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Introduction: Height, body mass index (BMI), and weight gain are associated with breast cancer risk in the general population. It is unclear whether these associations also exist for carriers of pathogenic variants in the BRCA1 or BRCA2 genes., Patients and Methods: An international pooled cohort of 8091 BRCA1/2 variant carriers was used for retrospective and prospective analyses separately for premenopausal and postmenopausal women. Cox regression was used to estimate breast cancer risk associations with height, BMI, and weight change., Results: In the retrospective analysis, taller height was associated with risk of premenopausal breast cancer for BRCA2 variant carriers (HR 1.20 per 10 cm increase, 95% CI 1.04-1.38). Higher young-adult BMI was associated with lower premenopausal breast cancer risk for both BRCA1 (HR 0.75 per 5 kg/m 2 , 95% CI 0.66-0.84) and BRCA2 (HR 0.76, 95% CI 0.65-0.89) variant carriers in the retrospective analysis, with consistent, though not statistically significant, findings from the prospective analysis. In the prospective analysis, higher BMI and adult weight gain were associated with higher postmenopausal breast cancer risk for BRCA1 carriers (HR 1.20 per 5 kg/m 2 , 95% CI 1.02-1.42; and HR 1.10 per 5 kg weight gain, 95% CI 1.01-1.19, respectively)., Conclusion: Anthropometric measures are associated with breast cancer risk for BRCA1 and BRCA2 variant carriers, with relative risk estimates that are generally consistent with those for women from the general population., (© 2023. The Author(s).)

Objective: Genetic counseling in at-risk families is known to improve cancer prevention. Our study aimed to determine the rate of uptake of genetic counseling among adult children of BRCA1/2 mutation carriers and to identify the potential psychosocial factors associated with uptake of genetic counseling., Methods: A self-reported questionnaire was mailed to 328 BRCA1/2 mutation carriers 10 years after BRCA1/2 test disclosure. Of the 233 carriers who returned the questionnaire (response rate = 71%), 135 reported having children over age 18 years and were therefore included in the analysis. Generalized estimating equations models were used to identify the factors associated with uptake of genetic counseling among adult children of mutation carriers., Results: Data were gathered for a total of 296 children (46% male, 54% female). The vast majority were informed about the familial mutation (90.9%) and 113 (38%; 95% CI, 32%-44%) underwent genetic counseling. This percentage exceeded 80% in women over 40 years. In the multivariate model, female sex, advanced age, mutation in the father, diagnosis of cancer in the mutation-carrying parent after genetic testing, and good family relationships were all factors associated with higher uptake of genetic counseling., Conclusions: Adult children of BRCA1/2 mutation carriers in France do not undergo genetic counseling sufficiently often. Further studies should be conducted on the psychosocial factors that hinder the uptake of genetic counseling among adult children of BRCA1/2 mutation carriers., (© 2019 John Wiley & Sons, Ltd.)

Importance: The clinical management of BRCA1 and BRCA2 mutation carriers requires accurate, prospective cancer risk estimates., Objectives: To estimate age-specific risks of breast, ovarian, and contralateral breast cancer for mutation carriers and to evaluate risk modification by family cancer history and mutation location., Design, Setting, and Participants: Prospective cohort study of 6036 BRCA1 and 3820 BRCA2 female carriers (5046 unaffected and 4810 with breast or ovarian cancer or both at baseline) recruited in 1997-2011 through the International BRCA1/2 Carrier Cohort Study, the Breast Cancer Family Registry and the Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer, with ascertainment through family clinics (94%) and population-based studies (6%). The majority were from large national studies in the United Kingdom (EMBRACE), the Netherlands (HEBON), and France (GENEPSO). Follow-up ended December 2013; median follow-up was 5 years., Exposures: BRCA1/2 mutations, family cancer history, and mutation location., Main Outcomes and Measures: Annual incidences, standardized incidence ratios, and cumulative risks of breast, ovarian, and contralateral breast cancer., Results: Among 3886 women (median age, 38 years; interquartile range [IQR], 30-46 years) eligible for the breast cancer analysis, 5066 women (median age, 38 years; IQR, 31-47 years) eligible for the ovarian cancer analysis, and 2213 women (median age, 47 years; IQR, 40-55 years) eligible for the contralateral breast cancer analysis, 426 were diagnosed with breast cancer, 109 with ovarian cancer, and 245 with contralateral breast cancer during follow-up. The cumulative breast cancer risk to age 80 years was 72% (95% CI, 65%-79%) for BRCA1 and 69% (95% CI, 61%-77%) for BRCA2 carriers. Breast cancer incidences increased rapidly in early adulthood until ages 30 to 40 years for BRCA1 and until ages 40 to 50 years for BRCA2 carriers, then remained at a similar, constant incidence (20-30 per 1000 person-years) until age 80 years. The cumulative ovarian cancer risk to age 80 years was 44% (95% CI, 36%-53%) for BRCA1 and 17% (95% CI, 11%-25%) for BRCA2 carriers. For contralateral breast cancer, the cumulative risk 20 years after breast cancer diagnosis was 40% (95% CI, 35%-45%) for BRCA1 and 26% (95% CI, 20%-33%) for BRCA2 carriers (hazard ratio [HR] for comparing BRCA2 vs BRCA1, 0.62; 95% CI, 0.47-0.82; P=.001 for difference). Breast cancer risk increased with increasing number of first- and second-degree relatives diagnosed as having breast cancer for both BRCA1 (HR for ≥2 vs 0 affected relatives, 1.99; 95% CI, 1.41-2.82; P<.001 for trend) and BRCA2 carriers (HR, 1.91; 95% CI, 1.08-3.37; P=.02 for trend). Breast cancer risk was higher if mutations were located outside vs within the regions bounded by positions c.2282-c.4071 in BRCA1 (HR, 1.46; 95% CI, 1.11-1.93; P=.007) and c.2831-c.6401 in BRCA2 (HR, 1.93; 95% CI, 1.36-2.74; P<.001)., Conclusions and Relevance: These findings provide estimates of cancer risk based on BRCA1 and BRCA2 mutation carrier status using prospective data collection and demonstrate the potential importance of family history and mutation location in risk assessment.

Background: Most BRCA1 or BRCA2 mutation carriers have inherited a single (heterozygous) mutation. Transheterozygotes (TH) who have inherited deleterious mutations in both BRCA1 and BRCA2 are rare, and the consequences of transheterozygosity are poorly understood., Methods: From 32,295 female BRCA1/2 mutation carriers, we identified 93 TH (0.3 %). "Cases" were defined as TH, and "controls" were single mutations at BRCA1 (SH1) or BRCA2 (SH2). Matched SH1 "controls" carried a BRCA1 mutation found in the TH "case". Matched SH2 "controls" carried a BRCA2 mutation found in the TH "case". After matching the TH carriers with SH1 or SH2, 91 TH were matched to 9316 SH1, and 89 TH were matched to 3370 SH2., Results: The majority of TH (45.2 %) involved the three common Jewish mutations. TH were more likely than SH1 and SH2 women to have been ever diagnosed with breast cancer (BC; p = 0.002). TH were more likely to be diagnosed with ovarian cancer (OC) than SH2 (p = 0.017), but not SH1. Age at BC diagnosis was the same in TH vs. SH1 (p = 0.231), but was on average 4.5 years younger in TH than in SH2 (p < 0.001). BC in TH was more likely to be estrogen receptor (ER) positive (p = 0.010) or progesterone receptor (PR) positive (p = 0.013) than in SH1, but less likely to be ER positive (p < 0.001) or PR positive (p = 0.012) than SH2. Among 15 tumors from TH patients, there was no clear pattern of loss of heterozygosity (LOH) for BRCA1 or BRCA2 in either BC or OC., Conclusions: Our observations suggest that clinical TH phenotypes resemble SH1. However, TH breast tumor marker characteristics are phenotypically intermediate to SH1 and SH2.

Introduction: Individuals carrying pathogenic mutations in the BRCA1 and BRCA2 genes have a high lifetime risk of breast cancer. BRCA1 and BRCA2 are involved in DNA double-strand break repair, DNA alterations that can be caused by exposure to reactive oxygen species, a main source of which are mitochondria. Mitochondrial genome variations affect electron transport chain efficiency and reactive oxygen species production. Individuals with different mitochondrial haplogroups differ in their metabolism and sensitivity to oxidative stress. Variability in mitochondrial genetic background can alter reactive oxygen species production, leading to cancer risk. In the present study, we tested the hypothesis that mitochondrial haplogroups modify breast cancer risk in BRCA1/2 mutation carriers., Methods: We genotyped 22,214 (11,421 affected, 10,793 unaffected) mutation carriers belonging to the Consortium of Investigators of Modifiers of BRCA1/2 for 129 mitochondrial polymorphisms using the iCOGS array. Haplogroup inference and association detection were performed using a phylogenetic approach. ALTree was applied to explore the reference mitochondrial evolutionary tree and detect subclades enriched in affected or unaffected individuals., Results: We discovered that subclade T1a1 was depleted in affected BRCA2 mutation carriers compared with the rest of clade T (hazard ratio (HR) = 0.55; 95% confidence interval (CI), 0.34 to 0.88; P = 0.01). Compared with the most frequent haplogroup in the general population (that is, H and T clades), the T1a1 haplogroup has a HR of 0.62 (95% CI, 0.40 to 0.95; P = 0.03). We also identified three potential susceptibility loci, including G13708A/rs28359178, which has demonstrated an inverse association with familial breast cancer risk., Conclusions: This study illustrates how original approaches such as the phylogeny-based method we used can empower classical molecular epidemiological studies aimed at identifying association or risk modification effects.

Importance: Limited information about the relationship between specific mutations in BRCA1 or BRCA2 (BRCA1/2) and cancer risk exists., Objective: To identify mutation-specific cancer risks for carriers of BRCA1/2., Design, Setting, and Participants: Observational study of women who were ascertained between 1937 and 2011 (median, 1999) and found to carry disease-associated BRCA1 or BRCA2 mutations. The international sample comprised 19,581 carriers of BRCA1 mutations and 11,900 carriers of BRCA2 mutations from 55 centers in 33 countries on 6 continents. We estimated hazard ratios for breast and ovarian cancer based on mutation type, function, and nucleotide position. We also estimated RHR, the ratio of breast vs ovarian cancer hazard ratios. A value of RHR greater than 1 indicated elevated breast cancer risk; a value of RHR less than 1 indicated elevated ovarian cancer risk., Exposures: Mutations of BRCA1 or BRCA2., Main Outcomes and Measures: Breast and ovarian cancer risks., Results: Among BRCA1 mutation carriers, 9052 women (46%) were diagnosed with breast cancer, 2317 (12%) with ovarian cancer, 1041 (5%) with breast and ovarian cancer, and 7171 (37%) without cancer. Among BRCA2 mutation carriers, 6180 women (52%) were diagnosed with breast cancer, 682 (6%) with ovarian cancer, 272 (2%) with breast and ovarian cancer, and 4766 (40%) without cancer. In BRCA1, we identified 3 breast cancer cluster regions (BCCRs) located at c.179 to c.505 (BCCR1; RHR = 1.46; 95% CI, 1.22-1.74; P = 2 × 10(-6)), c.4328 to c.4945 (BCCR2; RHR = 1.34; 95% CI, 1.01-1.78; P = .04), and c. 5261 to c.5563 (BCCR2', RHR = 1.38; 95% CI, 1.22-1.55; P = 6 × 10(-9)). We also identified an ovarian cancer cluster region (OCCR) from c.1380 to c.4062 (approximately exon 11) with RHR = 0.62 (95% CI, 0.56-0.70; P = 9 × 10(-17)). In BRCA2, we observed multiple BCCRs spanning c.1 to c.596 (BCCR1; RHR = 1.71; 95% CI, 1.06-2.78; P = .03), c.772 to c.1806 (BCCR1'; RHR = 1.63; 95% CI, 1.10-2.40; P = .01), and c.7394 to c.8904 (BCCR2; RHR = 2.31; 95% CI, 1.69-3.16; P = .00002). We also identified 3 OCCRs: the first (OCCR1) spanned c.3249 to c.5681 that was adjacent to c.5946delT (6174delT; RHR = 0.51; 95% CI, 0.44-0.60; P = 6 × 10(-17)). The second OCCR spanned c.6645 to c.7471 (OCCR2; RHR = 0.57; 95% CI, 0.41-0.80; P = .001). Mutations conferring nonsense-mediated decay were associated with differential breast or ovarian cancer risks and an earlier age of breast cancer diagnosis for both BRCA1 and BRCA2 mutation carriers., Conclusions and Relevance: Breast and ovarian cancer risks varied by type and location of BRCA1/2 mutations. With appropriate validation, these data may have implications for risk assessment and cancer prevention decision making for carriers of BRCA1 and BRCA2 mutations.

While interplay between BRCA1 and AURKA-RHAMM-TPX2-TUBG1 regulates mammary epithelial polarization, common genetic variation in HMMR (gene product RHAMM) may be associated with risk of breast cancer in BRCA1 mutation carriers. Following on these observations, we further assessed the link between the AURKA-HMMR-TPX2-TUBG1 functional module and risk of breast cancer in BRCA1 or BRCA2 mutation carriers. Forty-one single nucleotide polymorphisms (SNPs) were genotyped in 15,252 BRCA1 and 8,211 BRCA2 mutation carriers and subsequently analyzed using a retrospective likelihood approach. The association of HMMR rs299290 with breast cancer risk in BRCA1 mutation carriers was confirmed: per-allele hazard ratio (HR) = 1.10, 95% confidence interval (CI) 1.04-1.15, p = 1.9 x 10(-4) (false discovery rate (FDR)-adjusted p = 0.043). Variation in CSTF1, located next to AURKA, was also found to be associated with breast cancer risk in BRCA2 mutation carriers: rs2426618 per-allele HR = 1.10, 95% CI 1.03-1.16, p = 0.005 (FDR-adjusted p = 0.045). Assessment of pairwise interactions provided suggestions (FDR-adjusted pinteraction values > 0.05) for deviations from the multiplicative model for rs299290 and CSTF1 rs6064391, and rs299290 and TUBG1 rs11649877 in both BRCA1 and BRCA2 mutation carriers. Following these suggestions, the expression of HMMR and AURKA or TUBG1 in sporadic breast tumors was found to potentially interact, influencing patients' survival. Together, the results of this study support the hypothesis of a causative link between altered function of AURKA-HMMR-TPX2-TUBG1 and breast carcinogenesis in BRCA1/2 mutation carriers.

Purpose: This study aimed to measure patients' smoking patterns for 5 years after BRCA1/2 test result disclosure., Methods: A national cohort consisting of 621 French cancer-free women from families with BRCA1/2 mutations (mean age (SD): 40.5 years (11.5 years)) were included from December 1999 to January 2006, before disclosure of genetic test results, and followed for 5 years. They completed self-administered questionnaires about their cigarette smoking behaviors before receiving their test results (baseline) and 6, 12, 24, and 60 months after disclosure. Multivariate statistical analyses of the changes in participants' smoking behaviors were performed using a zero-inflated Poisson mixed model., Results: Baseline smoking was found to depend on age, educational level, marital status, alcohol consumption, body mass index, and cancer risk perception. The zero-inflated part of the model showed the occurrence of no significant changes in the percentage of smokers during the 5 years after disclosure of the BRCA1/2 test results; however, daily smoking among BRCA1/2 carriers decreased significantly compared with that of noncarriers (adjusted hazard ratio = 0.83; (95% confidence interval: 0.69-0.99); P = 0.04) after adjusting for baseline smoking behavior., Conclusion: It would be worth investigating the possibility of counseling women during the genetic testing process about the multiple risk factors involved in cancer, such as genetic and lifestyle factors.

Objective: The aim of this study is to prospectively determine the factors contributing to whether unaffected women from BRCA1/2 families reported that clinicians proposed psychological consultations and that they had attended these consultations during the genetic testing process., Methods: A prospective study was performed on a national cohort, using self-administered questionnaires to determine the rates of proposal and use of psychological services at the time of BRCA1/2 test result disclosure (N = 533) and during the first year after disclosure (N = 478) among unaffected French women from BRCA1/2 families who had undergone genetic testing for BRCA1/2. Multivariate adjustment was carried out using logistic regression models fitted using generalized estimation equations, with the genetic testing centre as the clustering variable., Results: At the time of BRCA1/2 test result disclosure, a psychological consultation was proposed by cancer geneticists to 72% and 32% of the carriers (N = 232) and noncarriers (N = 301), respectively (p < 0.001). One year after disclosure, 21% of the carriers had consulted a psychologist, versus 9% of the noncarriers (p < 0.001). Both the proposal and the uptake depended on the women's BRCA1/2 mutation carrier status (proposal adjusted odds ratio (AOR): 4.9; 95% confidence interval (CI) 3.4-7.2; uptake AOR: 2.2; 95% CI 1.2-4.0), their level of education (proposal AOR: 1.7; 95% CI 1.1-2.7; uptake AOR: 4.5; 95% CI 1.7-12.1) and the distress they experienced about their genetic test results (proposal AOR: 1.02; 95% CI 1.01-1.03; uptake AOR: 1.04; 95% CI 1.02-1.06) CONCLUSIONS: Determinants of the proposal/uptake of psychological consultations in the BRCA1/2 testing process highlight the need for inventive strategies to reach the different types of women's profiles., (Copyright © 2013 John Wiley & Sons, Ltd.)

Based on nationwide data from the French national cancer institute (INCa), we analyzed the evolution of cancer genetics consultations and testing over time, and the uptake of targeted tests in relatives of families with BRCA1/2 or MMR genes mutation. Genetic testing and consultations for familial high-risk individuals are exclusively funded and monitored by the INCa in France. All nationwide cancer genetics centers reported annually standardized parameters of activity from 2003 to 2011. The analysis included a total of 240,134 consultations and 134,652 genetic tests enabling to identify 32,494 mutation carriers. Referral for hereditary breast and ovarian cancer (HBOC) or colorectal cancer predisposition syndromes represented 59 % (141,639) and 23.2 % (55,698) consultations, respectively. From 2003 to 2011, we found a dramatic and steady increase of tests performed for BRCA1/2 (from 2,095 to 7,393 tests/year, P < 0.0001) but not for MMR genes (from 1,144 to 1,635/year, P = NS). The overall percentage of deleterious mutations identified in the probands tested was 13.8 and 20.9 % in HBOC and Lynch syndromes, respectively. Pooled analysis for BRCA1/2 and Lynch syndrome tests showed an inverse relationship between the percentage of mutation detected and the absolute number of tests performed over the time (overall Cochran-Armitage test for trend: P < 0.001). In families with BRCA1/2 or MMR identified mutations, there was an average number of 2.94 and 3.28 relatives performing targeted tests, respectively. This nationwide study shows a lack of referral and genetic testing in Lynch as compared to HBOC syndromes. Only a third of relatives of a proband with a predisposing mutation performed a targeted test. Enhanced information about benefit of genetic testing should be given to clinicians and patients for Lynch syndrome and relatives of a proband carrying an identified predisposing mutation.

Purpose: Diagnostic screening of the BRCA1/2 genes in breast cancer families is mostly done on genomic DNA. For families with a very strong family history and no mutation identified in the coding sequences or the exon-intron boundaries, BRCA1/2 transcripts' analysis is an efficient approach to uncover gene inversion and pre-mRNA splicing defaults missed by conventional DNA-based protocols., Experimental Design: We analyzed RNA from patients of negative BRCA families by reverse transcriptase PCR and identified an insertion in one family that we characterized by sequencing and by using a minigene splicing assay. More than 2,000 additional BRCA1/2 negative families were subsequently screened for this mutation using a dedicated PCR approach., Results: Nine families were found to harbor a BRCA2 mutant transcript containing a 95-nucleotide cryptic exon between exons 12 and 13. This cryptic exon results from a new mutation located deep into intron 12, c.6937+594T > G, which reinforces the strength of a preexisting 5' splice site, turning it into a perfect consensus sequence. It is systematically included in transcripts produced by the mutant allele in cells from mutation carriers or produced by a mutant splicing reporter minigene. The inclusion of the cryptic exon was prevented when we cotransfected the minigene with antisense oligonucleotides complementary to the 3' or mutated 5' splice sites., Conclusion: This first deep intronic BRCA mutation emphasizes the importance of analyzing RNA to provide comprehensive BRCA1/2 diagnostic tests and opens the possibility of using antisense therapy in the future as an alternative strategy for cancer prevention., (©2012 AACR.)

Objective: To estimate the risk of breast cancer associated with diagnostic radiation in carriers of BRCA1/2 mutations., Design: Retrospective cohort study (GENE-RAD-RISK)., Setting: Three nationwide studies (GENEPSO, EMBRACE, HEBON) in France, United Kingdom, and the Netherlands,, Participants: 1993 female carriers of BRCA1/2 mutations recruited in 2006-09., Main Outcome Measure: Risk of breast cancer estimated with a weighted Cox proportional hazards model with a time dependent individually estimated cumulative breast dose, based on nominal estimates of organ dose and frequency of self reported diagnostic procedures. To correct for potential survival bias, the analysis excluded carriers who were diagnosed more than five years before completion of the study questionnaire., Results: In carriers of BRCA1/2 mutations any exposure to diagnostic radiation before the age of 30 was associated with an increased risk of breast cancer (hazard ratio 1.90, 95% confidence interval 1.20 to 3.00), with a dose-response pattern. The risks by quarter of estimated cumulative dose <0.0020 Gy, ≥ 0.0020-0.0065 Gy, ≥ 0.0066-0.0173 Gy, and ≥ 0.0174 Gy were 1.63 (0.96 to 2.77), 1.78 (0.88 to 3.58), 1.75 (0.72 to 4.25), and 3.84 (1.67 to 8.79), respectively. Analyses on the different types of diagnostic procedures showed a pattern of increasing risk with increasing number of radiographs before age 20 and before age 30 compared with no exposure. A history of mammography before age 30 was also associated with an increased risk of breast cancer (hazard ratio 1.43, 0.85 to 2.40). Sensitivity analysis showed that this finding was not caused by confounding by indication of family history., Conclusion: In this large European study among carriers of BRCA1/2 mutations, exposure to diagnostic radiation before age 30 was associated with an increased risk of breast cancer at dose levels considerably lower than those at which increases have been found in other cohorts exposed to radiation. The results of this study support the use of non-ionising radiation imaging techniques (such as magnetic resonance imaging) as the main tool for surveillance in young women with BRCA1/2 mutations.

The aim of this study was to examine the patterns of disclosure of BRCA1/2 genetic test results to employers by unaffected carriers. In a national prospective cohort study on unaffected BRCA1/2 mutation carriers, disclosure to employers was assessed prospectively, using self-administered questionnaires, up to 2 years after their test results were delivered by cancer geneticists. Kaplan-Meier curves and Cox-regression analysis were used to assess the factors associated with time to disclosure to the employer. Mean age of the 146 women BRCA1/2 carriers who were employed when their test results were delivered was 37.1 years (range: 19-57). At the end of the second year of follow-up, 47 of them (32.2%) had disclosed their results to their employers; median time to disclosure was 6 months. Reasons spontaneously expressed were first to inform the employer that medical surveillance/surgery was necessary for cancer risk management although these carriers did not actually have cancer. After multivariate adjustment on age, women with a lower educational level (HRadj=2.00, P=0.026) and those who had undergone prophylactic surgery during the 2 years of follow-up (HRadj=2.18, P=0.019) had disclosed their BRCA status to their employers earlier and more frequently. One-third of the female carriers not affected by breast/ovarian cancer disclosed their BRCA1/2 genetic test results spontaneously to their employers, mainly to inform them that they were disease-free but required medical surveillance or a surgical intervention to reduce the risk of cancer.

Introduction: Mutations in BRCA1 and BRCA2 confer a high risk of breast cancer (BC), but the magnitude of this risk seems to vary according to the study and various factors. Although controversial, there are data to support the hypothesis of allelic risk heterogeneity., Methods: We assessed variation in BC risk according to factors related to pregnancies by location of mutation in the homogeneous risk region of BRCA1 and BRCA2 in 990 women in the French study GENEPSO by using a weighted Cox regression model., Results: Our results confirm the existence of the protective effect of an increasing number of full-term pregnancies (FTPs) toward BC among BRCA1 and BRCA2 mutation carriers (≥3 versus 0 FTPs: hazard ratio (HR) = 0.51, 95% confidence interval (CI) = 0.33 to 0.81). Additionally, the HR shows an association between incomplete pregnancies and a higher BC risk, which reached 2.39 (95% CI = 1.28 to 4.45) among women who had at least three incomplete pregnancies when compared with women with zero incomplete pregnancies. This increased risk appeared to be restricted to incomplete pregnancies occurring before the first FTP (HR = 1.77, 95% CI = 1.19 to 2.63). We defined the TMAP score (defined as the Time of Breast Mitotic Activity during Pregnancies) to take into account simultaneously the opposite effect of full-term and interrupted pregnancies. Compared with women with a TMAP score of less than 0.35, an increasing TMAP score was associated with a statistically significant increase in the risk of BC (P trend = 0.02) which reached 1.97 (95% CI = 1.19 to 3.29) for a TMAP score >0.5 (versus TMAP ≤0.35). All these results appeared to be similar in BRCA1 and BRCA2. Nevertheless, our results suggest a variation in BC risk associated with parity according to the location of the mutation in BRCA1. Indeed, parity seems to be associated with a significantly decreased risk of BC only among women with a mutation in the central region of BRCA1 (low-risk region) (≥1 versus 0 FTP: HR = 0.27, 95% CI = 0.13 to 0.55) (Pinteraction <10-3)., Conclusions: Our findings show that, taking into account environmental and lifestyle modifiers, mutation position might be important for the clinical management of BRCA1 and BRCA2 mutation carriers and could also be helpful in understanding how BRCA1 and BRCA2 genes are involved in BC.

Germline mutations in BRCA1/2 confer a high risk of breast cancer (BC), but the magnitude of this risk varies according to various factors. Although controversial, there are data to support the hypothesis of allelic-risk heterogeneity. We assessed variation in BC risk according to the location of mutations recorded in the French study GENEPSO. Since the women in this study were selected from high-risk families, oversampling of affected women was eliminated by using a weighted Cox-regression model. Women were censored at the date of diagnosis when affected by any cancer, or the date of interview when unaffected. A total of 990 women were selected for the analysis: 379 were classified as affected, 611 as unaffected. For BRCA1, there was some evidence of a central region where the risk of BC is lower (codons 374-1161) (HR = 0.59, P = 0.04). For BRCA2, there was a strong evidence for a region at decreased risk (codons 957-1827) (HR = 0.35, P = 0.005) and for one at increased risk (codons 2546-2968) (HR = 3.56, P = 0.01). Moreover, we found an important association between radiation exposure from chest X-rays and BC risk (HR = 4.29, P < 10(-3)) and a positive association between smoking more than 21 pack-years and BC risk (HR = 2.09, P = 0.04). No significant variation in BC risk associated with chest X-ray exposure, smoking, and alcohol consumption was found according to the location of the mutation in BRCA1 and BRCA2. Our findings are consistent with those suggesting that the risk of BC is lower in the central regions of BRCA1/2. A new high-risk region in BRCA2 is described. Taking into account environmental and lifestyle modifiers, the location of mutations might be important in the clinical management of BRCA mutation carriers.

We described and compared breast and ovarian screening practices in the 2-year period following test result disclosure in female non-carriers from BRCA1/2 mutation-positive families living in two countries, France and Quebec, Canada, which provide universal health care. Four hundred and two (France n=293; Quebec n=109) unaffected female non-carriers from BRCA-proven mutation families provided information about the uptake of mammography, clinical breast examination, breast self-examination, and ovarian ultrasounds using self-administered questionnaires. The frequency of screening practices between study cohorts were compared using logistic regression. Annual mammography was conducted in 23 and 43% of French and Quebecer women participants <50 years of age, respectively (adjusted odds ratio (aOR)=2.72; 95% confidence interval (CI), 1.08-6.81). In women ≥ 50 years of age, mammography was conducted in 49 and 65% of French and Quebecer participants (aOR=1.77; 95% CI, 0.07-4.51). Overall, 33% of French women and 39% of Quebecer women underwent at least one ovarian ultrasound during the 2-year period following BRCA1/2 test result with no significant difference between cohorts of women < 50 years of age. Among older women, Quebecers reported more frequently than French women that they had undergone ultrasound once (aOR=3.00; 95% CI, 1.02-8.83). The frequency of cancer screening practices for female non-carriers from BRCA1/2 mutation-positive families in both France and Quebec exceeded those recommended for similarly aged women in the general population. Our findings highlight the need for clearcut recommendations on the follow-up of women from BRCA1/2 families who are not themselves carriers of a BRCA1/2 mutation.

Purpose: To investigate the medical and psychosocial factors determining the time to prophylactic surgery of unaffected women carriers of a deleterious BRCA1/2 mutation., Methods: Prospective study on a French national cohort of unaffected BRCA1/2 carriers (N = 244); multivariate Cox proportional hazard modeling., Results: Median follow-up time was 2.33 years (range, 0.04-6.84 years). Time to surgery was shorter when the psychological impact of BRCA1/2 result disclosure was stated to be higher (P ≤ 0.01). Those who intended to opt for prophylactic surgery before being tested did so faster and more frequently after test disclosure than those who were undecided/opposed. The older the women were, the faster their uptake of risk-reducing salpingo-oophorectomy (adjusted hazard ratio >2.95; P < 0.001) was; the uptake of those with at least two children was also faster (adjusted hazard ratio = 2.51; [1.38-4.55]). Those who opted most quickly for risk-reducing mastectomy more frequently had a younger child at the time of testing (adjusted hazard ratio = 4.63 [1.56-13.74]). Time to surgery was shorter when there was a first-degree relative with ovarian/breast cancer (P ≤ 0.01)., Conclusion: Time to prophylactic surgery depends on the stated psychological impact of disclosure and on women's cognitive anticipation of surgery after adjusting on sociodemographic characteristics.

PURPOSE Earlier studies have shown that endogenous gonadal hormones play an important role in the etiology of breast cancer among BRCA1/2 mutation carriers. So far, little is known about the safety of exogenous hormonal use in mutation carriers. In this study, we examined the association between oral contraceptive use and risk of breast cancer among BRCA1/2 carriers. PATIENTS AND METHODS In the International BRCA1/2 Carrier Cohort study (IBCCS), a retrospective cohort of 1,593 BRCA1/2 mutation carriers was analyzed with a weighted Cox regression analysis. Results We found an increased risk of breast cancer for BRCA1/2 mutation carriers who ever used oral contraceptives (adjusted hazard ratio [HR] = 1.47; 95% CI, 1.16 to 1.87). HRs did not vary according to time since stopping use, age at start, or calendar year at start. However, a longer duration of use, especially before first full-term pregnancy, was associated with an increased risk of breast cancer for both BRCA1 and BRCA2 mutation carriers (4 or more years of use before first full-term pregnancy: HR = 1.49 [95% CI, 1.05 to 2.11] for BRCA1 carriers and HR = 2.58 [95% CI, 1.21 to 5.49] for BRCA2 carriers). CONCLUSION No evidence was found among BRCA1/2 mutation carriers that current use of oral contraceptives is associated with risk of breast cancer more strongly than is past use, as is found in the general population. However, duration of use, especially before first full-term pregnancy, may be associated with an increasing risk of breast cancer among both BRCA1 and BRCA2 mutation carriers.

Purpose: The debate concerning poorer survival for patients with breast cancer (BC) carrying a BRCA1 germline mutation is unresolved, and requires additional data from population-based studies., Patients and Methods: We followed 232 women with invasive BC under age 46, ascertained prospectively through a French population-based BC registry and tested for BRCA1/2 mutations (median follow-up: 82 months). We compared tumour characteristics and survival rates between 21 BRCA1/2 deleterious mutation carriers and 211 non-carriers., Results: As compared to sporadic tumours, BRCA1/2 tumours showed higher grade (P = 0.02), fewer ductal carcinoma in situ (P = 0.02), more frequent medullary histology (P = 0.02), more frequent negative oestrogen and progesterone receptors (P = 0.001 each). At 5 years, BC-specific survival, metastasis-free survival, ipsilateral recurrence-free survival and contralateral BC-free survival rates for BRCA1/2 mutation carriers were 95.0%, 94.7%, 100% and 90.0% respectively, compared with 89.6%, 78.2%, 88.8% and 94.4% respectively, for non-carriers (not significant). Rates for women carrying only a BRCA1 mutation were 93.3%, 93.3%, 100%, 86.7%, respectively. 76% of BRCA1/2 carriers received chemotherapy., Conclusion: Despite unfavourable tumour features, we found no evidence for poorer short-term survival in BRCA1 mutation carriers compared to non-carriers in this prospective population-based cohort. The high rate of BRCA1 carriers who received chemotherapy for their BC should question the positive impact of this treatment, as suggested by preclinical studies showing increased chemosensitivity of BRCA1-associated tumours.

Marked variation in phenotypic expression among BRCA1 and BRCA2 mutation carriers may be partly explained by modifier genes that influence mutation penetrance. Variation in CAG/CAA repeat lengths coding for stretches of glutamines in the C-terminus of the AIB1 protein (amplified in breast cancer 1, a steroid receptor coactivator) has been proposed to modify the breast cancer risk in women carrying germline BRCA1 mutations. We genotyped the AIB1 repeat length polymorphism from the genomic DNA of a group of 851 BRCA1 and 324 BRCA2 female germline mutation carriers to estimate an association with breast cancer risk modification. Hazard ratios (HR) were calculated using a Cox proportional hazards model. For BRCA1 and BRCA2 mutation carriers, analyzed separately and together, we found that women who carried alleles with 28 or more polyglutamine repeats had no increased risk of breast cancer compared to those who carried alleles with fewer repeats (HR for BRCA1/2 carriers = 0.88, 95% CI [confidence interval] = 0.75-1.04). Analyzing average repeat lengths as a continuous variable showed no excess risk of breast cancer (BC) in BRCA1 or BRCA2 mutation carriers (HR for average repeat length in BRCA1/2 carriers = 1.01, 95% CI = 0.92-1.11). These results strongly suggest that contrary to previous studies, there is no significant effect of AIB1 genetic variation on BC risk in BRCA1 mutation carriers and provide an indication that there is also no strong risk modification in BRCA2 carriers.

The prevalence of BRCA1/2 germ-line mutations was assessed in a prospective population-based series of early-onset breast cancer (BC) patients in France, and the usefulness of a clinical assessment of hereditary BC risk, based on multiple criteria including pedigree structure, was evaluated. Through the Rhone region BC registry, 232 women diagnosed with BC before 46 years of age were included. They were tested for BRCA1/2 mutations an average of 10 months after diagnosis. All the women were classified according to their family history of cancer: high risk of hereditary breast cancer (HBC), low risk of HBC, isolated BC, and unknown HBC risk. Deleterious mutations were observed in 21 women (9.1%): 15 (6.5%) BRCA1 and 6 (2.6%) BRCA2. Mutations were more prevalent in women who developed BC before age 41 than in women who developed BC between ages 41 and 45 (12.8% versus 5.2%, respectively, P = 0.04). A high prevalence of BRCA1/2 mutations was found among women in the high-risk category with particular family features (i.e., small family size, predominantly male pedigree, specific cancers; 23.5%) and among women with isolated BC before age 41 and with five or fewer close adult female relatives (16.6%). According to the 10% probability level recommended by the American Society of Clinical Oncology guidelines for genetic testing of cancer, BRCA1/2 mutation screening should be considered for all women diagnosed before age 41, except for those with isolated BC in a large pedigree including multiple unaffected female relatives. The clinical assessment of HBC risk that we have developed should help in the decision to perform genetic testing., (Copyright 2005 Wiley-Liss, Inc.)

The HH genotype of the nonconservative amino acid substitution polymorphism N372H in the BRCA2 gene was reported to be associated with a 1.3- to 1.5-fold increase in risk of both breast and ovarian cancer. As these studies concerned sporadic cancer cases, we investigated whether N372H and another common variant located in the 5'-untranslated region (203G > A) of the BRCA2 gene modify breast or ovarian cancer risk in BRCA1 mutation carriers. The study includes 778 women carrying a BRCA1 germ-line mutation belonging to 403 families. The two BRCA2 variants were analyzed by the TaqMan allelic discrimination technique. Genotypes were analyzed by disease-free survival analysis using a Cox proportional hazards model. We found no evidence of a significant modification of breast cancer penetrance in BRCA1 mutation carriers by either polymorphism. In respect of ovarian cancer risk, we also saw no effect with the N372H variant but we did observe a borderline association with the 5'-untranslated region 203A allele (hazard ratio, 1.43; CI, 1.01-2.00). In contrast to the result of Healey et al. on newborn females and adult female controls, we found no departure from Hardy-Weinberg equilibrium in the distribution of N372H alleles for our female BRCA1 carriers. We conclude that if these single-nucleotide polymorphisms do modify the risk of cancer in BRCA1 mutation carriers, their effects are not significantly larger than that of N372H previously observed in the general population.