The clinical management of BRCA1 and BRCA2 mutation carriers requires accurate, prospective cancer risk estimates.
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.
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.
BRCA1/2 mutations, family cancer history, and mutation location.
Annual incidences, standardized incidence ratios, and cumulative risks of breast, ovarian, and contralateral breast cancer.
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).
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.
Several reproductive and hormonal factors are known to be associated with ovarian cancer risk in the general population, including parity and oral contraceptive (OC) use. However, their effect on ...ovarian cancer risk for BRCA1 and BRCA2 mutation carriers has only been investigated in a small number of studies.
We used data on 2,281 BRCA1 carriers and 1,038 BRCA2 carriers from the International BRCA1/2 Carrier Cohort Study to evaluate the effect of reproductive and hormonal factors on ovarian cancer risk for mutation carriers. Data were analyzed within a weighted Cox proportional hazards framework.
There were no significant differences in the risk of ovarian cancer between parous and nulliparous carriers. For parous BRCA1 mutation carriers, the risk of ovarian cancer was reduced with each additional full-term pregnancy (P trend = 0.002). BRCA1 carriers who had ever used OC were at a significantly reduced risk of developing ovarian cancer (hazard ratio, 0.52; 95% confidence intervals, 0.37-0.73; P = 0.0002) and increasing duration of OC use was associated with a reduced ovarian cancer risk (P trend = 0.0004). The protective effect of OC use for BRCA1 mutation carriers seemed to be greater among more recent users. Tubal ligation was associated with a reduced risk of ovarian cancer for BRCA1 carriers (hazard ratio, 0.42; 95% confidence intervals, 0.22-0.80; P = 0.008). The number of ovarian cancer cases in BRCA2 mutation carriers was too small to draw definitive conclusions.
The results provide further confirmation that OC use, number of full-term pregnancies, and tubal ligation are associated with ovarian cancer risk in BRCA1 carriers to a similar relative extent as in the general population.
Le cancer du sein est, en France, le plus fréquent des cancers chez la femme et la première cause de décès par cancer. L’identification des femmes, dont le niveau de risque de cancer du sein est ...« élevé » ou « très élevé » selon la terminologie de la Haute Autorité de Santé en 2014, est essentielle puisque leur prise en charge, en termes de dépistage et de prévention, pourra ainsi être adaptée.
Les femmes prédisposées génétiquement sont à risque très élevé de cancer du sein. La consultation d’oncogénétique a pour but d’étudier l’histoire personnelle et familiale de cancers de la patiente afin d’identifier les situations évocatrices d’une prédisposition héréditaire aux cancers du sein et/ou des ovaires et leur proposer des analyses de biologie moléculaire. Une liste de 13 gènes devant être étudiés face à ce risque héréditaire a été établie en France en 2017 (Groupe Génétique et Cancer – Unicancer).
La mise en évidence d’une mutation constitutionnelle délétère des gènes BRCA1, BRCA2, PALB2, TP53, CDH1, PTEN confère un niveau de risque de cancer du sein considéré comme « très élevé » chez les femmes porteuses. Elles se voient recommander une surveillance mammaire similaire aux femmes porteuses d’une mutation d’un des deux gènes BRCA1/BRCA2 (Référentiel INCa 2017).
Une mutation délétère sur un gène d’intérêt est identifiée dans environ 10 % des familles testées. Lorsque l’analyse est négative, l’évaluation faite par l’onco-généticien permet de distinguer les familles où les femmes restent à un risque « élevé » de cancer du sein (Référentiel HAS 2014 pour le dépistage) de celles où les femmes sont à un risque « très élevé » (Référentiel INCa 2017 pour le dépistage et la prévention).
In France, breast cancer is the most common cancer among women and the leading cause of cancer deaths. Identifying women with a “high” or “very high” breast cancer risk, according the terminology of the Haute Autorité de Santé 2014 guidelines, is essential to offer them special cares in term of screening and prevention.
Women genetically predisposed have a very high risk of breast cancer. During the oncogenetic specialist consultation, familial and personal history of cancer is taken into account to evaluate the risk of hereditary Breast/Ovarian syndrome and thus the need of a genetic screening. In 2017, a list of 13 genes involved in hereditary ovarian or breast cancer has been established in France (Genetic and Cancer Group – Unicancer).
Women carrying a BRCA1, BRCA2, PALB2, TP53, CDH1, PTEN mutation have a higher risk of breast cancer and are considered as “high risk”. Therefore, medical breast surveillance similar to carriers of BRCA1/BRCA2 mutation is recommended for these patients (INCa guidelines 2017).
However a mutation in one of those genes is only identified in approximatively 10 % of the screened families. The oncogenetic specialist's assessment distinguishes families in which women remain at a “high” risk of breast cancer (HAS 2014 for screening) from those where women have a “very high” risk (INCa guidelines 2017 for screening and prevention).
Women who carry germline mutations in the BRCA1 and BRCA2 genes are at greatly increased risk of breast cancer (BC). Numerous studies have shown that moderate to high doses of ionizing radiation are ...a risk factor for BC. Because of the role of the BRCA proteins in DNA repair, we hypothesized that BRCA carriers might be more sensitive to ionizing radiation than women in the general population.
A retrospective cohort study of 1,601 female BRCA1/2 carriers was performed. Risk of breast cancer from exposure to chest x-rays, as assessed by questionnaire data, was analyzed using a weighted Cox proportional hazards model.
In this cohort, any reported exposure to chest x-rays was associated with an increased risk of BC (hazard ratio HR = 1.54; P = .007). This risk was increased in carrier women aged 40 years and younger (HR = 1.97; P < .001) and in women born after 1949 (HR = 2.56; P < .001), particularly those exposed only before the age of 20 years (HR = 4.64; P < .001).
In our series of BRCA carriers, we detected a relatively large effect on BC risk with a level of radiation exposure that is at least an order of magnitude lower than in previously studied medical radiation-exposed cohorts. Although part of this increase may be attributable to recall bias, the observed patterns of risk in terms of age at exposure and attained age are consistent with those found in previous studies. If confirmed, the results have important implications for the use of x-ray imaging in young BRCA1/2 carriers.
Genetic tests in families with a mutation related to breast and ovarian cancers (BRCA1/2) are now offered to the persons before completion of their reproductive project. The aim of this qualitative ...study was to descriptively explore how the issues of reproduction are faced in women belonging to these families, and how the possible use of prenatal diagnostic (PND) and preimplantation genetic diagnosis (PGD) would be faced in a theoretical context. We conducted in-depth interviews, face to face, according to the so-called Grounded Theory approach. Twenty women with a BRCA genetic mutation participated in the study (age range: 31-57 years); 12 have had a breast and/or ovarian cancer. The knowledge of having the mutation did not modify the parental project; however prophylactic anexectomy was likely to alter it in some women. If the majority of women were in favor of PGD (n = 14), medical termination of pregnancy was a constraint towards the position in relation to PND. Besides ethical and moral arguments, the women's attitudes were constructed differently according to their own personal or familial experience of the disease. The women's perceptions of the cancer severity, risk and cure were organized according to this experience.
Providing accurate estimates of cancer risks is a major challenge in the clinical management of Lynch syndrome.
To estimate the age-specific cumulative risks of developing various tumors using a ...large series of families with mutations of the MLH1, MSH2, and MSH6 genes.
Families with Lynch syndrome enrolled between January 1, 2006, and December 31, 2009, from 40 French cancer genetics clinics participating in the ERISCAM (Estimation des Risques de Cancer chez les porteurs de mutation des gènes MMR) study; 537 families with segregating mutated genes (248 with MLH1; 256 with MSH2; and 33 with MSH6) were analyzed.
Age-specific cumulative cancer risks estimated using the genotype restricted likelihood (GRL) method accounting for ascertainment bias.
Significant differences in estimated cumulative cancer risk were found between the 3 mutated genes (P = .01). The estimated cumulative risks of colorectal cancer by age 70 years were 41% (95% confidence intervals CI, 25%-70%) for MLH1 mutation carriers, 48% (95% CI, 30%-77%) for MSH2, and 12% (95% CI, 8%-22%) for MSH6. For endometrial cancer, corresponding risks were 54% (95% CI, 20%-80%), 21% (95% CI, 8%-77%), and 16% (95% CI, 8%-32%). For ovarian cancer, they were 20% (95% CI, 1%-65%), 24% (95% CI, 3%-52%), and 1% (95% CI, 0%-3%). The estimated cumulative risks by age 40 years did not exceed 2% (95% CI, 0%-7%) for endometrial cancer nor 1% (95% CI, 0%-3%) for ovarian cancer, irrespective of the gene. The estimated lifetime risks for other tumor types did not exceed 3% with any of the gene mutations.
MSH6 mutations are associated with markedly lower cancer risks than MLH1 or MSH2 mutations. Lifetime ovarian and endometrial cancer risks associated with MLH1 or MSH2 mutations were high but do not increase appreciably until after the age of 40 years.
In case of suspected hereditary predisposition to digestive cancers, next-generation sequencing can analyze simultaneously several genes associated with an increased risk of developing these tumors. ...Thus, "Gastro Intestinal" (GI) gene panels are commonly used in French molecular genetic laboratories. Lack of international recommendations led to disparities in the composition of these panels and in the management of patients.
To harmonize practices, the Genetics and Cancer Group (GGC)-Unicancer set up a working group who carried out a review of the literature for 31 genes of interest in this context and established a list of genes for which the estimated risks associated with pathogenic variant seemed sufficiently reliable and high for clinical use. Pancreatic cancer susceptibility genes have been excluded.
This expertise defined a panel of 14 genes of confirmed clinical interest and relevant for genetic counseling: APC, BMPR1A, CDH1, EPCAM, MLH1, MSH2, MSH6, MUTYH, PMS2, POLD1, POLE, PTEN, SMAD4 and STK11. The reasons for the exclusion of the others 23 genes have been discussed. The paucity of estimates of the associated tumor risks led to the exclusion of genes, in particular CTNNA1, MSH3 and NTHL1, despite their implication in the molecular pathways involved in the pathophysiology of GI cancers.
A regular update of the literature is planned to up-grade this panel of genes in case of new data on candidate genes. Genetic and epidemiological studies and international collaborations are needed to better estimate the risks associated with the pathogenic variants of these genes either selected or not in the current panel.
A large well-annotated recent international cohort of Li-Fraumeni (LFS) patients with early-stage breast cancer (BC) was examined for shared features.
This multicentre cohort study included females ...with a germline TP53 pathogenic or likely pathogenic variant and nonmetastatic BC diagnosed between 2002-2022. Clinical and genetic data were obtained from institutional registries and clinical charts. Descriptive statistics were utilized to summarize proportions and differences were assessed by Chi square or Wilcoxon rank sum tests. Metachronous contralateral breast cancer (CBC) risk, radiation-induced sarcoma risk, and recurrence-free survival (RFS) were analyzed by Kaplan-Meier methodology.
Among 227 females who met study criteria, the median age of first BC diagnosis was 37 years (range 21-71), 11.9% presented with bilateral synchronous BC and 18.1% had ductal carcinoma in situ (DCIS) only. In total, 166 (73.1%) underwent mastectomies including 67 bilateral mastectomies as first BC surgery. Among those with retained breast tissue, CBC rate was 25.3% at 5-years. Among 186 invasive tumors, 72.1% were stages I-II, 48.9% node-negative, and the most common subtypes were HR+/HER2- (40.9%) and HR+/HER2 + (34.4%). At a median follow-up of 69.9 months (IQR 32.6-125.9), invasive HR+/HER2- disease had the highest recurrence risk among the subtypes (5-year RFS 61.1%, p = .0012). Among those who received radiation therapy (n = 79), the 5-year radiation-induced sarcoma rate was 4.8%.
We observed high rates of DCIS, HR+ and HER2+ breast cancers, with a worse outcome in the HR+/HER2- luminal tumors despite appropriate treatment. Confirmation of these findings in further studies could have implications for BC care in LFS.
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.
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.
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.
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