BRCA1 and BRCA2 mutation status and cancer family history of Danish women affected with multifocal or bilateral breast cancer at a young age

INTRODUCTION—A small fraction of breast cancer is the result of germline mutations in the BRCA1 and BRCA2 cancer susceptibility genes. Mutation carriers frequently have a positive family history of breast and ovarian cancer, are often diagnosed at a young age, and may have a higher incidence of double or multiple primary breast tumours than breast cancer patients in general.
OBJECTIVES—To estimate the prevalence and spectrum of BRCA1 and BRCA2 mutations in young Danish patients affected with bilateral or multifocal breast cancer and to determine the relationship of mutation status to family history of cancer.
SUBJECTS—From the files of the Danish Breast Cancer Cooperative Group (DBCG), we selected 119 breast cancer patients diagnosed before the age of 46 years with either bilateral (n=59) or multifocal (n=61) disease.
METHODS—DNA from the subjects was screened for BRCA1 and BRCA2 mutations using single strand conformation analysis (SSCA) and the protein truncation test (PTT). Observed and expected cancer incidence in first degree relatives of the patients was estimated using data from the Danish Cancer Registry.
RESULTS—Twenty four mutation carriers were identified (20%), of whom 13 had a BRCA1 mutation and 11 carried a BRCA2 mutation. Two mutations in BRCA1 were found repeatedly in the material and accounted for seven of the 24 (29%) mutation carriers. The mutation frequency was about equal in patients with bilateral (22%) and multifocal breast cancer (18%). The incidence of breast and ovarian cancer was greatly increased in first degree relatives of BRCA1 and BRCA2 mutation carriers, but to a much lesser degree in relatives of non-carriers. An increased risk of cancer was also noted in brothers of non-carriers.
CONCLUSIONS—A relatively broad spectrum of germline mutations was observed in BRCA1 and BRCA2 and most of the mutations are present in other populations. Our results indicate that a diagnosis of bilateral and multifocal breast cancer is predictive of BRCA1 and BRCA2 mutation status, particularly when combined with information on the patients' age at diagnosis and family history of breast/ovarian cancer.


Keywords: breast cancer; mutations; BRCA1; BRCA2     

A survey of preventive measures among BRCA1 mutation carriers from Poland

Among women with a BRCA1 mutation, the lifetime risks of breast and ovarian cancer are elevated. Several measures for reducing cancer risk in carriers of BRCA1 mutations have been proposed, including prophylactic surgery and tamoxifen chemoprevention. It is not yet known to what extent women with mutations have adopted these various preventive measures. We surveyed 414 Polish women with a BRCA1 mutation who had received counseling about various preventive strategies. Each woman completed a survey for a minimum of 18 months after receiving her genetic result. A high proportion of women reported having had an oophorectomy to reduce breast and ovarian cancer risk (49.1%). In contrast, only 11% had taken tamoxifen and only 5% had undergone a preventive mastectomy. Most of the women (81%) had a screening mammogram during the follow-up period. Oral contraceptives and breastfeeding are believed to protect against ovarian cancer, but only 9% of women had taken the birth control pill for 3 years or more and 27% had breastfed for 1 year or more. In summary, approximately one-half of Polish women with a BRCA1 mutation had taken an active step to reduce their risk of breast cancer within 18 months of receiving a positive result. A greater effort should be made to promote breastfeeding and use of oral contraceptive as risk-reducing measures.     

Family history as a predictor of uptake of cancer preventive procedures by women with a BRCA1 or BRCA2 mutation

Women with a BRCA1 or BRCA2 mutation are at an elevated risk of developing breast and ovarian cancer; however, it is unclear to what extent family history influences the uptake of cancer prevention options.Women with a BRCA1/2 mutation completed a follow-up questionnaire that assessed uptake of cancer preventive options. The pedigree of each woman was reviewed, and information was recorded on cancers diagnosed in relatives. Five hundred and seventeen women were included in the study. Women with a sister with breast cancer were more likely to have a prophylactic mastectomy than those without a sister with breast cancer [odds ratios (OR) = 2.4, p = 0.003]. Uptake of prophylactic mastectomy was significantly lower in women with a mother with ovarian cancer compared with those whose mother did not have ovarian cancer (OR = 0.4, p = 0.01). Having a mother or sister with ovarian cancer significantly predicted the uptake of prophylactic oophorectomy (OR = 1.6, p = 0.04). Women with a BRCA2 mutation were less likely to have a prophylactic oophorectomy than those with a BRCA1 mutation (OR = 0.49, p = 0.0004). Among women with a BRCA1 or BRCA2 mutation, family history predicts the uptake of prophylactic mastectomy and prophylactic oophorectomy.     

Evaluation of a counselling protocol for predictive genetic testing for hereditary non-polyposis colorectal cancer

OBJECTIVES—To evaluate the feasibility of a reduced counselling programme for predictive genetic testing for hereditary non-polyposis colorectal cancer (HNPCC) in terms of counsellees' opinions on the extent and significance of genetic counselling and need for psychological support at different phases of the testing procedure.
DESIGN—Prospective follow up study with pre-test questionnaire assessment of background sociodemographic variables. The protocol comprised a pre-test counselling session, a period for reflection, and a test disclosure session. The outcome variables were studied by post-test questionnaires at one month and one year follow up.
SUBJECTS—Two hundred and seventy one high risk members of 36 families with HNPCC who attended both counselling sessions and completed the questionnaires.
RESULTS—The pre-test counselling was considered fairly or very useful by 89% of respondents and one post-test session was considered sufficient by over 80% of respondents at follow up. Fifty three percent would have used extra psychological support had it been offered with the counselling. On enquiry one year after receiving the test result, only 2% stated that the need for support was at its greatest at that time, while the majority (46%) reported that the need for support had been greatest at the moment of test disclosure.
CONCLUSIONS—A protocol that includes one comprehensive pre-test counselling session and a test disclosure session, supplemented with the option of professional psychological support, seems to be sufficient for both the educational and supportive needs of counsellees. Only a minority expressed a need for post-test follow up sessions, which suggests that, in this disorder, resources can be directed to the beneficial surveillance programmes rather than to extensive psychological support.


Keywords: predictive genetic testing; genetic counselling; HNPCC; hereditary non-polyposis colorectal cancer     

Racial differences in the incidence of BRCA1 and BRCA2 mutations in a cohort of early onset breast cancer patients: African American compared to white women

Purpose

To evaluate the frequency and distribution of BRCA1 and BRCA2 mutations in a cohort of young women with breast cancer and to compare the distribution of mutations as a function of race.

Methods

After IRB approved informed consent, 170 white women and 30 African American women with known breast cancer diagnosed at a young age (45 years or less) underwent complete sequencing of the BRCA1 and BRCA2 genes. Each cohort represented approximately 40% of women of the same ethnic background aged 45 years or younger in a breast cancer database.

Results

Of the 200 patients tested, 131 (65%) had wild type mutations, 34 (17%) had deleterious mutations, and 35 (18%) had variants of uncertain significance. There were no significant differences between the white and African American cohorts regarding the percentage of deleterious mutations (17% v 17%). However, most African American patients had mutations in BRCA2 (4/5, 80%), while most mutations in the white cohort were in BRCA1 (20/29, 69%). In addition, 46% of the African American women had variants of uncertain significance, compared to only 12% of the white cohort.

Conclusions

Young African American women with breast cancer have a similar frequency of deleterious mutations as white women, but have a significantly higher frequency of variants of uncertain significance. Review of these variants revealed that the majority were unlikely to be associated with disease risk or were likely to be polymorphisms. The implications for genetic testing and counselling in young women with breast cancer are discussed.     

Evaluation of the needs of spouses of female carriers of mutations in BRCA1 and BRCA2

The process of genetic testing involves the entire family, including spouses. The objective of this study was to measure the specific needs and to describe the experiences of spouses of women who received genetic counseling for a positive BRCA1/2 result. We surveyed 59 spouses of female mutation carriers. The mean length of relationships was 26 years (range: 2.5-50 years). All were supportive of their spouses' decision to undergo genetic testing and counselling. Four respondents stated that they wished that they had received additional support at the time of test disclosure and 20% felt that their wives had received inadequate support. One-quarter of the spouses believed that their relationship had changed because of genetic testing; most felt that they had become closer to their wives. Husbands were most concerned about the risk of their wife dying of cancer (43%), followed by the risk of their spouse developing cancer (19%) and the risk that their children would test positive for the BRCA mutation (14%). Distress levels, measured by the Impact of Event scale, suggest that few spouses were experiencing clinical levels of distress.     

Predictive genetic testing in children and adults: a study of emotional impact

AIM—To determine whether, following predictive genetic testing for familial adenomatous polyposis (FAP), children or adults receiving positive results experience clinically significant levels of anxiety or depression, and whether children receiving positive results experience higher levels of anxiety or depression than adults receiving positive results.
DESIGN—Two studies, one cross sectional and one prospective.
SAMPLE—208 unaffected subjects (148 adults and 60 children) at risk for FAP who have undergone genetic testing since 1990.
MAIN MEASURES—Dependent variables: anxiety, depression; independent variables: test results, demographic measures, psychological resources (optimism, self-esteem).
RESULTS—Study 1. In children receiving positive results, mean scores for anxiety and depression were within the normal range. There was a trend for children receiving positive results to be more anxious and depressed than those receiving negative results. In adults, mean scores for anxiety were within the normal range for those receiving negative results, but were in the clinical range for those receiving positive results, with 43% (95% CI 23-65) of the latter having scores in this range. Regardless of test result, adults were more likely to be clinically anxious if they were low in optimism or self-esteem. Children receiving positive or negative results did not experience greater anxiety or depression than adults. Study 2. For children receiving a positive test result, mean scores for anxiety, depression, and self-esteem were unchanged over the year following the result, while mean anxiety scores decreased and self-esteem increased after receipt of a negative test result over the same period of time.
CONCLUSION—Children, as a group, did not show clinically significant distress over the first year following predictive genetic testing. Adults were more likely to be clinically anxious if they received a positive result or were low in optimism or self-esteem, with interacting effects. The association between anxiety, self-esteem, and optimism suggests that counselling should be targeted, not only at those with positive test results, but also at those low in psychological resources.


Keywords: genetic testing; children; familial adenomatous polyposis; emotional impact     

Efficacy of a touchscreen computer based family cancer history questionnaire and subsequent cancer risk assessment

OBJECTIVE—A computer based touchscreen family cancer history questionnaire was developed and implemented to facilitate the provision of cancer risk assessments for the ambulatory and outpatient populations of a free standing cancer hospital.
METHODS—A questionnaire consisting of a series of branched point decision making screens was developed which enables the participant to enter demographic data, personal cancer history, and cancer histories for first and second degree relatives. A freestanding touchscreen computer kiosk system was used to place the questionnaire in public areas of the cancer hospital and clinic. Genetic professionals analysed the data received, using published criteria, and provided a basic cancer risk assessment and surveillance recommendations within 10 business days. A survey was completed by a small random group of users (n=59) three to six months after receipt of their risk assessment.
RESULTS—After 11 months, 1440 people had entered information and received a written communication. Only 2% of completed questionnaires contained insufficient information to provide a basic risk assessment. Of the small group of participants surveyed, almost all (95%) felt "very comfortable" using the system, 93% remembered receiving the risk assessment letter when queried three to six months later, 42% felt their perceptions about cancer risk had changed, and 20% had made changes in their or their family's cancer surveillance practices.
CONCLUSION—The touchscreen computer family history questionnaire allows easy collection of family history information, provision of risk assessments to a broad population, and promotes increased awareness of familial risk and appropriate surveillance.


Keywords: genetic counselling; risk assessment; computers; medical informatics     

Systematic review of the empirical investigation of resources to support decision-making regarding BRCA1 and BRCA2 genetic testing in women with breast cancer

Objective

Identify existing resources developed and/or evaluated empirically in the published literature designed to support women with breast cancer making decisions regarding genetic testing for BRCA1/2 mutations.

BRCA1 and BRCA2 Germline Mutations Screening in Algerian Breast/Ovarian Cancer Families

Background: Breast cancer is the leading cause of cancer death in women in Algeria. The contribution of BRCA1 and BRCA2 mutations to hereditary breast/ovarian cancer in Algerian population is largely unknown. Here, we describe analysis of BRCA1 and BRCA2 genes in 86 individuals from 70 families from an Algerian cohort with a personal and family history suggestive of genetic predisposition to breast cancer. Methods: The approach used is based on BRCA1 and BRCA2 mutations screening by High-Resolution Melting (HRM) curve analysis followed by direct sequencing. All samples for which no pathogenic mutation was found were analyzed by MLPA for large deletions or duplications. Results: Three distinct pathogenic mutations c.83_84delTG, c.181T>G, c.798_799delTT and two large rearrangements involving deletion of exon 2 and exon 8 respectively, were detected in BRCA1 gene. Moreover 17 unclassified variants and polymorphisms were detected in BRCA1 gene (6 described for the first time). Two pathogenic mutations, c.1310_1313delAAGA and c.5722_5723delCT and 40 unclassified variants and polymorphisms (14 never described before) were identified in BRCA2 gene. Conclusions: For the first time, we used HRM and MLPA to identify BRCA1 and BRCA2 mutations in Algerian patients with a personal and family history suggestive of genetic predisposition to breast cancer. The implications of these new findings in regard to genetic testing and counseling are substantial for the Algerian population.     

Development and testing of a decision aid for breast cancer prevention for women with a BRCA1 or BRCA2 mutation

For women who carry a mutation in BRCA1 or BRCA2, the risk of breast cancer is up to 87% by the age of 70. There are options available to reduce the risk of breast cancer; however, each option has both risks and benefits, which makes decision making difficult. The objective is to develop and pilot test a decision aid for breast cancer prevention for women with a BRCA1 or BRCA2 mutation. The decision aid was developed and evaluated in three stages. In the first stage, the decision aid was developed and reviewed by cancer genetics experts. The second stage was a review of the decision aid by women with a BRCA1 or BRCA2 mutation for acceptability and feasibility. The final stage was a pre-test--post-test evaluation of the decision aid. Twenty-one women completed the pre-test questionnaire and 20 completed the post-test questionnaire. After using the decision aid, there was a significant decline in mean decisional conflict scores (p = 0.001), a significant improvement in knowledge scores (p = 0.004), and fewer women uncertain about prophylactic mastectomy (p = 0.003) and prophylactic oophorectomy (p = 0.009). Use of the decision aid decreased decisional conflict to levels suggestive of implementation of a decision. In addition, knowledge levels increased and choice predisposition changed with fewer women being uncertain about each option. This has significant clinical implications as it implies that with greater uptake of cancer prevention options by women with a BRCA1 or BRCA2 mutation, fewer women will develop and/or die of hereditary breast cancer.     

Prevalence of BRCA1 gene mutation in breast cancer patients in Guangxi,China

Objective: The prevalence of breast cancer susceptibility gene 1 mutation in breast cancer patients of south China has not been well revealed. This study was to invest the prevalence of BRCA1 gene mutation in breast cancer patients in Guangxi, China, and to try reflecting its relevance in genetic counseling of breast cancer. Methods: In this study, 463 breast cancer patients and 30 healthy women (control group) were involved. Entire sequence and splicing sites of BRCA1 genes were detected by PCR-DNA sequencing. Results: About 8.9% (41/463) patients were with 22 BRCA1 mutations (all in exon 10). The average hospitalized age of BRCA1-associated breast cancer cases was significantly younger (t = -2.965, P = 0.003). The nuclear grade (U = 2321.0, P = 0.030), ER (U = 4343.5, P = 0.041) and CerbB-2 (U = 3894.0, P = 0.038) expression levels, and triple negative breast cancer diagnosing rate (χ² = 4.719, P = 0.03) were disclosed more in BRCA1-associated patients. Conclusions: The four most frequent BRCA1 mutation (2798 T > C, 3971 G > A, 3971 G > A and 624 C > T) found in female breast cancer cases in Guangxi are all located in exon 10. BRCA1-associated breast cancer cases have earlier onset age, higher nuclear grade and negative ER and CerbB-2 expression.     

Uptake and timing of bilateral prophylactic salpingo-oophorectomy among BRCA1 and BRCA2 mutation carriers

PurposeTo evaluate prophylactic salpingo-oophorectomy uptake and timing among BRCA1/2 mutation carriers in a cancer risk assessment program.MethodsClinical records of female BRCA1/2 mutation carriers who received cancer genetic counseling between 1996 and 2003 were reviewed to determine the completion and the timing of prophylactic salpingo-oophorectomy. Logistic regression models evaluated associations between subject characteristics and surgery. Survival analysis methods were used to estimate the distribution of time to surgery.ResultsAmong 88 women, 70% underwent prophylactic salpingo-oophorectomy. Prophylactic salpingo-oophorectomy was associated with older age, white race, having children, and a family history of ovarian cancer. Many women waited more than 12 months to undergo surgery and some delayed by several years. Younger age and not having children were associated with delays to surgery.ConclusionProphylactic salpingo-ooporectomy is an acceptable risk reduction measure for many BRCA1/2 mutation carriers. Some women make this decision many years after genetic testing. Continued discussion of the risks and benefits of risk reduction options may facilitate the uptake of recommended risk reduction interventions among BRCA mutation carriers.     

Risks of breast and ovarian cancer for women harboring pathogenic missense variants in BRCA1 and BRCA2 compared with those harboring protein truncating variants

PurposeGermline genetic testing for BRCA1 and BRCA2 variants has been a part of clinical practice for >2 decades. However, no studies have compared the cancer risks associated with missense pathogenic variants (PVs) with those associated with protein truncating (PTC) variants.MethodsWe collected 582 informative pedigrees segregating 1 of 28 missense PVs in BRCA1 and 153 pedigrees segregating 1 of 12 missense PVs in BRCA2. We analyzed 324 pedigrees with PTC variants in BRCA1 and 214 pedigrees with PTC variants in BRCA2. Cancer risks were estimated using modified segregation analysis.ResultsEstimated breast cancer risks were markedly lower for women aged >50 years carrying BRCA1 missense PVs than for the women carrying BRCA1 PTC variants (hazard ratio [HR] = 3.9 [2.4-6.2] for PVs vs 12.8 [5.7-28.7] for PTC variants; P = .01), particularly for missense PVs in the BRCA1 C-terminal domain (HR = 2.8 [1.4-5.6]; P = .005). In case of BRCA2, for women aged >50 years, the HR was 3.9 (2.0-7.2) for those heterozygous for missense PVs compared with 7.0 (3.3-14.7) for those harboring PTC variants. BRCA1 p.[Cys64Arg] and BRCA2 p.[Trp2626Cys] were associated with particularly low risks of breast cancer compared with other PVs.ConclusionThese results have important implications for the counseling of at-risk women who harbor missense PVs in the BRCA1/2 genes.     

Breast and ovarian cancer risk perception after prophylactic salpingo-oophorectomy due to an inherited mutation in the BRCA1 or BRCA2 gene

It is often recommended that women who carry a mutation in the BRCA1 or BRCA2 gene have their ovaries and fallopian tubes removed to reduce their risk of gynecologic cancer. The aim of this study was to evaluate women's perception of their risk of breast and ovarian cancer before and after prophylactic salpingo-oophorectomy. We surveyed 127 women who carry a BRCA1 or BRCA2 mutation and who underwent prophylactic salpingo-oophorectomy at the University Health Network, Toronto. Subjects were asked to estimate their risks of breast and ovarian cancer before and after surgery. Their perceived risks of cancers were then compared with published risks, based on their mutation status. BRCA1 carriers estimated their risk of breast cancer risk to be, on average, 69% before surgery and 41% after surgery. They estimated their risk of ovarian cancer to be 55% before surgery and 11% after surgery. BRCA2 carriers estimated their risk of breast cancer to be 69% prior to surgery and 45% after surgery and their perceived risk of ovarian cancer to be 43% before surgery and 8% after surgery. Compared with published risk figures, the perceived risk of ovarian cancer before prophylactic salpingo-oophorectomy was overestimated by 47% of BRCA1 mutation carriers and by 61% of BRCA2 mutation carriers. Most women who have undergone genetic counseling and subsequently choose prophylactic salpingo-oophorectomy accurately perceive their risk of breast cancer. However, in this study, many women overestimated their risk of ovarian cancer, particularly women who carry a BRCA2 mutation.     

Peutz-Jeghers families unlinked to STK11/LKB1 gene mutations are highly predisposed to primitive biliary adenocarcinoma

INTRODUCTION—Germline mutations of the STK11/LKB1 tumour suppressor gene (19p13.3) are responsible for Peutz-Jeghers syndrome (PJS), a rare genetic disorder, which is dominantly inherited. In addition to the typical hamartomatous gastrointestinal polyps and perioral pigmented lesions, PJS is also associated with the development of tumours in various sites. No specific follow up has yet been evaluated for gene carriers. Furthermore, genetic heterogeneity has been reported, which makes genetic counselling difficult.
METHODS—We report here the analysis of the STK11/LKB1 locus in a series of 34 PJS families, combining the search for mutations and rearrangements in the coding sequence, allele specific expression tests, and linkage studies.
RESULTS—Germline deleterious mutation of the STK11/LKB1 gene were identified in 70% of cases. The hypothesis of a second PJS locus was reinforced and PJS families could be divided into two groups on the basis of the presence or absence of an identified STK11/LKB1 alteration. Analysis of clinical data indicates that the cancer associated risk is markedly different in the two groups. PJS patients with no identified STK11/LKB1 mutation are at major risk for proximal biliary adenocarcinoma, an infrequent tumour in the general population.
CONCLUSION—Up to 30% of PJS patients are caused by mutation in an unidentified gene that confers high susceptibility to cancer development.


Keywords: Peutz-Jeghers disease; genetic heterogeneity; cancer predisposition; risk estimation     

De novo recurrent germline mutation of the BRCA2 gene in a patient with early onset breast cancer

Germline mutations in either of the two major breast cancer predisposition genes, BRCA1 and BRCA2, account for a significant proportion of hereditary breast/ovarian cancer. Identification of breast cancer patients carrying mutations of these genes is primarily based on a positive family history of breast/ovarian cancer or early onset of the disease or both. In the course of mutation screening of the BRCA1 and BRCA2 genes in a hospital based series of patients with risk factors for hereditary breast/ovarian cancer, we identified a germline mutation in the BRCA2 gene (3034del4) in a patient with early onset breast cancer and no strong family history of the disease. Subsequent molecular analysis in her parents showed that neither of them carried the mutation. Paternity was confirmed using a set of highly polymorphic markers, showing that the proband carried a de novo germline mutation in the BRCA2 gene. Interestingly, 3034del4 is a recurrent mutation occurring in a putative mutation prone region of the BRCA2 gene. Our study presents the first case in which a de novo germline mutation in the BRCA2 gene has been identified, and supports previous results of haplotype studies, confirming that the 3034del4 mutation has multiple independent origins.


Keywords: breast cancer; BRCA2 gene; de novo mutation     

Uptake Rate of Risk-Reducing Salpingo-Oophorectomy and Surgical Outcomes of Female Germline BRCA1/2 Mutation Carriers: A Retrospective Cohort Study

PurposeThis study investigated the uptake rate of risk-reducing salpingo-oophorectomy (RRSO) and surgical outcomes of germline BRCA1/2 mutation carriers at Seoul National University Hospital (SNUH).Materials and MethodsWe examined the records of 824 women who underwent germline BRCA1/2 gene testing at SNUH between 2005 and 2020. Among them, we identified women with a pathogenic mutation on either the BRCA1 or the BRCA2 gene, and excluded ovarian cancer patients. Characteristics of participants who underwent RRSO (RRSO group) were compared to those who did not (non-RRSO group). Surgical outcomes and pathologic results were investigated in the RRSO group.ResultsThere were 117 BRCA1/2 mutation carriers included in the analysis. The uptake rate of RRSO was 70.1% (82/117). Older age (mean: 48.8 years vs. 42.1 years; p=0.002) and higher employment rate (65.9% vs. 14.3%; p<0.001) were observed in the RRSO group compared to the non-RRSO group. However, no differences in other factors, such as personal and family history of breast cancer, were observed between the two groups. In the RRSO group, the median time interval between the genetic test and RRSO was 10.0 months, and there were three (3.7%) incidental cases of high-grade serous carcinoma. However, one patient in the non-RRSO group developed primary peritoneal cancer after 103.8 months of surveillance.ConclusionThe uptake rate of RRSO in BRCA1/2 mutation carriers was about 70%. Considering incidental cancer cases in women without abnormal findings on preoperative evaluation, BRCA1/2-mutated women might refrain from the delayed implementation of RRSO after the genetic test.     

Patient satisfaction and cancer‐related distress among unselected Jewish women undergoing genetic testing for BRCA1 and BRCA2

Metcalfe KA, Poll A, Llacuachaqui M, Nanda S, Tulman A, Mian N, Sun P, Narod SA. Patient satisfaction and cancer‐related distress among unselected Jewish women undergoing genetic testing for BRCA1 and BRCA2. It is not known to what extent participation in a genetic testing program for BRCA1 and BRCA2, which does not include an extensive pre‐test counselling session, influences cancer‐related distress, cancer risk perception and patient satisfaction. Unselected Jewish women in Ontario were offered genetic testing for three common Jewish BRCA mutations. Before testing and 1‐year post‐testing, the women completed questionnaires which assessed cancer‐related distress, cancer risk perception, and satisfaction. A total of 2080 women enrolled in the study; of these, 1516 (73%) completed a 1‐year follow‐up questionnaire. In women with a BRCA mutation, the mean breast cancer risk perception increased from 41.1% to 59.6% after receiving a positive genetic test result (p = 0.002). Among non‐carriers, breast cancer risk perception decreased slightly, from 35.8% to 33.5% (p = 0.08). The mean level of cancer‐related distress increased significantly for women with a BRCA mutation, but did not change in women without a mutation; 92.8% expressed satisfaction with the testing process. The results of this study suggest that the majority of Jewish women who took part in population genetic screening for BRCA1 and BRCA2 were satisfied with the delivery of genetic testing and would recommend testing to other Jewish women. However, women with a BRCA mutation experienced increased levels of cancer‐related distress.     

Molecular analysis of the APC gene in 205 families: extended genotype-phenotype correlations in FAP and evidence for the role of APC amino acid changes in colorectal cancer predisposition

BACKGROUND/AIMS—The development of colorectal cancer and a variable range of extracolonic manifestations in familial adenomatous polyposis (FAP) is the result of the dominant inheritance of adenomatous polyposis coli (APC) gene mutations. In this study, direct mutation analysis of the APC gene was performed to determine genotype-phenotype correlations for nine extracolonic manifestations and to investigate the incidence of APC mutations in non-FAP colorectal cancer.
METHODS—The APC gene was analysed in 190 unrelated FAP and 15 non-FAP colorectal cancer patients using denaturing gradient gel electrophoresis, the protein truncation test, and direct sequencing.
RESULTS—Chain terminating signals were only identified in patients belonging to the FAP group (105 patients). Amino acid changes were identified in four patients, three of whom belonged to the non-FAP group of colorectal cancer patients. Genotype-phenotype correlations identified significant differences in the nature of certain extracolonic manifestations in FAP patients belonging to three mutation subgroups.
CONCLUSIONS—Extended genotypephenotype correlations made in this study may have the potential to determine the most appropriate surveillance and prophylactic treatment regimens for those patients with mutations associated with life threatening conditions. This study also provided evidence for the pathological nature of amino acid changes in APC associated with both FAP and non-FAP colorectal cancer patients.


Keywords: familial adenomatous polyposis; genotype-phenotype; familial colorectal cancer