High prevalence of deleterious BRCA1 and BRCA2 germline mutations in arab breast and ovarian cancer patients

Cancer Incidence and Mortality Estimates in Arab Countries in 2018: A GLOBOCAN Data Analysis

BACKGROUND

Arab countries are projecting increase in cancer incidence and mortality; however, there are limited studies that compare the epidemiology of cancer in Arab countries compared with other parts of the world.

METHODS

We used the 2018 Global Cancer Observatory data to compare the age-standardized incidence and mortality estimates in Arab-speaking countries to the rest of the world.

RESULTS

Rates for incidence and mortality for all cancers in Arab countries were lower than the world's rates but the incidence rates of non-Hodgkin and Hodgkin lymphoma, bladder, breast, and liver cancers were higher. Arab countries generally had higher mortality-to-incidence ratio than the world's ratio. Incidence rates, even in age-specific groups, varied between subregions of Arab countries (the Levant, Arabian Gulf, and Arab African subregions), and Iraq and Egypt, suggesting some common and unique environmental factors and possible ethnic or genetic heritages.

CONCLUSIONS

There are essential scopes for improvements in Arab countries including better treatments to reduce the high mortality-to-incidence ratio, and supporting vaccination programs and antiviral treatments that would prevent the prevalent viral infection-related cancers. The high incidence of several cancers in younger Arabs suggests genetic factors and underlines the importance of genetic epidemiology studies.

IMPACT

This study is an essential reference to evaluate and monitor the progress of national cancer initiatives in Arab countries for surveillance and prevention programs and improving clinical management. The study also provides a comprehensive snapshot of cancers in a unique region that could shed light on the interplay of environmental, lifestyle, and genetic risk factors.

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.

Management of breast cancer patients with BRCA gene mutations in Jordan: perspectives and challenges

BACKGROUND

This paper explores and discusses local challenges oncologists face for diagnosing and managing breast cancer patients with BRCA gene mutations in Jordan.

METHODS

A task force involving key opinion leaders, experts in the management of breast cancer, and stakeholders in healthcare systems where genetic testing is available in Jordan discussed current evidence and local real-life practice. The task force then formulated recommendations to achieve better patient outcomes and satisfaction based on evidence-based medicine and their clinical experience in BRCA-mutated breast cancer management.

RESULTS AND CONCLUSION

Eligibility of patients for genetic testing, physician acceptance and willingness to integrate genetic testing into routine practice is encouraging but remains restricted by testing availability and financial coverage. Until more data is available, genetic testing should be targeted for breast cancer patients based on tumor subtypes, as well as family and personal history of cancer, as per international guidelines. Whenever possible, genetic testing should aim to detect all actionable genes through a multigene panel including BRCA1/2. Major challenges faced in clinical practice in Jordan include fear of genetic discrimination and social stigmatization, as well as hesitancy toward risk-reducing surgery. Pre-testing counseling is therefore critical to promote acceptance of genetic testing. Since geneticists are in short supply in Jordan, genetic counseling can be offered through a specially trained genetic counselor or through a hybrid system that includes oncologist-based counselling. In addition to cancer prevention, germline genetic testing may assist in the selection of specific anti-cancer therapy, such as PARP inhibitors, in patients with BRCA1/2 mutation. Nationwide initiatives are also needed to ensure access to PARP inhibition therapy and provide financial coverage for genetic screening, mastectomies and reconstructive surgery across Jordan.

Germline Pathogenic Variants and Genetic Counseling by Ancestry in Patients With Epithelial Ovarian Cancer

PURPOSE

To evaluate rates of germline pathogenic/likely pathogenic variants (PVs) and genetic counseling by ancestry in patients with epithelial ovarian cancer (EOC).

METHODS

Patients with pathologically confirmed EOC who underwent clinical tumor-normal sequencing from January 1, 2015, to December 31, 2020, inclusive of germline analysis of ≥76 genes were included. Patients with newly identified PVs were referred for Clinical Genetics Service (CGS) counseling. Ancestry groups were defined using self-reported race/ethnicity and Ashkenazi Jewish (AJ) heritage. Genetic ancestry was inferred computationally using validated algorithms. Logistic regression models were built.

RESULTS

Of 1,266 patients, self-reported ancestry (AJ, 17%; Asian, 10%; Black/African American, 5.4%; Hispanic, 6.2%; non-Hispanic White, 57%; other, 0.16%; unknown, 4.0%) correlated with genetic ancestry (AJ ancestry, 18%; admixed, 10%; African, 4%; East Asian [EAS], 6%; European, 56%; Native American, 0.2%; South Asian [SAS], 4%; unknown, 2%). Germline PVs were observed in 313 (25%) patients, including 195 (15%) with PVs in EOC-associated genes. Those with PVs were younger at diagnosis (59 v 62 years; P < .001) and more likely to have high-grade serous ovarian cancer (83% v 72%; P = .009). PV prevalence varied between ancestry groups (P < .001), with highest rates in the AJ (39.9%) and Asian (26.5%) groups and similar rates (>10%) across other ancestry groups. Use of genetic ancestry demonstrated similar findings and further characterized high rates of PV in EAS/SAS groups. Younger age, high-grade serous histology, and self-reported AJ or Asian ancestry were associated with PV in an EOC-associated gene. Rates of CGS counseling for newly identified PVs were high (80%) across ancestry groups.

CONCLUSION

Rates of PV, particularly in EOC-associated genes, were high regardless of ancestry, with similar rates of counseling between groups, emphasizing the importance of universal genetic testing in all patients with EOC.

Insights on the Role of Polyphenols in Combating Cancer Drug Resistance

Chemotherapy resistance is still a serious problem in the treatment of most cancers. Many cellular and molecular mechanisms contribute to both inherent and acquired drug resistance. They include the use of unaffected growth-signaling pathways, changes in the tumor microenvironment, and the active transport of medicines out of the cell. The antioxidant capacity of polyphenols and their potential to inhibit the activation of procarcinogens, cancer cell proliferation, metastasis, and angiogenesis, as well as to promote the inhibition or downregulation of active drug efflux transporters, have been linked to a reduced risk of cancer in epidemiological studies. Polyphenols also have the ability to alter immunological responses and inflammatory cascades, as well as trigger apoptosis in cancer cells. The discovery of the relationship between abnormal growth signaling and metabolic dysfunction in cancer cells highlights the importance of further investigating the effects of dietary polyphenols, including their ability to boost the efficacy of chemotherapy and avoid multidrug resistance (MDR). Here, it is summarized what is known regarding the effectiveness of natural polyphenolic compounds in counteracting the resistance that might develop to cancer drugs as a result of a variety of different mechanisms.

DNA damage response signaling: A common link between cancer and cardiovascular diseases

DNA damage response (DDR) signaling ensures genomic and proteomic homeostasis to maintain a healthy genome. Dysregulation either in the form of down- or upregulation in the DDR pathways correlates with various pathophysiological states, including cancer and cardiovascular diseases (CVDs). Impaired DDR is studied as a signature mechanism for cancer; however, it also plays a role in ischemia-reperfusion injury (IRI), inflammation, cardiovascular function, and aging, demonstrating a complex and intriguing relationship between cancer and pathophysiology of CVDs. Accordingly, there are increasing number of reports indicating higher incidences of CVDs in cancer patients. In the present review, we thoroughly discuss (1) different DDR pathways, (2) the functional cross talk among different DDR mechanisms, (3) the role of DDR in cancer, (4) the commonalities and differences of DDR between cancer and CVDs, (5) the role of DDR in pathophysiology of CVDs, (6) interventional strategies for targeting genomic instability in CVDs, and (7) future perspective.

Germline variants profiling of BRCA1 and BRCA2 in Chinese Hakka breast and ovarian cancer patients

Objective

To investigate the prevalence and spectrum of BRCA1 and BRCA2 mutations in Chinese Hakka patients with breast and ovarian cancer.

Methods

A total of 1,664 breast or ovarian cancer patients were enrolled for genetic testing at our hospital. Germline mutations of the BRCA gene were analysed by next-generation sequencing, including the coding regions and exon intron boundary regions.

Results

The 1,664 patients included 1,415 (85.04%) breast cancer patients and 245 (14.72%) ovarian cancer patients, while four (0.24%) patients had both the breast and ovarian cancers. A total of 151 variants, including 71 BRCA1 variants and 80 BRCA2 variants, were detected in the 234 (14.06%) patients. The 151 variants included 58 pathogenic variants, 8 likely pathogenic variants, and 85 variants of unknown significance (VUS). A total of 56.25% (18/32) and 65.38% (17/26) of pathogenic variants (likely pathogenic variants are not included) were distributed in exon 14 of BRCA1 and exon 11 of BRCA2, respectively. The most common pathogenic variants among this Hakka population are c.2635G > T (p.Glu879*) (n = 7) in the BRCA1 gene and c.5164_5165del (p.Ser1722Tyrfs*4) (n = 7) in the BRCA2 gene among the Hakka population. A hotspot mutation in the Chinese population, the BRCA1 c.5470_5477del variant was not found in this Hakka population. The prevalence and spectrum of variants in the BRCA genes in the Hakka patients are different from that in other ethnic groups.

Conclusions

The most common pathogenic variant in this population is c.2635G > T in the BRCA1 gene, and c.5164_5165delAG in the BRCA2 gene in this population. The prevalence and spectrum of variants in the BRCA1 and BRCA2 genes in the Hakka patients from southern China are different from those in other ethnic groups.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09943-0.

Mutational spectrum of BRCA1/2 genes in Moroccan patients with hereditary breast and/or ovarian cancer, and review of BRCA mutations in the MENA region

PURPOSE

Breast cancer (BC) is the most common form of female cancer around the world. BC is mostly sporadic, and rarely hereditary. These hereditary forms are mostly BRCA1- and BRCA2-associated hereditary breast and ovarian cancer syndrome. BRCA1 and BRCA2 genes are large and had some recurrent mutations specific to some populations. Through this work we analyze the most recurrent mutations in Moroccan population and compared them to a large review of other BRCA1/2 spectrum mutations in the MENA region.

METHODS

We report in this work a series of 163 unrelated patients (the largest series of Moroccan patients) with familial breast and/or ovarian cancer, selected among patients referred to our oncogenetic outpatient clinic, from 2006 to 2021. To identify genetic variants in these two genes, different genetic analysis strategies have been carried out, using Sanger Sequencing DNA or Target Panel Sequencing.

RESULTS

Pathogenic variants were identified in 27.6% of patients. The most frequent mutation identified in our patients was the c.1310_1313delAAGA, BRCA2 (33%), and three other mutations seem more frequent in the Moroccan population (33%) of all reported patients: c.798_799delTT, BRCA1; and c.3279delC, BRCA1; and c.7234_7235insG in BRCA2 gene.

CONCLUSION

Through this work, we emphasize the importance of screening for BRCA1 and BRCA2 recurrent mutations in Moroccan patients. Other MENA (MENA: English-language acronym referring to the Middle East and North Africa region) countries had also some recurrent BRCA mutations, which will allow a fast and unexpensive first line genetic analysis and a precise molecular diagnosis. This will allow an adapted follow-up of the patients and a pre-symptomatic diagnosis of their relatives.

Germline Mutational Landscape in Chinese Patients With Advanced Breast Cancer

Background

Genetic testing for breast cancer (BC) patients may shift the paradigm towards more personalized management and treatment strategies. While gene alterations may be ethnic-specific in breast cancer, our understanding of genetic epidemiology of BC remains mainly driven by data from Caucasian populations and further limited to selected handful of genes.

Methods

We collected whole blood samples from 356 BC patients at metastatic first line BC and primary stage IV disease at Beijing Cancer Hospital between Jan. 2013 to Dec. 2019. A comprehensive 600-gene cancer panel was used to detect germline variants in the covered genes with a median 300x sequencing depth. Variants were classified into pathogenic, likely pathogenic, variant of uncertain significance, likely benign and benign groups according to the ACMG/AMP Standards and Guidelines. Pathogenic and likely pathogenic variants were considered as deleterious mutations.

Results

The median age of 356 BC patients was 49 years (range, 21-87 years) at the first diagnosis of BC. Deleterious germline mutations across 48 cancer-related genes were identified in 21.6% (77/356) of the patients. The most prevalent mutations were BRCA1/2 mutations (7.0%), followed by ATM and RAD50 mutations (1.4% each). In addition, patients with family history were more likely to carry BRCA1 mutations (P=0.04). Moreover, patients with triple-negative breast cancer (TNBC) were more likely to harbor BRCA1 mutations than those with HR+ or HER2+ breast cancer (P=0.006). While there was no significant survival difference observed in BRCA1/2 carriers relative to non-carriers, patients with DNA damage repair (DDR) gene mutations (mostly frequently BRCA, ATM, RAD50) had worse disease-free survival (P=0.02).

Conclusions

The most prevalent germline mutations in a large cohort of Chinese patients with advanced BC were BRCA1/2 mutations, followed by ATM and RAD50 mutations. In total, approximately 16.0% (57/356) of patients carry deleterious mutations in DDR pathway. Patients with breast or ovarian cancer family history were more likely to carry BRCA1/2 mutations, and ones with DDR mutations had worse survival. These findings suggest that DDR mutations are prevalent in Chinese BC patients who may potentially benefit from treatment with Poly (ADP-ribose) polymerase inhibitors.

Prevalence of specific and recurrent/founder pathogenic variants in BRCA genes in breast and ovarian cancer in North Africa

Background

Elucidation of specific and recurrent/founder pathogenic variants (PVs) in BRCA (BRCA1 and BRCA2) genes can make the genetic testing, for breast cancer (BC) and/or ovarian cancer (OC), affordable for developing nations.

Methods

To establish the knowledge about BRCA PVs and to determine the prevalence of the specific and recurrent/founder variants in BRCA genes in BC and/or OC women in North Africa, a systematic review was conducted in Morocco, Algeria, and Tunisia.

Results

Search of the databases yielded 25 relevant references, including eleven studies in Morocco, five in Algeria, and nine in Tunisia. Overall, 15 studies investigated both BRCA1 and BRCA2 genes, four studies examined the entire coding region of the BRCA1 gene, and six studies in which the analysis was limited to a few BRCA1 and/or BRCA2 exons. Overall, 76 PVs (44 in BRCA1 and32 in BRCA2) were identified in 196 BC and/or OC patients (129 BRCA1 and 67 BRCA2 carriers). Eighteen of the 76 (23.7%) PVs [10/44 (22.7%) in BRCA1 and 8/32 (25%) in BRCA2] were reported for the first time and considered to be novel PVs. Among those identified as unlikely to be of North African origin, the BRCA1 c.68_69del and BRCA1 c.5266dupC Jewish founder alleles and PVs that have been reported as recurrent/founder variants in European populations (ex: BRCA1 c.181T>G, BRCA1 c1016dupA). The most well characterized PVs are four in BRCA1 gene [c.211dupA (14.7%), c.798_799detTT (14%), c.5266dup (8.5%), c.5309G>T (7.8%), c.3279delC (4.7%)] and one in BRCA2 [c.1310_1313detAAGA (38.9%)]. The c.211dupA and c.5309G>T PVs were identified as specific founder variants in Tunisia and Morocco, accounting for 35.2% (19/54) and 20.4% (10/49) of total established BRCA1 PVs, respectively. c.798_799delTT variant was identified in 14% (18/129) of all BRCA1 North African carriers, suggesting a founder allele. A broad spectrum of recurrent variants including BRCA1 3279delC, BRCA1 c.5266dup and BRCA2 c.1310_1313detAAGA was detected in 42 patients. BRCA1 founder variants explain around 36.4% (47/129) of BC and outnumber BRCA2 founder variants by a ratio of ≈3:1.

Conclusions

Testing BC and/or OC patients for the panel of specific and recurrent/founder PVs might be the most cost-effective molecular diagnosis strategy.

Population Screening in Health Systems

Applications of genomics to population screening are expanding in the United States and internationally. Many of these programs are being implemented in the context of healthcare systems, mostly in a clinical research setting, but there are some emerging examples of clinical models. This review examines these genomic population screening programs to identify common features and differences in screened conditions, genomic technology employed, approach to results disclosure, health outcomes, financial models, and sustainability. The diversity of approaches provides opportunities to learn and better understand the optimal approach to implementation based on the contextual setting. Expected final online publication date for the Annual Review of Genomics and Human Genetics, Volume 23 is October 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Assessing frequency and clinical outcomes of BRCA mutated ovarian cancer in Saudi women

PURPOSE

BRCA gene mutations (BRCAm) have an impact on patients' characteristics and clinical outcomes of ovarian cancer (OC). The frequency and patterns of BRCAm vary among countries and ethnicities. There are limited data from Saudi Arabia (SA); thus, this study aims to determine the frequency, pattern, and impact on patient characteristics and outcomes of BRCAm OC compared to wild-type BRCA (BRCAw) in Saudi women.

METHODS

This retrospective study evaluated women diagnosed with non-mucinous OC, fallopian tube, or peritoneal carcinoma who had BRCA status tested in an accredited lab between January 2016 and December 2017. The associations between various parameters and BRCAm were estimated using logistic regression. Statistical analysis performed with SPSS (Version 27).

RESULT

Sixty-one women with a median age of 52 at diagnosis were analyzed. Germline BRCA mutations were found in 41% of cases (25/61). The most common deleterious germline BRCA1 mutation was c.1140dupG (39%). Most women (72%) had no family history of cancers and 82% had advanced stage. Regardless of BRCA mutations, an optimal overall response rate (ORR) to first-line treatment has been achieved although most cases relapsed (84%) and the majority were platinum-sensitive relapse (85%). Higher ORR to subsequent lines and better survival were obtained in women with BRCA-mutation.

CONCLUSION

The prevalence of BRCAm of OC was higher in Saudi women compared to regional and most of the international figures. The better clinical outcomes of BRCAm women agreed with the reported evidence. Further studies on BRCA mutations of OC and genetic counseling are highly recommended.

TRIAL REGISTRATION

Trial approved by the Institutional Review Board of King Faisal Specialist Hospital and Research Center (RAC # 2171137) and conducted at King Faisal Specialist Hospital and Research Center, PO Box 3354, Riyadh 11,211, Saudi Arabia.

Advances and challenges in cancer treatment and nutraceutical prevention: the possible role of dietary phenols in BRCA regulation

Over the years, the attention towards the role of phytochemicals in dietary natural products in reducing the risk of developing cancer is rising. Cancer is the second primary cause of mortality worldwide. The current therapeutic options for cancer treatment are surgical excision, immunotherapy, chemotherapy, and radiotherapy. Unfortunately, in case of metastases or chemoresistance, the treatment options become very limited. Despite the advances in medical and pharmaceutical sciences, the impact of available treatments on survival is not satisfactory. Recently, natural products are a great deal of interest as potential anti-cancer agents. Among them, phenolic compounds have gained a great deal of interest, thanks to their anti-cancer activity. The present review focuses on the suppression of cancer by targeting BRCA gene expression using dietary polyphenols, as well as the clinical aspects of polyphenolic agents in cancer therapy. They regulate specific key processes involved in cancer progression and modulate the expression of oncogenic proteins, like p27, p21, and p53, which may lead to apoptosis, cell cycle arrest, inhibition of cell proliferation, and, consequently, cancer suppression. Thus, one of the mechanisms underlying the anti-cancer activity of phenolics involves the regulation of tumor suppressor genes. Among them, the BRCA genes, with the two forms (BRCA-1 and BRCA-2), play a pivotal role in cancer protection and prevention. BRCA germline mutations are associated with an increased risk of developing several types of cancers, including ovarian, breast, and prostate cancers. BRCA genes also play a key role in the sensitivity and response of cancer cells to specific pharmacological treatments. As the importance of BRCA-1 and BRCA-2 in reducing cancer invasiveness, repairing DNA damages, oncosoppression, and cell cycle checkpoint, their regulation by natural molecules has been examined.

Melittin, a honeybee venom derived peptide for the treatment of chemotherapy-induced peripheral neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is the most prevalent neurological complication of cancer treatment which involves sensory and motor nerve dysfunction. Severe CIPN has been reported in around 5% of patients treated with single and up to 38% of patients treated with multiple chemotherapeutic agents. Present medications available for CIPN are the use of opioids, nonsteroidal anti-inflammatory agents, and tricyclic antidepressants, which are only marginally effective in treating neuropathic symptoms. In reality, symptom reappears after these drugs are discontinued. The pathogenesis of CIPN has not been sufficiently recognized and methods for the prevention and treatment of CIPN remain vulnerable to therapeutic problems. It has witnessed that the present medicines available for the disease offer only symptomatic relief for the short term and have severe adverse side effects. There is no standard treatment protocol for preventing, reducing, and treating CIPN. Therefore, there is a need to develop curative therapy that can be used to treat this complication. Melittin is the main pharmacological active constituent of honeybee venom and has therapeutic values including in chemotherapeutic-induced peripheral neuropathy. It has been shown that melittin and whole honey bee venom are effective in treating paclitaxel and oxaliplatin-induced peripheral neuropathy. The use of melittin against peripheral neuropathy caused by chemotherapy has been limited despite having strong therapeutic efficacy against the disease. Melittin mediated haemolysis is the key reason to restrict its use. In our study, it is found that α-Crystallin (an eye lens protein) is capable of inhibiting melittin-induced haemolysis which gives hope of using an appropriate combination of melittin and α-Crystallin in the treatment of CIPN. The review summarizes the efforts made by different research groups to address the concern with melittin in the treatment of chemotherapeutic-induced neuropathy. It also focuses on the possible approaches to overcome melittin-induced haemolysis.

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.

Epidemiology of cancer in Saudi Arabia thru 2010-2019: a systematic review with constrained meta-analysis

Background

Cancer is emerging as a major global health-care system challenge with a growing burden worldwide. Due to the inconsistent cancer registry system in Saudi Arabia, the epidemiology of cancer is still dispersed in the country. Consequently, this review aimed to assemble the epidemiological metrics of cancer in Saudi Arabia in light of the available published data during the period from (2010–2019).

Methods

Published literature from Saudi Arabia relating to cancer incidence, prevalence, risk factors, and other epidemiological metrics were accessed through electronic search in Medline/PubMed, Cochrane, Scopus, Web of Knowledge, Google Scholar, and public database that meet the inclusion criteria. Relevant keywords were used during the electronic search about different types of cancers in Saudi Arabia. No filters were used during the electronic searches. Data were pooled and odds ratios (ORs) and 95% confidence interval (95%CI) were calculated. A random-effects meta-analysis was performed to assess the well-determined risk factors associated with different types of cancers.

Results

The most common cancers in Saudi Arabia are breast, colorectal, prostate, brain, lymphoma, kidney and thyroid outnumbering respectively. Their prevalence rates and OR (95%CI) as follow: breast cancer 53% and 0.93 (0.84–1.00); colon-rectal cancer (CRC) 50.9% and 1.2 (0.81–1.77); prostate cancer 42.6% and 3.2 (0.88–31.11); brain/Central Nervous System cancer 9.6% and 2.3 (0.01–4.2); Hodgkin and non-Hodgkin's lymphoma 9.2% and 3.02 (1.48–6.17); kidney cancer 4.6% and 2.05 (1.61–2.61), and thyroid cancer 12.9% and 6.77 (2.34–19.53).

Conclusion

Within the diverse cancers reported from Saudi Arabia, the epidemiology of some cancers magnitude 3-fold in the latest years. This increase might be attributed to the changing in the Saudi population lifestyle (adopting western model), lack of cancer awareness, lack of screening & early detection programs, social barriers toward cancer investigations. Obesity, genetics, sedentary lifestyle, tobacco use, viral infection, and iodine & Vit-D deficiency represent the apparent cancer risk factors in Saudi Arabia.

Contribution of BRCA1 and BRCA2 germline mutations to early onset breast cancer: a series from north of Morocco

BACKGROUND

To date, the contribution of BRCA1/2 mutations in Moroccan early onset breast cancer patients remains unknown. Here we assess these genetic alterations for the first time in a cohort from North of Morocco.

METHODS

Thirty-three patients diagnosed with breast cancer at the age of ≤40 years were recruited irrespective of breast and/or ovarian cancer family history. Coding regions and intron-exon boundaries of BRCA1 and BRCA2 genes were sequenced from peripheral blood DNA using Ion Proton (Thermo Fisher Scientific) next generation sequencing platform.

RESULTS

Overall, five BRCA germline mutations were identified (15.1%). The frequency of mutations among patients with family history of breast cancer was 16.7%. Three mutations were found in BRCA1 (9%) and two within the BRCA2 gene (6%). These are three frameshift mutations (c.798_799del, c.2125_2126insA, c.5116_5119delAATA), one missense (c.116G > A) and one nonsense mutation (c.289G > T). The mutation c.5116_5119delAATA has a founder effect in North Africa. Moreover, one variant of unknown significance was identified in BRCA2 (c.4090A > G). Most BRCA mutations carriers (80%) had no family history of breast cancer.

CONCLUSION

Our data do not support the hypothesis that BRCA mutations alone explain the higher frequency of breast cancer in Moroccan young women. The young age (≤40 years) for breast cancer diagnosis seems to be strongly predictive of BRCA mutation status in Moroccan patients. These results will help in decision making with regard to genetic counseling and testing in the national scale.

Clinicopathological characteristics of gene-positive breast cancer in the United Arab Emirates

Introduction

Breast cancer is the most prevalent cancer in the United Arab Emirates (UAE). This is the first study to provide data on predisposition of breast cancer susceptibility genes with associated clinical and pathological aspects in the UAE.

Material & methods

A retrospective chart review for breast cancer patients undergoing genetic testing from 2016 to 2018. According to National Comprehensive Cancer Network (NCCN) guidelines genetic testing was offered. The analyzed data included; age, ethnicity, family cancer history, pathogenic variant, histopathology, stage, molecular subtype and proliferation.

Results

309 patients underwent genetic testing with a positive result in 130 patients (11.9%) over a period of 36 months. In 34.6% pathogenic and likely pathogenic variants were identified. BRCA2 was the most common gene identified. The mean age was 42.9 years (±9.01). Positive family history was identified in 66 patients (50.7%). Majority had stage 1 or 2 disease (66.2%), invasive ductal carcinoma (81.5%) and hormone receptor positive cancer (45.3%).

Conclusions

This is the first study in the UAE to describe the clinical and pathological characteristics of hereditary breast cancer in a mixed ethnic group with dominant Arabic population. Further genetic studies will be required in the UAE population, as the prevalence of breast cancer continues to rise.

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First study about breast cancer genetics in the United Arab Emirates with a mixed ethnic population.

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BRCA2 is the most common mutation detected.

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Most hereditary breast cancers with a dominant Arabic ethnic group is diagnosed at a lower stage.

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Most hereditary breast cancers diagnosed a decade earlier compared to western population.

Familial/inherited cancer syndrome: a focus on the highly consanguineous Arab population

The study of hereditary cancer, which accounts for ~10% of cancer cases worldwide is an important subfield of oncology. Our understanding of hereditary cancers has greatly advanced with recent advances in sequencing technology, but as with any genetic trait, gene frequencies of cancer-associated mutations vary across populations, and most studies that have located hereditary cancer genes have been conducted on European or Asian populations. There is an urgent need to trace hereditary cancer genes across the Arab world. Hereditary disease is particularly prevalent among members of consanguineous populations, and consanguineous marriages are particularly common in the Arab world. There are also cultural and educational idiosyncrasies that differentiate Arab populations from other more thoroughly studied groups with respect to cancer awareness and treatment. Therefore, a review of the literature on hereditary cancers in this understudied population was undertaken. We report that BRCA mutations are not as prevalent among Arab breast cancer patients as they are among other ethnic groups, and therefore, other genes may play a more important role. A wide variety of germline inherited mutations that are associated with cancer are discussed, with particular attention to breast, ovarian, colorectal, prostate, and brain cancers. Finally, we describe the state of the profession of familial cancer genetic counselling in the Arab world, and the clinics and societies dedicated to its advances. We describe the complexities of genetic counselling that are specific to the Arab world. Understanding hereditary cancer is heavily dependent on understanding population-specific variations in cancer-associated gene frequencies.

Frequency of germline mutations in BRCA1 and BRCA2 in ovarian cancer patients and their effect on treatment outcome

Aim of work

Reporting the incidence and the variants of BRCA1/2 mutations in ovarian cancer patients exploring their effects on the treatment outcomes.

Patients and methods

In total, 104 patients with epithelial ovarian cancer were prospectively recruited to the study. Analysis consisted of the sequencing of all the translated exons and immediately adjacent intronic regions of the BRCA1/2 genes. Responses to multiple lines of chemotherapy were assessed, as well as the effect of BRCA gene mutations on progression-free survival (PFS) and overall survival (OS).

Results

Pathogenic BRCA1/2 mutations were found in 21.15% of the patients. BRCA1 mutations represented 68.2% of the total mutations. Two novel BRCA1 mutations were identified. Age at diagnosis was a strong predictor of the presence of a pathogenic BRCA1/2 mutation. Patients with a family history of cancer had a higher incidence of BRCA mutations (P=0.005). As high as 72% of the patients with BRCA mutations were diagnosed at advanced stage. High-grade serous tumors have a higher incidence of pathogenic mutation (P=0.07). Response to neoadjuvant chemotherapy was high (93.9%). All patients underwent surgery which was optimal in 73.1% of the patients. As high as 85.6% of the patients received adjuvant chemotherapy. Relapse rate was 45.2%. Visceral metastasis was more often in BRCA carriers (P=0.01). Patients carrying pathogenic BRCA1/2 mutations had a longer median PFS of 42.43 months (95% CI 32.04–52.83) compared to 22.24 months (95% CI 14.83–29.58) for non-carriers (P=0.08). OS was 64.32 months (95% CI 38.09–90.06) for BRCA mutation patients versus 56.63 months (95% CI 50.05–63.21) (P=0.04) for non-carriers. In multivariate analysis, early stage at diagnosis and optimal debulking were the only independent predictors of better PFS and OS.

Conclusion

We documented a number of pathogenic BRCA1 and 2 mutations in this patients cohort; two novel mutations were detected. BRCA status seemed to affect survival in ovarian cancer patients.

Prevalence of BRCA mutations among hereditary breast and/or ovarian cancer patients in Arab countries: systematic review and meta-analysis

Background

To systematically assess the prevalence of BRCA1 and BRCA2 gene mutations in women with Hereditary Breast and/or Ovarian Cancer (HBOC) in Arab countries and to describe the variability in the BRCA gene mutations in different regions of the Arab world.

Methods

Observational studies reporting prevalence of BRCA mutations from 22 Arab countries were systematically searched in databases including PUBMED, EMBASE, Web of Science, and Google Scholar. Two reviewers independently screened the studies and extracted data and assessed the risk of bias. Hoy’s risk of Bias tool was used to assess the biases in individual studies. Due to substantial heterogeneity, pooled weighted estimates were calculated using Quality Effect Models (QEM) that adjust for bias, while the Random Effect Models (REM) estimates served as the sensitivity estimates.

Results

Fourteen studies reporting prevalence of BRCA were included. The pooled estimate of BRCA among HBOC was 20% (95% CI: 7–36%). Subgroup analysis including only those with low risk of bias provided an estimate of 11% (95% CI: 1–27%). Levant region had higher prevalence 28% (95% CI: 11–49%) compared to Arabian Gulf region and North Africa but differences are not statistically significant, when tested using Z-test for proportions.

Conclusion

Given the pooled estimates vary widely with substantial heterogeneity, larger, well-designed studies are warranted to better understand the frequency and the impact of BRCA gene mutations among Arab women.

Trial registration

International Prospective Register of Systematic Reviews (PROSPERO) registration number: CRD42018095905.

BRCA mutation screening and patterns among high-risk Lebanese subjects

Background

Previous studies have suggested that the prevalence of BRCA1 and 2 mutations in the Lebanese population is low despite the observation that the median age of breast cancer diagnosis is significantly lower than European and North American populations. We aimed at reviewing the rates and patterns of BRCA1/2 mutations found in individuals referred to the medical genetics unit at the American University of Beirut. We also evaluated the performance of clinical prediction tools.

Methods

We retrospectively reviewed the cases of all individuals undergoing BRCA mutation testing from April 2011 to May 2016. To put our findings in to context, we conducted a literature review of the most recently published data from the region.

Results

Two-hundred eighty one individuals were referred for testing. The prevalence of mutated BRCA1 or 2 genes were 6 and 1.4% respectively. Three mutations accounted for 54% of the pathogenic mutations found. The BRCA1 c.131G > T mutation was found among 5/17 (29%) unrelated subjects with BRCA1 mutation and is unique to the Lebanese and Palestinian populations. For patients tested between 2014 and 2016, all patients positive for mutations fit the NCCN guidelines for BRCA mutation screening. The Manchester Score failed to predict pathogenic mutations.

Conclusion

The BRCA1 c.131G > T mutation can be considered a founder mutation in the Lebanese population detected among 5/17 (29%) of individuals diagnosed with a mutation in BRCA1 and among 7/269 families in this cohort. On review of recently published data regarding the landscape of BRCA mutations in the Middle East and North Africa, each region appears to have a unique spectrum of mutations.

Prevalence of BRCA1 and BRCA2 pathogenic and likely pathogenic variants in non-selected ovarian carcinoma patients in Brazil

Background

BRCA1/2 pathogenic (P) and likely pathogenic (LP) germline variants are frequent among patients with ovarian carcinoma. However, these variants have not been extensively characterized in patients with ovarian cancer in Brazil.

Methods

In this retrospective study we evaluated clinical characteristics and BRCA1/2 genetic test results from patients with ovarian carcinoma who underwent genetic counseling at A.C.Camargo Cancer Center (Brazil) between 2015 and 2017 and had performed germline genetic testing of BRCA1/2 genes.

Results

Among 158 patients, 33 P and LP variants and were found (20.8%), 27 in BRCA1 and six in BRCA2, and six variants of unknown clinical significance (VUS). Thirteen percent of the patients did not have Multiplex Ligation-dependent Probe Amplification (MLPA) results. Three P variants in BRCA1 were found in more than one patient: c.5266dupC (p.Gln1756Profs*74), c.3331_3334delCAAG (p.Gln1111Asnfs5*), and c.211A > G (p.Arg71Gly). One LP variant in BRCA1 had not been previously described, c.4153_4154delCT (p.Leu1385Ilefs*5). Patients with previous diagnosis of breast cancer were carriers of P or LP variant in 8 of 12 cases (66.7%), and patients with a family history of ovarian or breast cancer in first- or second-degree relatives were carriers of P or LP variant in 26.7% of cases compared to 16.9% for patients without family history (p = 0.166).

Conclusion

Prevalence of BRCA1/2 germline P and LP variants is slightly higher than previously described by the largest occidental studies, with a high prevalence of variant c.5266dupC (p.Gln1756Profs*74) in BRCA1 observed. Moreover, we identified a new LP variant.

Risk-reducing bilateral salpingo-oophorectomy in women with BRCA1 or BRCA2 mutations

BACKGROUND

The presence of deleterious mutations in breast cancer 1 gene (BRCA1) or breast cancer 2 gene (BRCA2) significantly increases the risk of developing some cancers, such as breast and high-grade serous cancer (HGSC) of ovarian, tubal and peritoneal origin. Risk-reducing salpingo-oophorectomy (RRSO) is usually recommended to BRCA1 or BRCA2 carriers after completion of childbearing. Despite prior systematic reviews and meta-analyses on the role of RRSO in reducing the mortality and incidence of breast, HGSC and other cancers, RRSO is still an area of debate and it is unclear whether RRSO differs in effectiveness by type of mutation carried.

OBJECTIVES

To assess the benefits and harms of RRSO in women with BRCA1 or BRCA2 mutations.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 7) in The Cochrane Library, MEDLINE Ovid, Embase Ovid and trial registries, with no language restrictions up to July 2017. We handsearched abstracts of scientific meetings and other relevant publications.

SELECTION CRITERIA

We included non-randomised trials (NRS), prospective and retrospective cohort studies, and case series that used statistical adjustment for baseline case mix using multivariable analyses comparing RRSO versus no RRSO in women without a previous or coexisting breast, ovarian or fallopian tube malignancy, in women with or without hysterectomy, and in women with a risk-reducing mastectomy (RRM) before, with or after RRSO.

DATA COLLECTION AND ANALYSIS

We extracted data and performed meta-analyses of hazard ratios (HR) for time-to-event variables and risk ratios (RR) for dichotomous outcomes, with 95% confidence intervals (CI). To assess bias in the studies, we used the ROBINS-I 'Risk of bias' assessment tool. We quantified inconsistency between studies by estimating the I² statistic. We used random-effects models to calculate pooled effect estimates.

MAIN RESULTS

We included 10 cohort studies, comprising 8087 participants (2936 (36%) surgical participants and 5151 (64%) control participants who were BRCA1 or BRCA2 mutation carriers. All the studies compared RRSO with or without RRM versus no RRSO (surveillance). The certainty of evidence by GRADE assessment was very low due to serious risk of bias. Nine studies, including 7927 women, were included in the meta-analyses. The median follow-up period ranged from 0.5 to 27.4 years.

MAIN OUTCOMES

overall survival was longer with RRSO compared with no RRSO (HR 0.32, 95% CI 0.19 to 0.54; P < 0.001; 3 studies, 2548 women; very low-certainty evidence). HGSC cancer mortality (HR 0.06, 95% CI 0.02 to 0.17; I² = 69%; P < 0.0001; 3 studies, 2534 women; very low-certainty evidence) and breast cancer mortality (HR 0.58, 95% CI 0.39 to 0.88; I² = 65%; P = 0.009; 7 studies, 7198 women; very low-certainty evidence) were lower with RRSO compared with no RRSO. None of the studies reported bone fracture incidence. There was a difference in favour of RRSO compared with no RRSO in terms of ovarian cancer risk perception quality of life (MD 15.40, 95% CI 8.76 to 22.04; P < 0.00001; 1 study; very low-certainty evidence). None of the studies reported adverse events.Subgroup analyses for main outcomes: meta-analysis showed an increase in overall survival among women who had RRSO versus women without RRSO who were BRCA1 mutation carriers (HR 0.30, 95% CI 0.17 to 0.52; P < 0001; I² = 23%; 3 studies; very low-certainty evidence) and BRCA2 mutation carriers (HR 0.44, 95% CI 0.23 to 0.85; P = 0.01; I² = 0%; 2 studies; very low-certainty evidence). The meta-analysis showed a decrease in HGSC cancer mortality among women with RRSO versus no RRSO who were BRCA1 mutation carriers (HR 0.10, 95% CI 0.02 to 0.41; I² = 54%; P = 0.001; 2 studies; very low-certainty evidence), but uncertain for BRCA2 mutation carriers due to low frequency of HGSC cancer deaths in BRCA2 mutation carriers. There was a decrease in breast cancer mortality among women with RRSO versus no RRSO who were BRCA1 mutation carriers (HR 0.45, 95% CI 0.30 to 0.67; I² = 0%; P < 0.0001; 4 studies; very low-certainty evidence), but not for BRCA2 mutation carriers (HR 0.88, 95% CI 0.42 to 1.87; I² = 63%; P = 0.75; 3 studies; very low-certainty evidence). One study showed a difference in favour of RRSO versus no RRSO in improving quality of life for ovarian cancer risk perception in women who were BRCA1 mutation carriers (MD 10.70, 95% CI 2.45 to 18.95; P = 0.01; 98 women; very low-certainty evidence) and BRCA2 mutation carriers (MD 13.00, 95% CI 3.59 to 22.41; P = 0.007; very low-certainty evidence). Data from one study showed a difference in favour of RRSO and RRM versus no RRSO in increasing overall survival (HR 0.14, 95% CI 0.02 to 0.98; P = 0.0001; I² = 0%; low-certainty evidence), but no difference for breast cancer mortality (HR 0.78, 95% CI 0.51 to 1.19; P = 0.25; very low-certainty evidence). The risk estimates for breast cancer mortality according to age at RRSO (50 years of age or less versus more than 50 years) was not protective and did not differ for BRCA1 (HR 0.85, 95% CI 0.64 to 1.11; I² = 16%; P = 0.23; very low-certainty evidence) and BRCA2 carriers (HR 0.88, 95% CI 0.42 to 1.87; I² = 63%; P = 0.75; very low-certainty evidence).

AUTHORS' CONCLUSIONS

There is very low-certainty evidence that RRSO may increase overall survival and lower HGSC and breast cancer mortality for BRCA1 and BRCA2 carriers. Very low-certainty evidence suggests that RRSO reduces the risk of death from HGSC and breast cancer in women with BRCA1 mutations. Evidence for the effect of RRSO on HGSC and breast cancer in BRCA2 carriers was very uncertain due to low numbers. These results should be interpreted with caution due to questionable study designs, risk of bias profiles, and very low-certainty evidence. We cannot draw any conclusions regarding bone fracture incidence, quality of life, or severe adverse events for RRSO, or for effects of RRSO based on type and age at risk-reducing surgery. Further research on these outcomes is warranted to explore differential effects for BRCA1 or BRCA2 mutations.