball sampling, starting with the chief executive officer (CEO) of the Japanese hereditary breast and ovarian cancer (HBOC) support group. Of 32 participants, 19 continued with an in-depth interview after answering the questionnaire. Five themes were identified from the interview: (1) personal confidence, (2) decision-making style, (3) family members' habits and time availability, (4) considerations and conflicts with family members, and (5) healthcare provider's suggestion. Our data suggested that the clients expected their companion(s) to play certain roles. This indicates that the reasons of accompaniment status will be helpful for genetic counselors to understand both clients' and their families' motivations, personalities, habits, and psychosocial backgrounds. In a high-context culture such as that of Japan, accompaniment status may be a helpful sign to understand clients' true worries. In addition, some companions may be future clients in genetic counseling, due to the genetic nature of the disease. In conclusion, our study indicated that it is important for genetic counselors to record accompaniment status before the initial genetic counseling and to pay attention to its reasons at the beginning of the session, which may lead them to understand the client's psychosocial background to facilitate better client-centered genetic counseling.

Cancer Spectrum, Family History of Cancer and Overall Survival in Men with Germline BRCA1 or BRCA2 Mutations

BACKGROUND: Men with germline BRCA1/2 mutations are not well studied compared to their female counterparts. This study evaluates the cancer characteristics, family history of cancer, and outcomes of male BRCA1/2 mutation carriers. METHODS: All men with germline BRCA1/2 mutations who attended genetic assessment between October 1995 and October 2019 at the Medical University of Vienna were identified. Clinicohistopathological features, family history of cancer, and outcomes were assessed by mutation status. RESULTS: Of the 323 men included, 45 (13.9%) had a primary cancer diagnosis, many of whom were BRCA2 carriers (75.5%). Breast cancer (BC) was the most common cancer (57.8%) followed by prostate cancer (15.6%). Invasive ductal carcinoma and hormone receptor positive tumors were the most common. Among 26 BC-affected patients, 42% did not have any relatives with cancer. Parent of origin was only known in half of the 26 men, with 42% of them inherited through the maternal lineage versus 8% through the paternal. BRCA2 carriers and those with a family history of BC had worse overall survival (20 y vs. 23 y BRCA1 carriers; P = 0.007; 19 y vs. 21 y for those without family history of BC; P = 0.036). CONCLUSION: Male BRCA2 carriers were most likely to develop cancer and had worse prognosis. In our dataset, BC was the most common cancer, likely due to referral bias. Not all mutation carriers present with BC or have a family history of cancer to warrant genetic testing.

The Genetic Analyses of French Canadians of Quebec Facilitate the Characterization of New Cancer Predisposing Genes Implicated in Hereditary Breast and/or Ovarian Cancer Syndrome Families

The French Canadian population of the province of Quebec has been recognized for its contribution to research in medical genetics, especially in defining the role of heritable pathogenic variants in cancer predisposing genes. Multiple carriers of a limited number of pathogenic variants in BRCA1 and BRCA2, the major risk genes for hereditary breast and/or ovarian cancer syndrome families, have been identified in French Canadians, which is in stark contrast to the array of over 2000 different pathogenic variants reported in each of these genes in other populations. As not all such cancer syndrome families are explained by BRCA1 and BRCA2, newly proposed gene candidates identified in other populations have been investigated for their role in conferring risk in French Canadian cancer families. For example, multiple carriers of distinct variants were identified in PALB2 and RAD51D. The unique genetic architecture of French Canadians has been attributed to shared ancestry due to common ancestors of early settlers of this population with origins mainly from France. In this review, we discuss the merits of genetically characterizing cancer predisposing genes in French Canadians of Quebec. We focused on genes that have been implicated in hereditary breast and/or ovarian cancer syndrome families as they have been the most thoroughly characterized cancer syndromes in this population. We describe how genetic analyses of French Canadians have facilitated: (i) the classification of variants in BRCA1 and BRCA2; (ii) the identification and classification of variants in newly proposed breast and/or ovarian cancer predisposing genes; and (iii) the identification of a new breast cancer predisposing gene candidate, RECQL. The genetic architecture of French Canadians provides a unique opportunity to evaluate new candidate cancer predisposing genes regardless of the population in which they were identified.

Management of patients with BRCA mutation from the point of view of a breast surgeon

Germ-line mutation in BRCA (BReast CAncer gene) 1 or BRCA2 are found in 3–4% of all women with breast cancer. These patients have a significant increased risk of breast and ovarian cancer. They are often younger when diagnosed with the mutation, and the possible breast cancer they get is often aggressive with inferior outcome. There are risk reducing strategies, and the most powerful strategy is risk reducing surgery, both risk reducing bilateral mastectomy (RRM) and risk reducing bilateral salpino-oophorectomy (PBSO). This review is meant to address breast surgery in patients with germline BRCA mutation. The guidelines and techniques applied is under continuous change and it is important for the clinicians to be well informed to provide the patient with the information needed for them to make an informed decision on what risk strategy to choose.

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Patients with germ-line mutation in BRCA1 or BRCA2 have a significant increased risk of breast and ovarian cancer.

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There are different risk reducing strategies and the most powerful strategy is risk-reducing surgery, both risk reducing bilateral mastectomy and risk reducing bilateral salpingo-oophorectomy.

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Guidelines and techniques for the risk reducing surgery of the breast are under continuous change and improvement.

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Breast conserving therapy is not associated with worse survival and is a good option for a BRCA mutation carrier diagnosed with breast cancer. Risk-reducing mastectomy can be performed in a later setting.

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The management of BRCA mutation carriers, both affected and unaffected, should be performed in a multidisciplinary team. Physicians need to be systematically educated and updated on the most recent literature.