RESUMO
The aim of the study was to evaluate the impact of a regional population-based genetic testing program on the incidence of ovarian cancer in West Pomerania. Between 1999 and 2010, a total of 37,552 women ages 35 to 70 were tested for three BRCA1 founder mutations at the outpatient genetics clinic of the Pomeranian Medical University in Szczecin, Poland. A total of 641 women were found to carry a mutation (1.7%) and of these, 220 had a prophylactic oophorectomy (34.3%). A total of 12 women had an occult cancer diagnosed at the time of prophylactic oophorectomy (5.5%). We estimate that 26 more ovarian cancers would have been diagnosed by January 2015 in the absence of these oophorectomies and that an additional 25 cancers will be prevented in the future (total 51). During this period, 1611 ovarian cancers were diagnosed in the region; therefore we estimate that approximately 1.6% of ovarian cancers were prevented between 1999 and 2015 by our genetic testing program. We conclude that the prophylactic oophorectomies performed between 1999 and 2010 as a result of widespread BRCA1 mutation testing have reduced the incidence of ovarian cancer in Pomerania by a small amount (about 1.6%), and that the impact of genetic testing will increase in the coming years.
Assuntos
Proteína BRCA1/genética , Predisposição Genética para Doença , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/genética , Adulto , Idoso , Feminino , Efeito Fundador , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Ovariectomia , PolôniaRESUMO
BACKGROUND: Mutations in the BRCA1, BRCA2 and PALB2 genes are well-established risk factors for the development of breast and/or ovarian cancer. The frequency and spectrum of mutations in these genes has not yet been examined in the population of Southern Poland. METHODS: We examined the entire coding sequences of the BRCA1 and BRCA2 genes and genotyped a recurrent mutation of the PALB2 gene (c.509_510delGA) in 121 women with familial and/or early-onset breast or ovarian cancer from Southern Poland. RESULTS: A BRCA1 mutation was identified in 11 of 121 patients (9.1 %) and a BRCA2 mutation was identified in 10 of 121 patients (8.3 %). Two founder mutations of BRCA1 accounted for 91 % of all BRCA1 mutation carriers (c.5266dupC was identified in six patients and c.181 T > G was identified in four patients). Three of the seven different BRCA2 mutations were detected in two patients each (c.9371A > T, c.9403delC and c.1310_1313delAAGA). Three mutations have not been previously reported in the Polish population (BRCA1 c.3531delT, BRCA2 c.1310_1313delAAGA and BRCA2 c.9027delT). The recurrent PALB2 mutation c.509_510delGA was identified in two patients (1.7 %). CONCLUSIONS: The standard panel of BRCA1 founder mutations is sufficiently sensitive for the identification of BRCA1 mutation carriers in Southern Poland. The BRCA2 mutations c.9371A > T and c.9403delC as well as the PALB2 mutation c.509_510delGA should be included in the testing panel for this population.
RESUMO
The purpose of this study is to determine the prevalence of PALB2 mutations among breast cancer families from the United States. The PALB2 gene was screened for mutations in 90 familial breast cancer patients from the Creighton University Breast Cancer Family Registry. These patients had previously tested negative for mutations in BRCA1 and BRCA2. Two of 90 breast cancer patients (2.2 %) were found to carry a truncating mutation in PALB2 (c.2411_2412delCT and c.2053delC). Both probands were diagnosed with breast cancer before age 35 and each had three relatives with breast cancer. Mutations in PALB2 are less common than BRCA1 and BRCA2 in familial breast cancer patients. However, testing for PALB2 mutations is a useful adjunct for patients undergoing testing for BRCA1 and BRCA2.
Assuntos
Neoplasias da Mama/genética , Mutação , Proteínas Nucleares/genética , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína do Grupo de Complementação N da Anemia de Fanconi , Feminino , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Linhagem , Prevalência , Sistema de Registros , Estados Unidos , Adulto JovemRESUMO
Women who carry a BRCA1 or BRCA2 mutation are at high risk of breast and ovarian cancer, and may be at moderately increased risk of other cancer types. This review examines studies to date that have evaluated the risk of BRCA1 and BRCA2 mutations for colorectal cancer. Accurate knowledge of colorectal cancer risk in BRCA1/2 carriers is important, because colonoscopy screening can prevent colorectal cancer through the removal of adenomatous polyps. Most studies that have identified an increased risk for colorectal cancer in BRCA1/2 mutation carriers were in high-risk cancer families, while studies that found no association were conducted in specific populations and involved the analysis of founder mutations. A recent prospective study of 7015 women with a BRCA1 or BRCA2 mutation identified significant fivefold increased risk of colorectal cancer among BRCA1 mutation carriers younger than 50 years [standardized incidence ratio (SIR): 4.8; 95% CI: 2.2-9], but not in women with a BRCA2 mutation or in older women. Based on this evidence, women with BRCA1 mutations should be counseled about their increased risk for early-onset colorectal cancer, and offered colonoscopy at 3- to 5-year intervals between the ages of 40 and 50 years, and should follow population guidelines thereafter.
Assuntos
Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Genes BRCA1 , Genes BRCA2 , Predisposição Genética para Doença , Mutação , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Detecção Precoce de Câncer , Estudos de Associação Genética , Testes Genéticos , Humanos , Penetrância , Prevalência , RiscoRESUMO
Much of the observed familial clustering of breast and ovarian cancer cannot be explained by mutations in BRCA1 and BRCA2. Several other cancer susceptibility genes have been identified, but their value in routine clinical genetic testing is still unclear. Germline mutations in RAD51C have been identified in about 1% of hereditary breast and ovarian cancer families. RAD51C mutations are predominantly found in families with a history of ovarian cancer and are rare in families with a history of breast cancer alone. RAD51C is primarily an ovarian cancer susceptibility gene. A mutation is present in approximately 1% of unselected ovarian cancers. Among mutation carriers, the lifetime risk of ovarian cancer is approximately 9%. The average age at onset is approximately 60 years; this suggests that preventive oophorectomy can be delayed until after natural menopause. Under current guidelines, genetic testing for RAD51C is expected to have a limited impact on ovarian cancer incidence at a population level. This is because the penetrance is 9% to age 80; the great majority of families with mutations would be represented by a single case of ovarian cancer, these are potentially preventable through population screening but not through screening of established ovarian cancer families.
Assuntos
Proteínas de Ligação a DNA/genética , Mutação , Idoso , Neoplasias da Mama/genética , Análise Mutacional de DNA , Feminino , Efeito Fundador , Predisposição Genética para Doença , Testes Genéticos , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/genéticaRESUMO
Men with a BRCA2 mutation face substantial lifetime risks for the development of both breast and prostate cancer. A male who was initially diagnosed with breast cancer at the age of 32 was subsequently diagnosed at age 77 with both contralateral breast cancer and prostate cancer. He was found to be BRCA2 mutation carrier. The patient was treated with contralateral mastectomy, breast irradiation, prostate irradiation and adjuvant endocrine therapy. At age 83 he died of metastatic prostate cancer. Our case underscores the observation that BRCA2 mutation carriers are at risk for multiple cancers, including contralateral breast cancer, and illustrates the need for current practice recommendations for the early detection of breast and prostate cancer in men with BRCA2 mutations.
Assuntos
Proteína BRCA2/genética , Neoplasias da Mama Masculina/genética , Neoplasias da Próstata/genética , Idoso de 80 Anos ou mais , Mama/patologia , Mama/cirurgia , Neoplasias da Mama Masculina/radioterapia , Neoplasias da Mama Masculina/cirurgia , Predisposição Genética para Doença , Humanos , Masculino , Mastectomia , Próstata/patologia , Neoplasias da Próstata/radioterapia , Fatores de RiscoRESUMO
A number of genes other than BRCA1 and BRCA2 have been associated with breast cancer predisposition, and extended genetic testing panels have been proposed. It is of interest to establish the full spectrum of deleterious mutations in women with familial breast cancer.We performed whole-exome sequencing of 144 women with familial breast cancer and negative for 11 Polish founder mutations in BRCA1, CHEK2 and NBS1, and we evaluated the sequences of 12 known breast cancer susceptibility genes. A truncating mutation in a breast cancer gene was detected in 24 of 144 women (17%) with familial breast cancer. A BRCA2 mutation was detected in 12 cases, a (non-founder) BRCA1 mutation was detected in 5 cases, a PALB2 mutation was detected in 4 cases and an ATM mutation was detected in 2 cases. Polish women with familial breast cancer who are negative for founder mutations in BRCA1, CHEK2 and NBS1 should be fully screened for mutations in BRCA1, BRCA2 and PALB2. The PALB2 founder mutation c.509_519delGA should be included in the panel of Polish founder mutations.