Identification of Eleven Novel BRCA Mutations in Tunisia: Impact on the Clinical Management of BRCA Related Cancers

Author(s):  
Yosr Hamdi ◽  
Najah Mighri ◽  
Maroua Boujemaa ◽  
Nesrine Mejri ◽  
Sonia Ben Nasr ◽  
...  

Abstract Background Breast cancer is the world's most common cancer among women. It is becoming an increasingly urgent problem in low- and middle-income countries (LMICs) where a large fraction of women is diagnosed with advanced-stage disease and have no access to treatment or basic palliative care. About 5-10% of all breast cancers can be attributed to hereditary genetic components and up to 25% of familial cases are due to mutations in BRCA1/2 genes. Since their discovery in 1994 and 1995, as few as 18 mutations have been identified in BRCA genes in the Tunisian population. The aim of this study is to identify additional BRCA mutations, to estimate their contribution to the hereditary breast and ovarian cancers in Tunisia and to investigate the clinicopathological signatures associated with BRCA mutations. Methods A total of 354 patients diagnosed with breast and ovarian cancers, including 5 male breast cancer cases, have been investigated for BRCA1/2 mutations using traditional and/or next generation sequencing technologies. Clinicopathological signatures associated with BRCA mutations have been also investigated. Results 16 distinct mutations were detected: 10 in BRCA1 and 6 in BRCA2, of which 11 are described for the first time in Tunisia including 3 variations that have not been reported previously in public databases namely BRCA1_c.915T>A; BRCA2_c.-227-?_7805+? and BRCA2_c.249delG. Early age at onset, family history of ovarian cancer and high tumor grade were significantly associated with BRCA status. BRCA1 carriers were more likely to be triple negative breast cancer compared to BRCA2 carriers. A relatively high frequency of contralateral breast cancer and ovarian cancer occurrence was observed among BRCA carriers and was more frequent in patients carrying BRCA1 mutations. Conclusion Our study provides new insights into breast and ovarian cancer genetic landscape in the under-represented North African populations. The prevalence assessment of novel and recurrent BRCA1/2 pathogenic mutations will enhance the use of personalized treatment and precise screening strategies by both affected and unaffected North African cancer cases.

2021 ◽  
Vol 11 ◽  
Author(s):  
Yosr Hamdi ◽  
Najah Mighri ◽  
Maroua Boujemaa ◽  
Nesrine Mejri ◽  
Sonia Ben Nasr ◽  
...  

BackgroundBreast cancer is the world’s most common cancer among women. It is becoming an increasingly urgent problem in low- and middle-income countries (LMICs) where a large fraction of women is diagnosed with advanced-stage disease and have no access to treatment or basic palliative care. About 5-10% of all breast cancers can be attributed to hereditary genetic components and up to 25% of familial cases are due to mutations in BRCA1/2 genes. Since their discovery in 1994 and 1995, as few as 18 mutations have been identified in BRCA genes in the Tunisian population. The aim of this study is to identify additional BRCA mutations, to estimate their contribution to the hereditary breast and ovarian cancers in Tunisia and to investigate the clinicopathological signatures associated with BRCA mutations.MethodsA total of 354 patients diagnosed with breast and ovarian cancers, including 5 male breast cancer cases, have been investigated for BRCA1/2 mutations using traditional and/or next generation sequencing technologies. Clinicopathological signatures associated with BRCA mutations have also been investigated.ResultsIn the current study, 16 distinct mutations were detected: 10 in BRCA1 and 6 in BRCA2, of which 11 are described for the first time in Tunisia including 3 variations that have not been reported previously in public databases namely BRCA1_c.915T>A; BRCA2_c.-227-?_7805+? and BRCA2_c.249delG. Early age at onset, family history of ovarian cancer and high tumor grade were significantly associated with BRCA status. BRCA1 carriers were more likely to be triple negative breast cancer compared to BRCA2 carriers. A relatively high frequency of contralateral breast cancer and ovarian cancer occurrence was observed among BRCA carriers and was more frequent in patients carrying BRCA1 mutations.ConclusionOur study provides new insights into breast and ovarian cancer genetic landscape in the under-represented North African populations. The prevalence assessment of novel and recurrent BRCA1/2 pathogenic mutations will enhance the use of personalized treatment and precise screening strategies by both affected and unaffected North African cancer cases.


2021 ◽  
pp. 849-861
Author(s):  
Sudeep Gupta ◽  
Senthil Rajappa ◽  
Suresh Advani ◽  
Amit Agarwal ◽  
Shyam Aggarwal ◽  
...  

PURPOSE There are deficient data on prevalence of germline mutations in breast cancer susceptibility genes 1 and 2 ( BRCA1/ BRCA2) in Indian patients with ovarian cancer who are not selected by clinical features. METHODS This prospective, cross-sectional, noninterventional study in nine Indian centers included patients with newly diagnosed or relapsed epithelial ovarian, primary peritoneal, or fallopian tube cancer. The primary objective was to assess the prevalence of BRCA1/ BRCA2 mutations, and the secondary objective was to correlate BRCA1/ BRCA2 status with clinicopathologic characteristics. Mutation testing was performed by a standard next-generation sequencing assay. RESULTS Between March 2018 and December 2018, 239 patients with a median age of 53.0 (range, 23.0-86.0 years) years were included, of whom 203 (84.9%) had newly diagnosed disease, 36 (15.1%) had family history of ovarian or breast cancer, and 159 (66.5%) had serous subtype of epithelial ovarian cancer. Germline pathogenic or likely pathogenic mutations in BRCA1 and BRCA2 were detected in 37 (15.5%; 95% CI, 11.1 to 20.7) and 14 (5.9%; 95% CI, 3.2 to 9.6) patients, respectively, whereas variants of uncertain significance in these genes were seen in four (1.7%; 95% CI, 0.5 to 4.2) and six (2.5%; 95% CI, 0.9 to 5.4) patients, respectively. The prevalence of pathogenic or likely pathogenic BRCA mutations in patients with serous versus nonserous tumors, with versus without relevant family history, and ≤ 50 years versus > 50 years, were 40 of 159 (25.2%; 95% CI, 18.6 to 32.6) versus 11 of 80 (13.8%; 95% CI, 7.1 to 23.3; P = .0636), 20 of 36 (55.6%; 95% CI, 38.1 to 72.1) versus 41 of 203 (20.2%; 95% CI, 14.9 to 26.4; P < .0001), and 20 of 90 (22.2%; 95% CI, 14.1 to 32.2) versus 31 of 149 (20.8%; 95% CI, 14.6 to 28.2; P = .7956), respectively. CONCLUSION There is a high prevalence of pathogenic or likely pathogenic germline BRCA mutations in Indian patients with ovarian cancer.


2013 ◽  
Vol 31 (2) ◽  
pp. 210-216 ◽  
Author(s):  
Jeffrey N. Weitzel ◽  
Jessica Clague ◽  
Arelis Martir-Negron ◽  
Raquel Ogaz ◽  
Josef Herzog ◽  
...  

PurposeTo determine the prevalence and type of BRCA1 and BRCA2 (BRCA) mutations among Hispanics in the Southwestern United States and their potential impact on genetic cancer risk assessment (GCRA).Patients and MethodsHispanics (n = 746) with a personal or family history of breast and/or ovarian cancer were enrolled in an institutional review board–approved registry and received GCRA and BRCA testing within a consortium of 14 clinics. Population-based Hispanic breast cancer cases (n = 492) enrolled in the Northern California Breast Cancer Family Registry, negative by sequencing for BRCA mutations, were analyzed for the presence of the BRCA1 ex9-12del large rearrangement.ResultsDeleterious BRCA mutations were detected in 189 (25%) of 746 familial clinic patients (124 BRCA1, 65 BRCA2); 21 (11%) of 189 were large rearrangement mutations, of which 62% (13 of 21) were BRCA1 ex9-12del. Nine recurrent mutations accounted for 53% of the total. Among these, BRCA1 ex9-12del seems to be a Mexican founder mutation and represents 10% to 12% of all BRCA1 mutations in clinic- and population-based cohorts in the United States.ConclusionBRCA mutations were prevalent in the largest study of Hispanic breast and/or ovarian cancer families in the United States to date, and a significant proportion were large rearrangement mutations. The high frequency of large rearrangement mutations warrants screening in every case. We document the first Mexican founder mutation (BRCA1 ex9-12del), which, along with other recurrent mutations, suggests the potential for a cost-effective panel approach to ancestry-informed GCRA.


2007 ◽  
Vol 25 (15) ◽  
pp. 2027-2034 ◽  
Author(s):  
Patrícia M. Machado ◽  
Rita D. Brandão ◽  
Branca M. Cavaco ◽  
Joana Eugénio ◽  
Sandra Bento ◽  
...  

Purpose BRCA2 rearrangements are rare genetic events. A large BRCA2 genomic insertion was recurrently observed in our participants, and we sought to characterize it at the molecular and phenotypic level. Patients and Methods We studied 210 high-risk breast/ovarian cancer families. Fifty-three probands were fully screened for BRCA1/2 mutations, and three of 53 had a large insertion in exon 3 of BRCA2. This finding was analyzed by polymerase chain reaction (PCR), reverse transcriptase PCR (RT-PCR), and sequencing. An additional 157 consecutive families were screened for this mutation by a three-step PCR method. Phenotype and haplotype analysis was also performed. Results Sixteen BRCA mutations were observed in 19 of 53 patients (36% detection rate). A recurrent Alu motif insertion in position c.156_157 was observed after sequencing of an abnormal fragment obtained after the amplification of BRCA2 exon 3. RT-PCR revealed exon 3 skipping. Screening of this rearrangement identified 14 additional families (out of 157). In total, 17 (8%) of 210 high-risk families ascertained in our clinic were positive for this mutation. Segregation of a common haplotype (from D13S260 to D13S1695) confirmed a common origin, estimated to have occurred 2,400 to 2,600 years ago. The following four cancer phenotypes were observed in the 17 positive families: female breast (n = 9), male breast (n = 4), breast/ovarian (n = 2), and heterogeneous (n = 2). Male breast cancer was more frequently observed in c.156_157insAlu–positive families compared with negative families (23% v 12%, respectively), and 33% of all male breast cancer families with an identified BRCA mutation were c.156_157insAlu positive. Conclusion c.156_157insAlu is a founder mutation of Portuguese origin and is the most frequent BRCA2 rearrangement described to date.


2019 ◽  
Vol 3 (2) ◽  
Author(s):  
Shawn Yost ◽  
Elise Ruark ◽  
Ludmil B Alexandrov ◽  
Nazneen Rahman

Abstract Background It is often assumed any cancer in a germline BRCA1 or BRCA2 (collectively termed BRCA) mutation carrier was caused by that mutation. It is also often assumed the occurrence of breast or ovarian cancer in an individual with a variant of uncertain significance (VUS) suggests the VUS is pathogenic. These assumptions have profound management implications for cancer patients and healthy individuals. Methods We compared the frequency of BRCA mutations, allele loss, and Signature 3 in 7632 individuals with 28 cancers and 1000 population controls. Because only increased frequency was the focus of the study, all statistical tests were one-sided. Results Individuals with breast or ovarian cancer had increased germline BRCA pathogenic mutation frequencies compared to controls (P = 1.0x10−10 and P = 1.4x10−34, respectively). There was no increase in other cancer types. Wild-type allele loss and Signature 3 were statistically significantly higher in breast and ovarian cancers with BRCA mutations compared with other cancers with BRCA mutations (P = 5.1x10−10 and P = 3.7x10−9) and cancers without BRCA mutations (P = 2.8x10−53 and P = 1.0x10−134). There was no difference between non-breast and non-ovarian cancers with BRCA mutations and cancers without BRCA mutations. Allele loss and Signature 3 were statistically significantly higher in breast and ovarian cancers in individuals with BRCA pathogenic mutations compared to those with VUS (P = 3.8x10−17 and P = 1.6x10−8) or benign variants (P = 1.2x10−28 and P = 2.2x10−10). There was no difference between individuals with BRCA VUS and those with benign variants. Conclusions These data show that non-breast and non-ovarian cancers in individuals with germline BRCA pathogenic mutations are often not causally related to the mutation and that BRCA VUS are highly unlikely to be pathogenic. These results should reduce inappropriate management of germline BRCA information.


2013 ◽  
Vol 31 (6) ◽  
pp. 738-743 ◽  
Author(s):  
Sara J. Schonfeld ◽  
Amy Berrington de Gonzalez ◽  
Kala Visvanathan ◽  
Ruth M. Pfeiffer ◽  
William F. Anderson

Purpose Although ovarian cancer incidence rates have declined in the United States, less is known of ovarian cancer trends among survivors of breast cancer. Therefore, we examined second primary ovarian cancers after first primary breast cancer. Methods Data were obtained from the Surveillance, Epidemiology, and End Results program (1973 to 2008). Standardized incidence ratios (SIRs) were calculated as the observed numbers of ovarian cancers among survivors of breast cancer compared with the expected numbers in the general population. Absolute rates were measured as the incidence rates for second primary ovarian cancer by year of diagnosis of the first primary breast cancer adjusted for age of breast cancer diagnosis and years since diagnosis. Results SIRs for second primary ovarian cancer were elevated over the entire study period (SIR, 1.24; 95% CI, 1.2 to 1.3), whereas the absolute rates declined with an estimated annual percentage change near 1% (−1.34% to −0.09% per year). Secular trends for second ovarian cancers were similar after estrogen receptor (ER) –positive and ER-negative breast cancers, whereas the age-specific patterns varied significantly by ER expression (P for interaction < .001). The largest SIR was among women age less than 50 years with ER-negative breast cancer (SIR, 4.35; 95% CI, 3.5 to 5.4). Conclusion Persistently elevated SIRs along with decreasing absolute rates over the entire study period suggest that ovarian cancers in both the general population and survivors of breast cancer are declining in parallel, possibly because of common risk factor exposures. Analytic studies are needed to further assess the parallel overall trends and the age-specific interaction by ER expression.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 4259-4259
Author(s):  
Aaron S. Mansfield ◽  
Mark A Lewis ◽  
Mrinal M. Patnaik ◽  
Noralane M Lindor ◽  
Matthew P Goetz ◽  
...  

Abstract Abstract 4259 Background: Patients with defective DNA repair mechanisms are at higher risk for developing cancer. BRCA1 and BRCA2 are proteins that coordinate DNA repair by homologous-recombination. Mutations in BRCA1 and BRCA2 are associated with an increased risk of cancers, namely breast, ovarian, and pancreatic, thus making these patients more likely to receive chemo- or radiation therapy. Additionally, secondary malignancies can be an unfortunate consequence of treatment with chemo- or radiation therapy. Although tumors with defective DNA repair mechanisms may be more susceptible to therapy, we hypothesized that patients with BRCA mutations that underwent chemotherapy or radiotherapy for treatment of breast or ovarian cancer would be at a higher risk of developing therapy- related myelodysplastic syndrome (t-MDS) or acute myeloid leukemia (t-AML). Methods: We accessed patient data from our institution maintained by the Mayo Clinic Life Sciences System using the Data Discovery and Query Builder. We searched for patients whose notes and diagnoses included the terms BRCA, and breast or ovarian cancer, and myelodysplastic syndrome or acute myeloid leukemia. We searched our records from 1/1/1995–7/15/2011. We cross-referenced our findings to a database of patients who were diagnosed with a BRCA mutation through our department of medical genetics. Secondly, we searched the National Cancer Institute's Surveillance Epidemiology and End Results (SEER) database for female patients who developed AML after the diagnosis or breast or ovarian cancer from the years 1973–2008 using ratio and multiple primaries standardized incidence ratios sessions. Results: We identified 220 patients with a BRCA mutation, of which 73 received chemotherapy. There were two patients with BRCA mutations that developed t-AML following treatment for breast cancer, and one patient with a BRCA mutation who developed t-AML following treatment for ovarian cancer (Table 1). Manual data extraction from the list of patients with BRCA mutations diagnosed at our institution only identified one of these patients, as two obtained their testing through another institution. We did not identify any patients with BRCA mutations who developed t-MDS following treatment for breast or ovarian cancer. The latency between diagnosis of the primary cancer and the diagnosis or t-AML was 24 months for two patients, and 22 years for the other. From our search of the SEER database we found 649 patients who developed AML after a diagnosis of breast cancer, and 98 patients who developed AML after a diagnosis of ovarian cancer. These patients represented 0.1% and 0.2% of evaluable breast and ovarian cases respectively. The latency from time of diagnosis of the primary cancer to that of AML was 58 months (29–113 interquartile range) for breast cancer and 47 months (29–91) for ovarian cancer. The observed number of patients with AML following the diagnosis of breast or ovarian cancer was 1.68 and 4.74 times higher than that expected of the general population, respectively (both p<0.05). We were not able to stratify patients based on the presence of a BRCA mutation due to the limitations of the database. Conclusions: We identified three patients with confirmed BRCA mutations and t-AML at our institution. Although this does not represent a strong association, patients at risk for BRCA mutations do not always undergo testing. Thus, our results may not fully represent whether there is an association with BRCA mutations and t-MDS or t-AML. Using the SEER database, we confirmed that patients who were diagnosed with breast or ovarian cancer subsequently had a higher incidence of AML than the general population, although we were not able to test if patients with BRCA mutations are at higher risk of t-MDS or t-AML. Disclosures: No relevant conflicts of interest to declare.


2016 ◽  
Vol 73 (14) ◽  
pp. 1037-1041 ◽  
Author(s):  
Marklie Munroe ◽  
Jill Kolesar

Abstract Purpose The pharmacology, clinical efficacy, safety, dosage and administration, and role in therapy of olaparib, a first-in-class treatment for advanced treatment-refractory ovarian cancer, are reviewed. Summary Olaparib (Lynparza, AstraZeneca) is an oral inhibitor of poly(ADP-ribose) polymerase (PARP) proteins that play a key role in DNA repair and genomic stability. Olaparib is indicated for use in treating certain patients with advanced, recurrent ovarian cancer who have mutations of the breast cancer 1 gene (BRCA1) or breast cancer 2 gene (BRCA2). In patients with BRCA-mutated cancers, olaparib blocks vital PARP-mediated tumor cell DNA repair mechanisms, leading to “synthetic lethality” and selective tumor cell death. In Phase II clinical trials including patients with platinum-sensitive, platinum-resistant, and platinum-refractory ovarian cancers, olaparib significantly improved progression-free survival, with similar rates of response reported in patients with BRCA1- and BRCA2-mutated disease. Olaparib is generally well tolerated; the most commonly reported adverse events in clinical trials were mild nausea, fatigue, vomiting, and diarrhea. Severe anemia and severe fatigue can occur in association with olaparib treatment. Concurrent administration of olaparib and strong or moderate inducers or inhibitors of cytochrome P-450 isozyme 3A should be avoided, as use of those agents may alter plasma concentrations of olaparib. Conclusion Olaparib is a novel PARP inhibitor that is efficacious and well tolerated in patients with BRCA-mutated advanced ovarian cancers who have received three or more lines of prior treatment.


2010 ◽  
Vol 28 (22) ◽  
pp. 3570-3576 ◽  
Author(s):  
Bryan T.J. Hennessy ◽  
Kirsten M. Timms ◽  
Mark S. Carey ◽  
Alexander Gutin ◽  
Larissa A. Meyer ◽  
...  

Purpose The prevalence of BRCA½ mutations in germline DNA from unselected ovarian cancer patients is 11% to 15.3%. It is important to determine the frequency of somatic BRCA½ changes, given the sensitivity of BRCA-mutated cancers to poly (ADP ribose) polymerase-1 (PARP1) inhibitors and platinum analogs. Patients and Methods In 235 unselected ovarian cancers, BRCA½ was sequenced in 235, assessed by copy number analysis in 95, and tiling arrays in 65. 113 tumors were sequenced for TP53. BRCA½ transcript levels were assessed by quantitative polymerase chain reaction in 220. When available for tumors with BRCA½ mutations, germline DNA was sequenced. Results Forty-four mutations (19%) in BRCA1 (n = 31)/BRCA2 (n = 13) were detected, including one homozygous BRCA1 intragenic deletion. BRCA½ mutations were particularly common (23%) in high-grade serous cancers. In 28 patients with available germline DNA, nine (42.9%) of 21 and two (28.6%) of seven BRCA1 and BRCA2 mutations were demonstrated to be somatic, respectively. Five mutations not previously identified in germline DNA were more commonly somatic than germline (four of 11 v one of 17; P = .062). There was a positive association between BRCA1 and TP53 mutations (P = .012). BRCA½ mutations were associated with improved progression-free survival (PFS) after platinum-based chemotherapy in univariate (P = .032; hazard ratio [HR] = 0.65; 95% CI, 0.43 to 0.98) and multivariate (P = .019) analyses. BRCA½ deficiency, defined as BRCA½ mutations or expression loss (in 24 [13.3%] BRCA½–wild-type cancers), was present in 67 ovarian cancers (30%) and was also significantly associated with PFS in univariate (P = .026; HR = 0.67; 95% CI, 0.47 to 0.96) and multivariate (P = .008) analyses. Conclusion BRCA½ somatic and germline mutations and expression loss are sufficiently common in ovarian cancer to warrant assessment for prediction of benefit in clinical trials of PARP1 inhibitors.


Sign in / Sign up

Export Citation Format

Share Document