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Hereditary breast and ovarian cancer (HBOC) syndrome is a genetic condition that increases the risk of breast cancer by 80% and that of ovarian cancer by 40%. The most common pathogenic variants (PVs) causing HBOC occur in the BRCA1 gene, with more than 3850 reported mutations in the gene sequence. The prevalence of specific PVs in BRCA1 has increased across populations due to the effect of founder mutations. Therefore, when a founder mutation is identified, it becomes key to improving cancer risk characterization and effective screening protocols. The only founder mutation described in the Mexican population is the deletion of exons 9 to 12 of BRCA1 (BRCA1Δ9-12), and its description focuses on the gene sequence, but no transcription profiles have been generated for individuals who carry this gene. In this study, we describe the transcription profiles of cancer patients and healthy individuals who were heterozygous for PV BRCA1Δ9-12 by analyzing the differential expression of both alleles compared with the homozygous BRCA1 control group using RT-qPCR, and we describe the isoforms produced by the BRCA1 wild-type and BRCA1Δ9-12 alleles using nanopore long-sequencing. Using the Kruskal-Wallis test, our results showed a similar transcript expression of the wild-type allele between the healthy heterozygous group and the homozygous BRCA1 control group. An association between the recurrence and increased expression of both alleles in HBOC patients was also observed. An analysis of the sequences indicated four wild-type isoforms with diagnostic potential for discerning individuals who carry the PV BRCA1Δ9-12 and identifying which of them has developed cancer.

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This study aimed to investigate prognosis and survival differences in 82 breast cancer patients with germline pathogenic/likely pathogenic variants (PVs) treated and followed at the Breast Unit of the Instituto Nacional de Cancerología, Colombia (INC-C) between 2018 and 2021. Median age at diagnosis was 46 years, with 62.2% presenting locally advanced tumors, 47.6% histological grade 3, and 35.4% with triple-negative breast cancer (TNBC) subtype. Most carriers, 74.4% (61/82), had PVs in known breast cancer susceptibility genes (i.e., "associated gene carriers" group, considered inherited breast cancer cases): BRCA2 (30), BRCA1 (14), BARD1 (4), RAD51D (3), TP53 (2), PALB2 (2), ATM (2), CHEK2 (1), RAD51C (1), NF1 (1), and PTEN (1). BRCA1-2 represented 53.7%, and homologous recombination DNA damage repair (HR-DDR) genes associated with breast cancer risk accounted for 15.9%. Patients with PVs in non-breast-cancer risk genes were combined in a different category (21/82; 25.6%) (i.e., "non-associated gene carriers" group, considered other breast cancer cases). Median follow-up was 38.1 months, and 24% experienced recurrence, with 90% being distant. The 5-year Disease-Free Survival (DFS) for inherited breast cancer cases was 66.5%, and for other breast cancer cases it was 88.2%. In particular, for carriers of PVs in the BRCA2 gene, it was 37.6%. The 5-year Overall Survival (OS) rates ranged from 68.8% for those with PVs in BRCA2 to 100% for those with PVs in other HR-DDR genes. Further studies are crucial for understanding tumor behavior and therapy response differences among Colombian breast cancer patients with germline PVs.

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BACKGROUND: A detailed understanding of the genetic basis of cancer is of great interest to public health monitoring programs. Although many studies have been conducted in Brazil, a global view on the molecular profile related to hereditary breast and ovarian cancer (HBOC) in this large and heterogeneous population is lacking. METHODS: A systematic review following the PRISMA guidelines was conducted in three electronic databases (PubMed, BIREME and SciELO). Brazilian studies covering molecular analysis of genes related to HBOC, published until December 2023, were considered. RESULTS: We identified 35 original studies that met all the inclusion criteria. A total of 137 distinct mutations were found in the BRCA1 gene, but four of them corresponded to 44.5% of all mutations found in this gene. The c.5266dupC BRCA1 mutation was responsible for 26.8% of all pathogenic mutations found in the BRCA1 gene in patients with clinical criteria for HBOC from the Brazilian population. Considering all studies that track this mutation in the BRCA1 gene, we found a frequency of 2% (120/6008) for this mutation in Brazilian patients. In the BRCA2 gene, the four most frequent mutations corresponded to 29.2% of pathogenic mutations. Even though it was tracked by few studies, the c.156_157insAlu mutation was responsible for 9.6% of all pathogenic mutations reported in the BRCA2 gene. Seventeen studies found pathogenic mutations in other non-BRCA genes, the c.1010G > A mutation in the TP53 gene being the most frequent one. Considering all studies that screened for this specific mutation in patients with the clinical criteria for HBOC, the frequency of c.1010G > A was estimated at 1.83% (61/3336). CONCLUSIONS: Despite significant molecular heterogeneity among mutations in HBOC patients from Brazil, three mutations deserve to be highlighted, c.5266dupC, c.156_157insAlu and c.1010G > A in the BRCA1, BRCA2 and TP53 genes, respectively. With more than 200 records, these three mutations play a vital role in the pathology of breast and ovarian cancer in Brazil. The data collected shed light on the subject, but there is still not enough data from certain subpopulations.

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We determined the frequency and mutational spectrum of BRCA1 and BRCA2 in a series of patients at high risk for developing breast cancer from Brazil. A total of 1267 patients were referred for BRCA genetic testing, and no obligation of fulfilling criteria of mutation probability methods for molecular screening was applied. Germline deleterious mutations in BRCA1/2 (i.e., pathogenic/likely pathogenic variants) were identified in 156 out of 1267 patients (12%). We confirm recurrent mutations in BRCA1/2, but we also report three novel mutations in BRCA2, not previously reported in any public databases or other studies. Variants of unknown significance (VUS) represent only 2% in this dataset and most of them were detected in BRCA2. The overall mutation prevalence in BRCA1/2 was higher in patients diagnosed with cancer at age > 35 years old, and with family history of cancer. The present data expand our knowledge of BRCA1/2 germline mutational spectrum, and it is a valuable clinical resource for genetic counseling and cancer management programs in the country.

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Abstract Objective The study aimed to characterize the clinical, histological, and immunohistochemical profile of women with invasive breast cancer, according to the risk for Hereditary Predisposition Breast and Ovarian Cancer Syndrome in a Brazilian population. Methods This is a retrospective study performed from a hospital-based cohort of 522 women, diagnosed with breast cancer treated at an oncology referral center in the Southeast region of Brazil, between 2014 and 2016. Results Among the 430 women diagnosed with invasive breast cancer who composed the study population, 127 (29.5%) were classified as at increased risk for hereditary predisposition to breast and ovarian cancer syndrome. There was a lower level of education in patients at increased risk (34.6%) when compared with those at usual risk (46.0%). Regarding tumor characteristics, women at increased risk had higher percentages of the disease diagnosed at an advanced stage (32.3%), and with tumors > 2cm (63.0%), with increased prevalence for both characteristics, when compared with those at usual risk. Furthermore, we found higher percentages of HG3 (43.3%) and Ki-67 ≥ 25% (64.6%) in women at increased risk, with prevalence being about twice as high in this group. The presence of triple-negative tumors was observed as 25.2% in women at increased risk and 6.0% in women at usual risk, with the prevalence of absence of biomarkers being 2.5 times higher among women in the increased risk group. Conclusion From the clinical criteria routinely used in the diagnosis of breast cancer, the care practice of genetic counseling for patients at increased risk of hereditary breast cancer in contexts such as Brazil is still scarce.

Resumo Objetivo O presente estudo buscou caracterizar o perfil clínico, histológico e imunohistoquímico de mulheres com câncer de mama invasivo segundo o risco para a Síndrome de Predisposição Hereditária ao Câncer de Mama e Ovário em uma população brasileira. Métodos Trata-se de um estudo retrospectivo realizado a partir de uma coorte hospitalar composta por 522 mulheres diagnosticadas com câncer de mama entre 2014 e 2016 assistidas em um centro de referência oncológica localizado na região sudeste brasileira. Resultados Entre as 430 mulheres diagnosticadas com câncer de mama invasivo que compuseram a população de estudo, 127 (29,5%) foram classificadas como de risco aumentado para a síndrome de predisposição hereditária ao câncer de mama e ovário. Verificou-se menor nível de escolaridade nas pacientes com risco aumentado (34,6%) quando comparadas àquelas consideradas como de risco habitual (46,0%). Quanto às características do tumor, as mulheres de risco aumentado apresentaram maiores percentuais de doença diagnosticada em estádio avançado (32,3%) e com tumores > 2cm (63,0%), com prevalência aumentada para ambas as características, quando comparadas àquelas de risco habitual. Ainda nas mulheres de risco aumentado, foram encontrados maiores percentuais de GH3 (43,3%) e Ki-67 ≥ 25% (64,6%), com prevalência cerca de duas vezes maior neste grupo. A presença de tumores triplo-negativos foi observada em 25,2% nas mulheres de risco aumentado e 6,0% nas mulheres de risco habitual, com prevalência de ausência de biomarcadores 2,5 vezes maior entre as mulheres do grupo de risco aumentado. Conclusão A partir dos critérios clínicos rotineiramente utilizados no diagnóstico do câncer de mama, a prática assistencial do aconselhamento genético para as pacientes com risco aumentado de câncer de mama hereditário em contextos como o do Brasil ainda é escarça.

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OBJECTIVE: To evaluate the risks, benefits, and utility of testing for adult-onset hereditary breast and ovarian cancer (HBOC) in adolescents and young adults. STUDY DESIGN: We evaluated interest in genetic testing of adolescents for adult-onset HBOC genes through semistructured interviews with mothers and adolescents who had previously participated in breast cancer research or had pursued (mothers) clinical testing for HBOC. RESULTS: The majority of mothers (73%) and daughters (75%) were interested in the daughter having genetic testing and were motivated by the future medical utility and current social utility of relieving anxiety and allowing them to prepare. Mothers and daughters both reported that approximately 3 years in the future was the best time to test the daughter regardless of the current age of the daughter. Overall, both mothers and daughters expressed the importance of the involvement of the mother to provide educational and emotional support but ultimately it was the daughter's decision to test. Balancing the independence and maturity of the daughter while reinforcing communication and support within the dyad was a prominent theme throughout the interviews. CONCLUSIONS: There is interest among some high-risk adolescents and young adults to engage in genetic counseling and undergo testing. Providing pretest and posttest genetic counseling, assessing preferences for parent involvement, and offering psychosocial support may be important if genetic testing for HBOC is offered to adolescents and young adults before age 25 years.

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The aim of this study was to assess the prevalence of germline variants in cancer-predisposing genes by either targeted (BRCA1/2) or multigene NGS panel in a high-risk Hereditary Breast and Ovarian Cancer (HBOC) cohort. Samples from 824 Caucasian probands were retrospectively collected and the impact of genetic diagnosis and genetic variants epidemiology in this cohort was evaluated. Performance of risk-reducing prophylactic measures, such as prophylactic mastectomy and/or prophylactic oophorectomy, was assessed through clinical follow-up of patients with a positive genetic result. Pathogenic variants predisposing to HBOC were identified in 11.9% (98/824) individuals at BRCA2 (47/98), BRCA1 (24/98), PALB2 (8/51), ATM (7/51), CHEK2 (6/51) MSH6, (2/51), RAD51C (2/51) and TP53 (2/386). Of them, 11 novel pathogenic variants and 12 VUS were identified, characterized, and submitted to ClinVar. Regarding clinical impact, the risk of developing basal or Her2 breast cancer was increased 15.7 times or 37.5 times for BRCA1 and MSH6 pathogenic variants respectively. On the contrary, the risk of developing basal or luminal A breast cancer was reduced to 81% or 77% for BRCA2 and BRCA1 pathogenic variants, respectively. Finally, 53.2% of individuals testing positive for class IV/V variants underwent prophylactic surgery (mastectomy, oophorectomy or both) being significantly younger at the cancer diagnosis than those undertaking prophylactic measures (p = 0.008). Of them, 8 carried a pathogenic/likely pathogenic variant in other genes different from BRCA1 and BRCA2, and the remaining (46.7%) decided to continue with clinical follow-up. No differences in pathogenicity or risk of developing cancer were found for BRCA1/2 between targeted and multigene sequencing strategies; however, NGS was able to resolve a greater proportion of high-risk patients.

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To analyze the occurrence of genetic mutations in a sample of patients with high risk of breast cancer in Florianopolis/ SC from December 1st, 2021, to January 31, 2022. Methods: An observational, descriptive and retrospective study carried out through data collection of a preexisting database. A total of 194 tests were analyzed. Of these, 192 met the inclusion criteria and composed the final sample of 205 genes. Data were classified and reported the frequency and percentage of the variables: gene and presence or absence of mutation. Results: Mean age of the analyzed patients was 52.3 years, and most underwent the test due to personal history of breast cancer (80%). Clinical significance classification showed that, of the 192 gene panels, 62% were variants of uncertain significance; 14% were pathogenic; and 24%, negative. Of the 205 mutations, the most prevalent genes were: ATM 8.7%, MUTYH 5.8%, POLE 5.8%, BRCA2 4.8%, MSH6 4.8% and RECQL4 4.8%. Of the pathogenic tests regarding genetic predisposition to cancer (n=38/14.1%), the most common mutations were MUTYH (23%) and BRCA1 (15%), with mean age of 52 years (±14.3). In variants of uncertain significance panels (n=168/62%) the frequency rates were ATM (7.7%), POLE (7.1%) and MSH6 (5.9%) genes. The high penetrance genes were present in 18% of the genetic predisposition to cancer panels. Of those with positive family history (n=40), 19% of the genes were pathogenic, 53% were variants of uncertain significance; and 26% were negative. Furthermore, in patients with pathogenic mutations and positive family history (n=11), the most common mutations were in BRCA1 (27%) and BRCA2 (27%). Of the patients who tested due to personal history (n=152), 64% of the genes presented variants of uncertain significance, 13% were pathogenic and 22% were negative.

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BACKGROUND: It is estimated that 5-10% of breast cancer cases are hereditary. The identification of pathogenic germline variants allows individualized preventive health care, improvement of clinical management and genetic counseling. Studies in ethnically admixed Latin American populations have identified regions with increased frequency of deleterious variants in breast cancer predisposing genes. In this context, the Brazilian population exhibits great genetic heterogeneity, and is not well represented in international databases, which makes it difficult to interpret the clinical relevance of germline variants. METHODS: We evaluated the frequency of pathogenic/likely pathogenic (P/LP) germline variants in up to 37 breast cancer predisposing genes, in a cohort of 105 breast and/or ovarian cancer Brazilian women referred to two research centers between 2014 and 2019. RESULTS: A total of 22 patients (21%) were found to carry P/LP variants, and 16 VUS were detected in 15 patients (14.3%). Additionally, a novel pathogenic ATM intragenic deletion was identified in an early-onset breast cancer. We also detected a BRCA1 pathogenic variant (c.5074+2T>C) in higher frequency (10×) than in other studies with similar cohorts. CONCLUSIONS: Our findings contribute to the characterization of the genetic background of breast cancer predisposition in the Brazilian population as a useful resource to discriminate between deleterious variants and VUS, thus enabling improvement in the preventive health care and clinical management of carriers.

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The current study aimed to identify new breast and/or ovarian cancer predisposition genes. For that, whole-exome sequencing (WES) was performed in the germline DNA of 52 non-BRCA1/BRCA2/TP53 mutation carrier women at high-risk for hereditary breast and ovarian cancer (HBOC). All variants were classified using information from population and disease specific databases, in silico prediction tools and the American College of Medical Genetics and Genomics (ACMG) criteria. Loss of heterozygosity (LOH) of tumor samples and segregation analyses were performed whenever possible. The variants identified were investigated in a second, independent cohort of 17 BC cases. Pathogenic/Likely Pathogenic variants were identified in known cancer genes such as CHEK2, MUTYH, PMS2, and RAD51C. Rare and potentially pathogenic variants were identified in DNA repair genes (FAN1, POLQ, and RAD54L) and other cancer-related genes such as DROSHA and SLC34A2. Interestingly, the variant c.149T>G in the FAN1 gene was identified in two unrelated families, and exhibited LOH in the tumor tissue of one of them. In conclusion, this is the largest Brazilian WES study involving families at high-risk for HBOC which has brought novel insights into the role of potentially new genetic risk factors for hereditary breast and ovarian cancer.

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This literature review aims to inform and assist physicians and other health professionals in managing all information related to hereditary breast cancer, which is in constant and rapid growth, allowing for improvement in patient care and assistance. In addition, we seek to better identify which patients are eligible for the clinical criteria of association with risk of hereditary breast cancer, based on international recommendations and highlighting the main high and moderate penetrance genes that make up the multigenic panels for germline investigation in breast cancer, as well as the possibilities of clinical management that must be considered when complex decisions are required in clinical practice. Nowadays, there is more interest in population screening, in a greater supply of genetic tests, more genes included in multigene panels ­ allowing the search for genetic counseling ­, apart from the need for clinical-decision support.

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The use of gene panels introduces a new dilemma in the genetics field due to the high frequency of variants of uncertain significance (VUS). The objective of this study was to provide evidence that may help in the classification of these germline variants in terms of their clinical impact and association with the disease in question. A total of 52 unrelated women at-risk for HBOC and negative for BRCA1/BRCA2 pathogenic variants were evaluated through a gene panel comprising 14 breast and/or ovarian cancer susceptibility genes. Of the 453 germline variants identified, 15 variants (classes 3, 4, and 5) in the ATM, BRIP1, CHEK2, MRE11A, MUTHY, PALB2, RAD50, and RAD51C genes were evaluated via databases, co-segregation studies and loss of heterozygosity in the tumor. The co-segregation analysis allowed the establishment of an association with the presence of variants and the risk of cancer for variant c.316C>T in the BRIP1 gene. Four variants of uncertain significance showed loss of heterozygosity in the tumor (ATM c.4709T>C; CHEK2 c.1036C>T; PALB2 c.1001A>G, and RAD50 c.281T>C), which is an indication of pathogenicity. Thus, the present study provides novel evidence that favors the association of variants in moderate-risk genes with the development of hereditary breast cancer.

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Hereditary breast and ovarian cancer (HBOC) syndrome is mainly caused by mutations in the BRCA1 and BRCA2 genes. The 3'UTR region allows for the binding of microRNAs, which are involved in genetic tune regulation. We aimed to identify allelic variants on 3'UTR miRNA-binding sites in the BRCA1 and BRCA2 genes in HBOC patients. Blood samples were obtained from 50 patients with HBOC and from 50 controls. The 3'UTR regions of BRCA1 and BRCA2 were amplified by PCR and sequenced to identify genetic variants using bioinformatics tools. We detected nine polymorphisms in 3'UTR, namely: four in BRCA1 (rs3092995 (C/G), rs8176318 (C/T), rs111791349 (G/A), and rs12516 (C/T)) and five in BRCA2 (rs15869 (A/C), rs7334543 (A/G), rs1157836 (A/G), and rs75353978 (TT/del TT)). A new variant in position c.*457 (A/C) on 3'UTR of BRCA2 was also identified. The following three variants increased the risk of HBOC in the study population: rs111791349-A, rs15869-C, and c.*457-C (odds ratio (OR) range 3.7-15.4; p < 0.05). Genetic variants into the 3'UTR of BRCA1 and BRCA2 increased the risk of HBOC between 3.7-15.4 times in the study population. The presence/absence of these polymorphisms may influence the loss/creation of miRNA binding sites, such as hsa-miR-1248 in BRCA1 3'UTR or the hsa-miR-548 family binding site in BRCA2. Our results add new evidence of miRNA participation in the pathogenesis of HBOC.

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OBJECTIVE: There is a lack of information describing Brazilian women at risk of hereditary breast and ovarian cancer syndrome (HBOC) who undergo genetic cancer risk assessment (GCRA). This study aims to characterize the psychosocial profile of women at risk for HBOC at their first GCRA to obtain an overview of their families' profiles and the challenges of the oncogenetics setting. METHODS: This was a cross-sectional study in which interviews were conducted with 83 cancer-affected women at their first GRCA appointment after the pedigree draw. Tools to evaluate psychological outcomes were applied. The pedigree genogram and ecomap were constructed and analyzed with content analysis using the "life course perspective" theory. RESULTS: Individuals perceived their breast/ovarian cancer risk to be equal to that of the general population, although they were highly concerned about developing cancer. No evidence of anxiety or depressive symptoms was identified. Participants used the coping strategy of searching for religiosity. The genograms and ecomaps resulted in five major themes: support and social support; attitudes, feelings and emotions; cancer causes; communication; and relationships with relatives. Individuals between 20-29 years of age and those with no family history of cancer tended not to communicate with relatives, which may indicate future problems in the GCRA process regarding genetic testing. CONCLUSIONS: This study demonstrated that knowing the families who undergo the GCRA process can help professionals provide more individualized and thorough attention during GCRA and genetic testing, which results in better follow-up and prevention strategies.

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Abstract Introduction: Breast cancer is the most common neoplasia of women from all over the world especially women from Colombia. 5%­10% of all cases are caused by hereditary factors, 25% of those cases have mutations in the BRCA1/BRCA2 genes. Objective: The purpose of this study was to identify the mutations associated with the risk of familial breast and/or ovarian cancer in a population of Colombian pacific. Methods: 58 high-risk breast and/or ovarian cancer families and 20 controls were screened for germline mutations in BRCA1 and BRCA2, by Single Strand Conformation Polymorphism (SSCP) and sequencing. Results: Four families (6.9%) were found to carry BRCA1 mutations and eight families (13.8%) had mutations in BRCA2. In BRCA1, we found three Variants of Uncertain Significance (VUS), of which we concluded, using in silico tools, that c.81­12C>G and c.3119G>A (p.Ser1040Asn) are probably deleterious, and c.3083G>A (p.Arg1028His) is probably neutral. In BRCA2, we found three variants of uncertain significance: two were previously described and one novel mutation. Using in silico analysis, we concluded that c.865A>G (p.Asn289Asp) and c.6427T>C (p.Ser2143Pro) are probably deleterious and c.125A>G (p.Tyr42Cys) is probably neutral. Only one of them has previously been reported in Colombia. We also identified 13 polymorphisms (4 in BRCA1 and 9 in BRCA2), two of them are associated with a moderate increase in breast cancer risk (BRCA2 c.1114A>C and c.8755­66T>C). Conclusion: According to our results, the Colombian pacific population presents diverse mutational spectrum for BRCA genes that differs from the findings in other regions in the country.

Resumen Introducción: El cáncer de mama es la neoplasia más común en mujeres de todo el mundo, y, también de Colombia. 5% a 10% de todos los casos son causados por factores hereditarios; 25% de estos casos tienen mutaciones en los genes BRCA1/BRCA2. Objetivo: El propósito de este estudio fue el de identificar mutaciones asociadas con riesgo de cáncer de mama y/u ovario familiar en pacientes del pacífico colombiano. Métodos: Fueron revisados para mutaciones en BRCA1 y BRCA2 de línea germinal mediante SSCP y secuenciación 58 familias de alto riesgo para cáncer de mama y/u ovario y 20 controles Resultados: cuatro familias (6.9%) presentaron mutaciones en BRCA1 y ocho familias (13.8%) en BRCA2. En BRCA1, encontramos tres variantes de significado clínico desconocido (VUS), de las cuales concluimos, usando herramientas bioinformáticas, que c.81­12C>G y c.3119G>A (p.Ser1040Asn) son probablemente deletéreas, y c.3083G>A (p.Arg1028His) es probablemente neutral. En BRCA2, encontramos tres VUS: una mutación nueva y dos previamente descritas, usando análisis bioinformáticos, concluimos que c.865A>G (p.Asn289Asp) y c.6427T>C (p.Ser2143Pro) son probablemente deletéreas y c.125A>G (p.Tyr42Cys) es probablemente neutral. Solo una de ellas ha sido reportada previamente en Colombia. También identificamos 13 polimorfismos (4 en BRCA1 y 9 en BRCA2), dos de ellos asociados con un moderado incremento del riesgo para cáncer de mama (BRCA2 c.1114A>C and c.8755­66T>C). Conclusión: de acuerdo con nuestros resultados, la población del suroccidente colombiano presenta un espectro mutacional diverso para los genes BRCA que difiere de lo encontrado en otras regiones del país.

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INTRODUCTION: Breast cancer is the most common neoplasia of women from all over the world especially women from Colombia. 5%-10% of all cases are caused by hereditary factors, 25% of those cases have mutations in the BRCA1/BRCA2 genes. OBJECTIVE: The purpose of this study was to identify the mutations associated with the risk of familial breast and/or ovarian cancer in a population of Colombian pacific. METHODS: 58 high-risk breast and/or ovarian cancer families and 20 controls were screened for germline mutations in BRCA1 and BRCA2, by Single Strand Conformation Polymorphism (SSCP) and sequencing. RESULTS: Four families (6.9%) were found to carry BRCA1 mutations and eight families (13.8%) had mutations in BRCA2. In BRCA1, we found three Variants of Uncertain Significance (VUS), of which we concluded, using in silico tools, that c.81-12C>G and c.3119G>A (p.Ser1040Asn) are probably deleterious, and c.3083G>A (p.Arg1028His) is probably neutral. In BRCA2, we found three variants of uncertain significance: two were previously described and one novel mutation. Using in silico analysis, we concluded that c.865A>G (p.Asn289Asp) and c.6427T>C (p.Ser2143Pro) are probably deleterious and c.125A>G (p.Tyr42Cys) is probably neutral. Only one of them has previously been reported in Colombia. We also identified 13 polymorphisms (4 in BRCA1 and 9 in BRCA2), two of them are associated with a moderate increase in breast cancer risk (BRCA2 c.1114A>C and c.8755-66T>C). CONCLUSION: According to our results, the Colombian pacific population presents diverse mutational spectrum for BRCA genes that differs from the findings in other regions in the country.

INTRODUCCIÓN: El cáncer de mama es la neoplasia más común en mujeres de todo el mundo, y, también de Colombia. 5% a 10% de todos los casos son causados por factores hereditarios; 25% de estos casos tienen mutaciones en los genes BRCA1/BRCA2. OBJETIVO: El propósito de este estudio fue el de identificar mutaciones asociadas con riesgo de cáncer de mama y/u ovario familiar en pacientes del pacífico colombiano. MÉTODOS: Fueron revisados para mutaciones en BRCA1 y BRCA2 de línea germinal mediante SSCP y secuenciación 58 familias de alto riesgo para cáncer de mama y/u ovario y 20 controles. RESULTADOS: cuatro familias (6.9%) presentaron mutaciones en BRCA1 y ocho familias (13.8%) en BRCA2. En BRCA1, encontramos tres variantes de significado clínico desconocido (VUS), de las cuales concluimos, usando herramientas bioinformáticas, que c.81­12C>G y c.3119G>A (p.Ser1040Asn) son probablemente deletéreas, y c.3083G>A (p.Arg1028His) es probablemente neutral. En BRCA2, encontramos tres VUS: una mutación nueva y dos previamente descritas, usando análisis bioinformáticos, concluimos que c.865A>G (p.Asn289Asp) y c.6427T>C (p.Ser2143Pro) son probablemente deletéreas y c.125A>G (p.Tyr42Cys) es probablemente neutral. Solo una de ellas ha sido reportada previamente en Colombia. También identificamos 13 polimorfismos (4 en BRCA1 y 9 en BRCA2), dos de ellos asociados con un moderado incremento del riesgo para cáncer de mama (BRCA2 c.1114A>C and c.8755­66T>C). CONCLUSIÓN: de acuerdo con nuestros resultados, la población del suroccidente colombiano presenta un espectro mutacional diverso para los genes BRCA que difiere de lo encontrado en otras regiones del país.

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BACKGROUND: About 5-10% of breast/ovarian cancers are hereditary. However, for a large proportion of cases (around 50%), the genetic cause remains unknown. These cases are grouped in a separated BRCAX category. The aim of this study was to identify genomic alterations in BRCA1/BRCA2 wild-type tumor samples from women with family history strongly suggestive of hereditary breast/ovarian cancer. RESULTS: A cohort of 31 Brazilian women was included in the study. Using the GISTIC algorithm, we identified 20 regions with genomic gains and 31 with losses. The most frequent altered regions were 1q21.2, 6p22.1 and 8p23.3 in breast tumors and Xq26 and Xp22.32-22.31 among the ovarian cancer cases. An interesting association identified was the loss of 22q13.31-13.32 and the presence of ovarian cancer cases. Among the genes present in the frequently altered regions, we found FGFR1, NSMCE2, CTTN, CRLF2, ERBB2, STARD3, MIR3201 and several genes of RAET and ULBP family. CONCLUSIONS: In conclusion, our results suggest that alterations on chromosomes 1, 6, 8 and X are common on BRCAX tumors and that the loss on 22q can be associated with the presence of ovarian cancer. METHODS: DNA copy number alterations were analyzed by 60K array comparative genomic hybridization in breast and ovarian FFPE tumors.

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BACKGROUND: The role of deep intronic variants in hereditary cancer susceptibility has been largely understudied. Previously, the BRCA2 c.6937 + 594T>G variant has been shown to preferentially promote the inclusion of a 95 nucleotide cryptic exon and to introduce a premature termination codon. Our objective was to further assess the pathogenicity of the BRCA2 c.6937 + 594T>G deep intronic variant. PATIENTS AND METHODS: We examined the association between BRCA2 c.6937 + 594T>G and breast cancer (BC) risk in 464 BC cases and 497 noncancer controls from Puerto Rico. RESULTS: The overall frequency of the G allele was 2.1% in this population. There was no association between the TG/GG genotypes and BC risk in the uncorrected model and after correcting for confounders. There was only one carrier of the GG genotype. This individual did not have personal or family history of cancer and did not meet the National Comprehensive Cancer Network criteria for hereditary cancer genetic testing. CONCLUSIONS: Although previous work has demonstrated that the BRCA2 c.6937 + 594T>G variant affects splicing, this association study does not support a pathogenic role for the BRCA2 c.6937 + 594T>G intronic variant in breast and ovarian cancer syndrome susceptibility. Furthermore, it emphasizes the need to take into account multiple diverse populations in association studies for the assessment of variant pathogenicity.

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OBJECTIVES: To evaluate the accuracy of algorithms for predicting BRCA1/2 germ-line mutation carrier probability, and to identify factors that could improve their performance among Brazilian women with ovarian cancer (OC). STUDY DESIGN: In this cross-sectional study, we enrolled patients (unselected for family history of cancer) undergoing treatment or follow-up for OC in a single centre in Brazil. Clinical and demographic data, including family history of cancer, were obtained. Blood samples were collected for genetic testing. MAIN OUTCOME MEASURES: The entire coding sequence of BRCA1 and BRCA2 was evaluated for mutations. Mutation carrier probability was calculated using BOADICEA, BRCAPRO, Myriad and the Manchester score. Sensitivity, specificity, positive and negative predictive values, and area under the receiver operating characteristic curves (AUC) were calculated for each algorithm. Logistic regression was used to detect additional factors associated with BRCA1/2 status, and these were added to the algorithms before recalculating the AUCs. RESULTS: BRCA1/2 mutations were identified in 19 of the 100 included patients. BOADICEA outperformed other algorithms (sensitivity, 73.7%; specificity, 87.7%; AUC, 0.87, with a threshold of a 10% risk of mutation). Later menarche was associated with the presence of a BRCA1/2 mutation. Although adding age at menarche resulted in a larger AUC for all models, this increase was significant only for the Myriad algorithm. CONCLUSION: A BOADICEA risk evaluation of 10% or more most accurately predicted BRCA1/2 status, and the inclusion of age at menarche tended to improve the performance of all algorithms. Using these tools could reduce the number of tests, but at the expense of missing a significant proportion of mutation carriers.

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Germline mutations in BRCA1 or BRCA2 (BRCA) are responsible for 5-15% of breast (BC) and ovarian cancers (OC), predisposing to the development of early onset and often multiple primary tumors. Since mutation carriers can benefit from risk-reducing interventions, the identification of individuals with hereditary breast and ovarian cancer (HBOC) syndrome has a significant clinical impact. We assessed whether a panel assay for recurrent Hispanic BRCA mutations (HISPANEL) has an adequate breadth of coverage to be suitable as a cost effective screening tool for HBOC in a cohort of patients from Southern Brazil. A multiplex, PCR-based panel was used to genotype 232 unrelated patients for 114 germline BRCA mutations, finding deleterious mutations in 3.5% of them. This mutation prevalence is within the range detected by the HISPANEL among BC patients unselected for family history in other Latin American settings. The HISPANEL would have accounted for 27% of the BRCA mutations detected by complete sequencing in a comparison cohort (n = 193). This prevalence may be region-specific since significant differences in population structure exist in Brazil. Comprehensive analysis of BRCA in a larger set of HBOC patients from different Brazilian regions is warranted, and the results could inform customization of the HISPANEL as an affordable mutation screening tool.

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