Mosaic BRCA1 promoter methylation contribution in hereditary breast/ovarian cancer pedigrees.

PURPOSE: Mosaic BRCA1 promoter methylation (BRCA1meth) increases the risk of early-onset breast cancer, triple-negative breast cancer and ovarian cancer. As mosaic BRCA1meth are believed to occur de novo, their role in family breast/ovarian cancer has not been assessed. PATIENTS: Blood-derived DNA from 20 unrelated affected cases from families with aggregation of breast/ovarian cancer, but with no germline pathogenic variants in BRCA1/2, PALB2 or RAD51C/D, were screened by methylation-sensitive high-resolution melting. CpG analysis was performed by pyrosequencing on blood and buccal swab. Two probands carried a pathogenic variant in a moderate-penetrance gene (ATM and BARD1), and 8 of 18 others (44%) carried BRCA1meth (vs none of the 20 age-matched controls). Involvement of BRCA1 in tumourigenesis in methylated probands was demonstrated in most tested cases by detection of a loss of heterozygosity and a homologous recombination deficiency signature. Among the eight methylated probands, two had relatives with breast cancer with detectable BRCA1meth in blood, including one with high methylation levels in two non-tumour tissues. CONCLUSIONS: The high prevalence of mosaic BRCA1meth in patients with breast/ovarian cancer with affected relatives, as well as this first description of a family aggregation of mosaic BRCA1meth, shows how this de novo event can contribute to hereditary breast/ovarian cancer pedigrees.

APC germline pathogenic variants and epithelial ovarian cancer: causal or coincidental findings?

APC germline pathogenic variants result in predisposition to familial adenomatous polyposis and extraintestinal tumours such as desmoid fibromatosis, medulloblastomas and thyroid cancers. They have also been recently involved in ovarian microcystic stromal tumours. APC inactivation has been described at the tumour level in epithelial ovarian cancers (EOCs). Here, we report the identification of APC germline pathogenic variants in two patients diagnosed with premenopausal EOC in early 30s, with no other pathogenic variant detected in the known ovarian cancer predisposing genes. Subsequent tumour analysis showed neither a second hit of APC inactivation nor ß-catenin activation. Both tumours did not have a homologous recombination (HR) deficiency, pointing towards the implication of other genes than those involved in HR. APC may contribute to the carcinogenesis of EOC in a multifactorial context. Further studies are required to clarify the role of APC in predisposition to EOC.

Associations of height, body mass index, and weight gain with breast cancer risk in carriers of a pathogenic variant in BRCA1 or BRCA2: the BRCA1 and BRCA2 Cohort Consortium.

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/m2, 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/m2, 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.

Hereditary cancer predispositions: Comparison of multigene panel sequencing on fresh-frozen breast/ovarian tumor versus blood.

In breast or ovarian cancer (BC/OC) patients with evocative personal and/or family history, multigene panel sequencing is performed on blood to diagnose hereditary predispositions. Additionally, BRCA1/BRCA2 testing can be performed on tumor sample for therapeutic purpose. The accuracy of multigene panel tumor analysis on BC/OC to detect predisposing germline pathogenic variants (gPV) has not been precisely assessed. By comparing sequencing data from blood and fresh-frozen tumor we show that tumor genomic instability causes pitfalls to consider when performing tumor testing to detect gPV. Even if loss of heterozygosity increases germline signal in most cases, somatic copy number variants (CNV) can mask germline CNV and collapse point gPV variant allele frequency (VAF). Moreover, VAF does not allow an accurate distinction between germline and somatic pathogenic variants.

Enhancing the BOADICEA cancer risk prediction model to incorporate new data on RAD51C, RAD51D, BARD1 updates to tumour pathology and cancer incidence.

BACKGROUND: BOADICEA (Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm) for breast cancer and the epithelial tubo-ovarian cancer (EOC) models included in the CanRisk tool (www.canrisk.org) provide future cancer risks based on pathogenic variants in cancer-susceptibility genes, polygenic risk scores, breast density, questionnaire-based risk factors and family history. Here, we extend the models to include the effects of pathogenic variants in recently established breast cancer and EOC susceptibility genes, up-to-date age-specific pathology distributions and continuous risk factors. METHODS: BOADICEA was extended to further incorporate the associations of pathogenic variants in BARD1, RAD51C and RAD51D with breast cancer risk. The EOC model was extended to include the association of PALB2 pathogenic variants with EOC risk. Age-specific distributions of oestrogen-receptor-negative and triple-negative breast cancer status for pathogenic variant carriers in these genes and CHEK2 and ATM were also incorporated. A novel method to include continuous risk factors was developed, exemplified by including adult height as continuous. RESULTS: BARD1, RAD51C and RAD51D explain 0.31% of the breast cancer polygenic variance. When incorporated into the multifactorial model, 34%-44% of these carriers would be reclassified to the near-population and 15%-22% to the high-risk categories based on the UK National Institute for Health and Care Excellence guidelines. Under the EOC multifactorial model, 62%, 35% and 3% of PALB2 carriers have lifetime EOC risks of <5%, 5%-10% and >10%, respectively. Including height as continuous, increased the breast cancer relative risk variance from 0.002 to 0.010. CONCLUSIONS: These extensions will allow for better personalised risks for BARD1, RAD51C, RAD51D and PALB2 pathogenic variant carriers and more informed choices on screening, prevention, risk factor modification or other risk-reducing options.

Co-occurrence of germline BRCA1 and CDH1 pathogenic variants.

INTRODUCTION: We report a very rare case of familial breast cancer and diffuse gastric cancer, with germline pathogenic variants in both BRCA1 and CDH1 genes. To the best of our knowledge, this is the first report of such an association.Family description: The proband is a woman diagnosed with breast cancer at the age of 52 years. She requested genetic counselling in 2012, at the age of 91 years, because of a history of breast cancer in her daughter, her sister, her niece and her paternal grandmother and was therefore concerned about her relatives. Her sister and maternal aunt also had gastric cancer. She was tested for several genes associated with hereditary breast cancer. RESULTS: A large deletion of BRCA1 from exons 1 to 7 and two CDH1 pathogenic cis variants were identified. CONCLUSION: This complex situation is challenging for genetic counselling and management of at-risk individuals.

Predictive factors of 5-year relapse-free survival in HR+/HER2- breast cancer patients treated with neoadjuvant endocrine therapy: pooled analysis of two phase 2 trials.

BACKGROUND: Few data are available on survival and predictive factors in early breast cancer (BC) patients treated with neoadjuvant endocrine therapy (NET). METHODS: This is a pooled analysis of two multicentre, randomised non-comparative phase 2 clinical trials evaluating neoadjuvant anastrozole and fulvestrant efficacy for postmenopausal HR+/HER2- breast cancer patients: HORGEN (NCT00871858) and CARMINA02 (NCT00629616) studies. RESULTS: In total, 236 patients were included in CARMINA02 and HORGEN trials. Modified intention-to-treat analysis was available for 217 patients. Median follow-up was 65.2 months. Relapse-free survival (RFS) and overall survival (OS) at 5 years were 83.7% (95% CI: 77.9-88) and 92.7% (95% CI: 88.2-95.6), respectively, with no difference between treatment arms. On univariate analysis, tumour staging (T2 vs T3-4; p = 0.0001), Ki-67 at surgery (≤10% vs >10%; p = 0.0093), pathological tumour size (pT1-2 vs pT3-4; p = 0.0012) and node status (pN negative vs positive; p = 0.007), adjuvant chemotherapy (p = 0.0167) and PEPI score (PEPI group I + II vs III; p = 0.0004) were associated with RFS. No events were observed in patients with pathological response according to the Sataloff classification. Multivariate analysis showed that preoperative endocrine prognostic index (PEPI) group III was associated with significantly worse RFS (p = 0.0069, hazard ratio = 3.33 (95% CI: 1.39-7.98)). CONCLUSIONS: Postmenopausal HR+/HER2- breast cancer patients receiving NET generally have a favourable outcome. The PEPI score identifies a subset of patients of poorer prognosis who are candidates for further additional treatment.

Parental disclosure of positive BRCA1/2 mutation status to children 10 years after genetic testing.

The disclosure of genetic information is an important issue in cancer prevention. This study based on a French national cohort of BRCA1/2 mutation carriers (GENEPSO-PS cohort, N=233) aimed to assess the prevalence of parental disclosure of genetic information to children 10 years after genetic testing, with a focus on gender differences. Most participants (n = 193, 131 women) reported having children. A total of 72.0% of offspring had received genetic information (88.8% for adult offspring, p < .001), with no differences according to the gender of the mutation-carrying parent. While female carriers disclosed genetic information more often than male carriers (54.1% versus 38.3%, p = .029), they did so irrespective of the gender of their offspring. Moreover, female carriers who had developed incident cancer after genetic testing disclosed genetic information more frequently than unaffected female carriers (70.7% versus 48.5%, p = .005). A multivariate analysis confirmed the effects of both gender and cancer on disclosure to offspring. The same results were obtained when the analysis was restricted to adult offspring. This study reveals high rates of disclosure of positive BRCA1/2 mutation status to children 10 years after genetic testing, irrespective of the gender of the carrier/offspring. However, female carriers disclosed genetic information more frequently than male carriers.

Uptake of genetic counseling among adult children of BRCA1/2 mutation carriers in France.

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.

Febrile neutropenia in adjuvant and neoadjuvant chemotherapy for breast cancer: a retrospective study in routine clinical practice from a single institution.

BACKGROUND: Febrile neutropenia (FN) is one of the most common and most critical adverse effects of chemotherapy. Despite many existing guidelines based on the use of granulocyte-colony stimulating factor (G-CSF), FN continues to impair the quality of life and interfere with the treatment of many patients. The purpose of this study was to assess the incidence and management of FN associated with chemotherapy for early breast cancer in routine clinical practice. METHODS: All patients with early-stage breast cancer (ESBC) treated by chemotherapy at Institut Curie, Hôpital René Huguenin, in 2014 were retrospectively included. The incidence and management of FN were reported. Risk factors associated with FN were studied by robust-error-variance Poisson regression. RESULTS: A total of 524 patients received either neoadjuvant (N = 130) or adjuvant chemotherapy (N = 394). Most patients (80%) were treated with a combination of 5-fluorouracil, epirubicin, and cyclophosphamide (FEC100; 3 cycles) followed by docetaxel 100 mg/m2 (D; 3 cycles). The overall incidence of FN was 17%. Eighteen percent of patients received primary prophylaxis (PP) for FN with G-CSF, using pegfilgrastim in 64% of cases and 74% of patients over the age of 70 received PP. Less than 5% of patients who received PP experienced FN. Recurrent FN after secondary prophylaxis was observed in 9% of patients. Forty-seven percent of cases of FN occurred after the first cycle and 30% occurred after the fourth cycle, corresponding to D ± trastuzumab (T). The FEC100 regimen was associated with a relative risk of FN of 1.98 (p = 0.09). Autoimmune (AI) and inflammatory diseases were associated with a higher risk of FN (RR 3.08; p < 0.01). No significant difference in the incidence of FN was observed between adjuvant and neoadjuvant chemotherapy. FN was managed on an outpatient basis in 72% of cases. Outpatients with FN were mainly treated by a combination of amoxicillin-clavulanic acid and ciprofloxacin. Dose reduction or chemotherapy regimen modification were necessary in 25% of patients after FN. No toxic death was reported. CONCLUSION: The incidence of FN induced by adjuvant/neoadjuvant chemotherapy in ESBC is higher in routine clinical practice than in clinical trials. AI or inflammatory diseases were significant independent risk factors for FN. Primary prophylaxis in patients at risk (elderly, comorbid patients), especially treated with the FEC regimen, is the keystone of management of this adverse effect. Prevention and management of FN to ensure the patient's safety and quality of life are a major issue for both medical oncologists and supportive care physicians.

Efficacy of anthracycline/taxane-based neo-adjuvant chemotherapy on triple-negative breast cancer in BRCA1/BRCA2 mutation carriers.

This study aims to estimate the pathologic complete response (pCR) rate after neo-adjuvant chemotherapy and to compare disease-free survival (DFS) and overall survival (OS) between pCR and non-pCR groups of patients with triple-negative breast cancer (TNBC) and deleterious BRCA1 or BRCA2 mutation. We carried out a retrospective analysis of 53 patients including 46 BRCA1, 6 BRCA2, and 1 combined BRCA1 and BRCA2 mutation. All patients had been diagnosed with triple-negative breast cancer (TNBC) between 1997 and 2014. Neo-adjuvant therapy consisted of regimens that were based on anthracycline or an anthracycline-taxane doublet. DFS included any relapse or second cancer. The Kaplan-Meier method and the log-rank test were used to compare pCR and non-pCR groups. A pCR was observed in 23 (42.6% [95% CI, 29.2%-56.8%]) of the TNBC included. The pCR rate was 38.3% [95% CI, 26%-55%] among BRCA1 mutation carriers, and 66% among the 6 BRCA2 mutation carriers. Median follow-up was 4.4 years (range 0.62-16.2 years) and did not differ between the groups (P = .25). Fifteen relapses and six second cancers were recorded during the follow-up period. Eleven deaths occurred, all of which were in the non-pCR group. DFS (P < .01) and OS (P < .01) were significantly better in the pCR group than the non-pCR group. This study shows a high pCR rate after neo-adjuvant therapy in BRCA-mutated triple-negative breast cancer, and the survival results confirm the prognostic value of pCR in this group. These outcomes should be considered as a basis of comparison to be used by future studies about new therapies in this domain.

Randomized phase 2 neoadjuvant trial evaluating anastrozole and fulvestrant efficacy for postmenopausal, estrogen receptor-positive, human epidermal growth factor receptor 2-negative breast cancer patients: Results of the UNICANCER CARMINA 02 French trial (UCBG 0609).

BACKGROUND: Treatment strategies for locally advanced breast cancer in elderly patients too frail to receive neoadjuvant chemotherapy and the introduction of new classes of drugs in the early 2000s have led to the consideration of endocrine therapy as a neoadjuvant treatment for younger hormone receptor (HR)-positive, postmenopausal patients not eligible for primary breast-conserving surgery (BCS). METHODS: This was a multicenter, phase 2, randomized trial designed to evaluate as its primary objective the clinical response rate after up to 6 months of neoadjuvant endocrine therapy (NET) alone in HR-positive/human epidermal growth factor receptor 2 (HER2)-negative patients with 1 mg of anastrozole (arm A) or 500 mg of fulvestrant (arm B). Secondary objectives included the BCS rate, tumor response assessment (breast ultrasound and magnetic resonance imaging), pathological response (Sataloff classification), safety profile, relapse-free survival (RFS), and predictive markers of responses and outcomes. RESULTS: From October 2007 to April 2011, 116 women (mean age, 71.6 years) with operable infiltrating breast adenocarcinoma (T2-T4, N0-N3, M0) were randomized to receive anastrozole or fulvestrant. The clinical response rates at 6 months were 52.6% (95% confidence interval [CI], 41%-64%) in arm A and 36.8% (95% CI, 25%-49%) in arm B. BCS was performed for 57.6% of arm A patients and 50% of arm B patients. The RFS rates at 3 years were 94.9% in arm A and 91.2% in arm B. The Preoperative Endocrine Prognostic Index status was significantly predictive of RFS. Both treatments were well tolerated. CONCLUSIONS: Both drugs are effective and well tolerated as NET in postmenopausal women with HR-positive/HER2-negative breast cancer. NET could be considered a treatment option in this subpopulation. Cancer 2016;122:3032-3040. © 2016 American Cancer Society.

Disclosure of research results: a randomized study on GENEPSO-PS cohort participants.

BACKGROUND: There exist no recommendations as to how aggregate research results should best be disclosed to long-term cohort participants. OBJECTIVE: To study the impact of cohort results disclosure documents of various kinds on participants' satisfaction. DESIGN: Randomized study with a 2x2 factorial design. SETTING AND PARTICIPANTS: The GENEPSO-PS cohort is used to study the psychosocial characteristics and preventive behaviour of both BRCA1/2 carriers and non-carriers; 235 participants wishing to receive 'information about the survey results' answered a self-administered questionnaire. INTERVENTIONS: The impact of providing the following items in addition to a leaflet about aggregate psychosocial research results was investigated (i) an up-to-date medical information sheet about BRCA1/2 genetic topics, (ii) a photograph with the names of the researchers. MAIN OUTCOME MEASURES: Satisfaction profiles drawn up using cluster analysis methods. RESULTS: Providing additional medical and/or research team information had no significant effect on satisfaction. The patients attributed to the 'poorly satisfied' group (n = 60, 25.5%) differed significantly from those in the 'highly satisfied' group (n = 51, 21.7%): they were younger [odds ratio (OR) = 0.96, 95% confidence interval (0.92-0.99), P = 0.028], less often had a daughter [OR = 4.87 (1.80-13.20), P = 0.002], had reached a higher educational level [OR = 2.94 (1.24-6.95), P = 0.014] and more frequently carried a BRCA1/2 mutation [OR = 2.73 (1.20-6.23), P = 0.017]. CONCLUSIONS: This original approach to disclosing research results to cohort participants was welcomed by most of the participants, but less by the more educated and by BRCA1/2 carriers. Although an easily understandable document is necessary, it might also be worth providing some participants with more in-depth information.

Cigarette smoking in women after BRCA1/2 genetic test disclosure: a 5-year follow-up study of the GENEPSO PS cohort.

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.

Which factors predict proposal and uptake of psychological counselling after BRCA1/2 test result disclosure?

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.

CDH1 germline mutations and the hereditary diffuse gastric and lobular breast cancer syndrome: a multicentre study.

INTRODUCTION: CDH1 predisposes primarily to diffuse gastric cancer (DGC). Multiple DGC cases in a family, DGC at a young age in an individual or the combination of DGC andlobular breast cancer (LBC) in an individual or a family define the hereditary DGC syndrome (HDGC), and testing for germline CDH1 mutations is warranted in HDGC. METHODS AND RESULTS: We report all index cases from Ile-de-France in which a germline CDH1 mutation has been identified. Out of 18 cases, 7 do not fulfil the HDGC-defining criteria. Three of them are women who presented initially with bilateral LBC below age 50, without personal or family history of DGC, and who subsequently developed symptomatic DGC. DISCUSSION: Our series of CDH1 mutation carriers is the largest to date and demonstrates that LBC might be the first manifestation of HDGC. A personal or family history of multiple LBCs at a young age, even without DGC, should prompt CDH1 mutation screening. It is paramount to identify mutation carriers early, so that they can benefit from prophylactic gastrectomy before they develop symptomatic, highly lethal DGC. We recommend a revision of the HDGC-defining criteria and propose for consideration the name 'Hereditary Diffuse Gastric and Lobular Breast Cancer' instead of HDGC.

Male breast cancer: No evidence for mosaic BRCA1 promoter methylation involvement.

Breast cancers (BC) are rare in men and are often caused by constitutional predisposing factors. In women, mosaic BRCA1 promoter methylations (MBPM) are frequent events, detected in 4-8% of healthy subjects. This constitutional epimutation increases risk of early-onset and triple-negative BC. However, the role of MBPM in male BC predisposition has never been assessed. We screened 40 blood samples from men affected by BC, and performed extensive tumour analysis on MBPM-positive patients. We detected two patients carrying MBPM. Surprisingly, tumour analysis revealed that neither of these two male BCs were caused by the constitutional BRCA1 epimutations carried by the patients.

miRNA expression profiling of inflammatory breast cancer identifies a 5-miRNA signature predictive of breast tumor aggressiveness.

IBC (inflammatory breast cancer) is a rare but very aggressive form of breast cancer with a particular phenotype. The molecular mechanisms responsible for IBC remain largely unknown. In particular, genetic and epigenetic alterations specific to IBC remain to be identified. MicroRNAs, a class of small noncoding RNAs able to regulate gene expression, are deregulated in breast cancer and may therefore serve as tools for diagnosis and prediction. This study was designed to determine miRNA expression profiling (microRNAome) in IBC. Quantitative RT-PCR was used to determine expression levels of 804 miRNAs in a screening series of 12 IBC compared to 31 non-stage-matched non-IBC and 8 normal breast samples. The differentially expressed miRNAs were then validated in a series of 65 IBC and 95 non-IBC. From a set of 18 miRNAs of interest selected from the screening series, 13 were differentially expressed with statistical significance in the validation series of IBC compared to non-IBC. Among these, a 5-miRNA signature comprising miR-421, miR-486, miR-503, miR-720 and miR-1303 was shown to be predictive for IBC phenotype with an overall accuracy of 89%. Moreover, multivariate analysis showed that this signature was an independent predictor of poor Metastasis-Free Survival in non-IBC patients.

Association and performance of polygenic risk scores for breast cancer among French women presenting or not a familial predisposition to the disease.

BACKGROUND: Three partially overlapping breast cancer polygenic risk scores (PRS) comprising 77, 179 and 313 SNPs have been proposed for European-ancestry women by the Breast Cancer Association Consortium (BCAC) for improving risk prediction in the general population. However, the effect of these SNPs may vary from one country to another and within a country because of other factors. OBJECTIVE: To assess their associated risk and predictive performance in French women from (1) the CECILE population-based case-control study, (2) BRCA1 or BRCA2 (BRCA1/2) pathogenic variant (PV) carriers from the GEMO study, and (3) familial breast cancer cases with no BRCA1/2 PV and unrelated controls from the GENESIS study. RESULTS: All three PRS were associated with breast cancer in all studies, with odds ratios per standard deviation varying from 1.7 to 2.0 in CECILE and GENESIS, and hazard ratios varying from 1.1 to 1.4 in GEMO. The predictive performance of PRS313 in CECILE was similar to that reported in BCAC but lower than that in GENESIS (area under the receiver operating characteristic curve (AUC) = 0.67 and 0.75, respectively). PRS were less performant in BRCA2 and BRCA1 PV carriers (AUC = 0.58 and 0.54 respectively). CONCLUSION: Our results are in line with previous validation studies in the general population and in BRCA1/2 PV carriers. Additionally, we showed that PRS may be of clinical utility for women with a strong family history of breast cancer and no BRCA1/2 PV, and for those carrying a predicted PV in a moderate-risk gene like ATM, CHEK2 or PALB2.