Results of a population-based screening for hereditary breast cancer in a region of North-Central Italy: contribution of BRCA1/2 germ-line mutations

Evaluation of an Italian Population-Based Programme for Risk Assessment and Genetic Counselling and Testing for BRCA1/2-Related Hereditary Breast and Ovarian Cancer after 10 Years of Operation: An Observational Study Protocol

Hereditary breast/ovarian cancer (HBOC) syndrome is caused by the inheritance of monoallelic germline BRCA1/2 gene mutations. If BRCA1/2 mutation carriers are identified before the disease develops, effective actions against HBOC can be taken, including intensive screening, risk-reducing mastectomy and salpingo-oophorectomy, and risk-reducing medications. The Italian National Prevention Plan mandates the creation of regional BRCA genetic testing programmes. So far, however, only informal data have been reported on their implementation. We have designed a study aimed at evaluating the results of a population-based programme for risk assessment and genetic counselling and testing for BRCA1/2-related HBOC that is underway in the Emilia-Romagna region (northern Italy). The programme-which is entirely free-includes basic screening with an estimate of the likelihood of carrying a BRCA1/2 mutation using a familial risk assessment tool, a closer examination of women with suspected risk increase, an assessment of the need for further genetic counselling and, if needed, genetic testing and risk-reducing interventions. In this paper, the design of the programme and the protocol of the study are presented. The study has an observational, historical cohort design. Eligible are the women found to be at an increased risk of HBOC (profile 3 women). The main objectives are (i) to determine the precision of the programme in measuring the level of risk of HBOC for profile 3 women; (ii) to determine the characteristics of profile 3 women and their association with the risk management strategy chosen; (iii) to compare the age at onset, histologic type, tumour stage, molecular subtype, and prognosis of breast/ovarian cancers observed in the cohort of profile 3 women with the features of sporadic cancers observed in the general female population; (iv) to determine the level and the determinants of adherence to recommendations; and (v) to determine the appropriateness and timing of risk-reducing surgery and medications. Investigating the quality and results of the programme is necessary because the best practices in risk assessment and genetic counselling and testing for BRCA1/2-related cancer and the challenges they encounter should be identified and shared. The study has the potential to provide sound empirical evidence for the factors affecting the effectiveness of this type of service.

Using species richness calculations to model the global profile of unsampled pathogenic variants: Examples from BRCA1 and BRCA2

There have been many surveys of genetic variation in BRCA1 and BRCA2 to identify variant prevalence and catalogue population specific variants, yet none have evaluated the magnitude of unobserved variation. We applied species richness estimation methods from ecology to estimate "variant richness" and determine how many germline pathogenic BRCA1/2 variants have yet to be identified and the frequency of these missing variants in different populations. We also estimated the prevalence of germline pathogenic BRCA1/2 variants and identified those expected to be most common. Data was obtained from a literature search including studies conducted globally that tested the entirety of BRCA1/2 for pathogenic variation. Across countries, 45% to 88% of variants were estimated to be missing, i.e., present in the population but not observed in study data. Estimated variant frequencies in each country showed a higher proportion of rare variants compared to recurrent variants. The median prevalence estimate of BRCA1/2 pathogenic variant carriers was 0.64%. BRCA1 c.68_69del is likely the most recurrent BRCA1/2 variant globally due to its estimated prevalence in India. Modeling variant richness using ecology methods may assist in evaluating clinical targeted assays by providing a picture of what is observed with estimates of what is still unknown.

Prevalence and Spectrum of Germline BRCA1 and BRCA2 Variants of Uncertain Significance in Breast/Ovarian Cancer: Mysterious Signals From the Genome

About 10–20% of breast/ovarian (BC/OC) cancer patients undergoing germline BRCA1/2 genetic testing have been shown to harbor Variants of Uncertain Significance (VUSs). Since little is known about the prevalence of germline BRCA1/2 VUS in Southern Italy, our study aimed at describing the spectrum of these variants detected in BC/OC patients in order to improve the identification of potentially high-risk BRCA variants helpful in patient clinical management. Eight hundred and seventy-four BC or OC patients, enrolled from October 2016 to December 2020 at the “Sicilian Regional Center for the Prevention, Diagnosis and Treatment of Rare and Heredo-Familial Tumors” of University Hospital Policlinico “P. Giaccone” of Palermo, were genetically tested for germline BRCA1/2 variants through Next-Generation Sequencing analysis. The mutational screening showed that 639 (73.1%) out of 874 patients were BRCA-w.t., whereas 67 (7.7%) were carriers of germline BRCA1/2 VUSs, and 168 (19.2%) harbored germline BRCA1/2 pathogenic/likely pathogenic variants. Our analysis revealed the presence of 59 different VUSs detected in 67 patients, 46 of which were affected by BC and 21 by OC. Twenty-one (35.6%) out of 59 variants were located on BRCA1 gene, whereas 38 (64.4%) on BRCA2. We detected six alterations in BRCA1 and two in BRCA2 with unclear interpretation of clinical significance. Familial anamnesis of a patient harboring the BRCA1-c.3367G>T suggests for this variant a potential of pathogenicity, therefore it should be carefully investigated. Understanding clinical significance of germline BRCA1/2 VUS could improve, in future, the identification of potentially high-risk variants useful for clinical management of BC or OC patients and family members.

Initiatives to Scale Up and Expand Reach of Cancer Genomic Services Outside of Specialty Clinical Settings: A Systematic Review

CONTEXT

This systematic review aims to (1) characterize strategies used to identify individuals at increased risk for hereditary breast and ovarian cancer syndrome and Lynch syndrome outside of oncology and clinical genetic settings, (2) describe the extent to which these strategies have extended the reach of genetic services to underserved target populations, and (3) summarize indicators of the potential scalability of these strategies.

EVIDENCE ACQUISITION

Investigators searched PubMed, EMBASE, and PsycINFO for manuscripts published from October 2005 to August 2019. Eligible manuscripts were those published in English, those that described strategies to identify those at risk for hereditary breast and ovarian cancer syndrome or Lynch syndrome, those implemented outside of an oncology or genetic specialty clinic, and those that included measures of cancer genetic services uptake. This study assessed strategies used to increase the reach of genetic risk screening and counseling services. Each study was evaluated using the 16-item quality assessment tool, and results were reported according to the PRISMA guidelines.

EVIDENCE SYNTHESIS

Of the 16 eligible studies, 11 were conducted in clinical settings and 5 in public health settings. Regardless of setting, most (63%, 10/16) used brief screening tools to identify people with a family history suggestive of hereditary breast and ovarian cancer syndrome or Lynch syndrome. When reported, genetic risk screening reach (range =11%-100%) and genetic counseling reach (range =11%-100%) varied widely across studies. Strategies implemented in public health settings appeared to be more successful (median counseling reach=65%) than those implemented in clinical settings (median counseling reach=26%). Most studies did not describe fundamental components relevant for broad scalability.

CONCLUSIONS

Efforts to expand cancer genomic services are limited outside of traditional oncology and genetic clinics. This is a missed opportunity because evidence thus far suggests that these efforts can be successful in expanding the reach of genetic services with the potential to reduce health inequities in access. This review highlights the need for accelerating research that applies evidence-based implementation strategies and frameworks along with process evaluation to understand barriers and facilitators to scalability of strategies with high reach.

BRCA1 and BRCA2 genes mutations among high risk breast cancer patients in Jordan

Familial breast cancer is estimated to account for 15-20% of all cases of breast cancer. Surveillance for familial breast cancer is well-established world-wide. However, this service does not exist in Jordan, due to the scarcity of information with regard to the genetic profiling of these patients, and therefore lack of recommendations for policy-makers. As such, patients with very strong family history of breast or ovarian cancers are not screened routinely; leading to preventable delay in diagnosis. Whole coding sequencing for BCRA1/BCRA2 using next-generation sequencing (NGS)/Ion PGM System was performed. Sanger sequencing were then used to confirm the pathogenic variants detected by NGS. In this study, 192 breast cancer patients (and 8 ovarian cancer cases) were included. The prevalence of recurrent pathogenic mutations was 14.5%, while the prevalence of newly detected mutations was 3.5%. Two novel pathogenic mutations were identified in BRCA2 genes. The common mutations in the Ashkenazi population used for screening may not apply in the Jordanian population, as previously reported mutations were not prevalent, and other new mutations were identified. These data will aid to establish a specific screening test for BRCA 1/BRCA2 in the Jordanian population.

A regional population-based hereditary breast cancer screening tool in Italy: First 5-year results

Background

Up to 10% of individuals with breast cancer (BC) belong to families with hereditary syndromes. The aim of this study was to develop an instrument to identify individuals/families at high‐hereditary risk for BC and offer dedicated surveillance programs according to different risks.

Methods

The instrument consisted of a primary questionnaire collecting history of BC and ovarian cancer (OC). This questionnaire was applied to women enrolled in the Emilia‐Romagna Breast Cancer Screening Program. General practitioners (GPs) and specialists could propose the same questionnaire too. Women with a score of ≥ 2, were invited to complete an oncogenetic counseling. According to the Tyrer‐Cuzick evaluation, women considered at high risk were invited to involve the most representative alive individual of the family affected with BC/OC for BRCA1/2 genetic testing.

Results

Since January 2012 and December 2016, 660 040 women were evaluated by the regional screening program, of which 22 289 (3.5%) were invited to the Spoke evaluation, but only 5615 accepted (25.2%). Totally, also considering women sent by GPs and specialists, 11 667 were assessed and 5554 were sent to the Hub evaluation. Finally, 2342 (42.8%) women fulfilled the criteria for genetic testing, and 544 (23.2%) resulted BRCA1/2 mutation carriers.

Conclusions

To our knowledge, this is the first regional population‐based multistep model that is aimed to identify individuals with BRCA1/2 mutations and to offer an intensive surveillance program for hereditary‐high risk women. This tool is feasible and effective, even if more efforts must be performed to increase the acceptance of multiple assessments by the study population.

BRCA-associated ovarian cancer: from molecular genetics to risk management

Ovarian cancer (OC) mostly arises sporadically, but a fraction of cases are associated with mutations in BRCA1 and BRCA2 genes. The presence of a BRCA mutation in OC patients has been suggested as a prognostic and predictive factor. In addition, the identification of asymptomatic carriers of such mutations offers an unprecedented opportunity for OC prevention. This review is aimed at exploring the current knowledge on epidemiological and molecular aspects of BRCA-associated OC predisposition, on pathology and clinical behavior of OC occurring in BRCA mutation carriers, and on the available options for managing asymptomatic carriers.