French college of gynecologists and obstetricians (CNGOF) recommendations for clinical practice: Place of breast self-examination in screening strategies.

Breast cancer is the most common female cancer in the world. Numerous studies have shown that the risk of metastatic disease increases with tumor volume. In this context, it is useful to assess whether the regular practice of formal breast self-examination (BSE) as opposed to breast awareness has an impact on the number of cancers diagnosed, their stage, the treatments used and mortality. DESIGN: The Commission of Senology (CS) of the Collège National de Gynécologie et Obstétrique Français (CNGOF) respected and followed the Grading of Recommendations Assessment, Development and Evaluation method to assess the quality of the evidence on which the recommendations were based. METHODS: The CS studied 16 questions individualizing four groups of women (general population, women aged over 75, high-risk women, and women previously treated for breast cancer). For each situation, it was determined whether the practice of BSE versus abstention from this examination led to detection of more breast cancers and/or recurrences and/or reduced treatment and/or increased survival. RESULTS: BSE should not be recommended for women in the general population, who otherwise benefit from clinical breast examination by practitioners from the age of 25, and from organized screening from 50 to 74 (strong recommendation). In the absence of data on the benefits of BSE in patients aged over 75, for those at high risk and those previously treated for breast cancer, the CS was unable to issue recommendations. Thus, if women in these categories wish to undergo BSE, information on the benefits and risks observed in the general population must be given, notably that BSE is associated with a higher number of referrals, biopsies, and a reduced quality of life.

[Place of breast self-examination in screening strategies. French College of Gynecologists and Obstetricians (CNGOF) recommendations for clinical practice]. / Recommandations pour la pratique clinique du CNGOF. Place de l'auto-examen des seins dans les stratégies de dépistage.

OBJECTIVES: Breast cancer is the most common female cancer in the world. In France, over 60,000 new cases are currently diagnosed, and 12,000 deaths are attributed to it annually. Numerous studies have shown that the risk of metastatic disease increases with tumor volume. In this context, it is useful to assess whether the regular practice of breast self-examination (BSE) has an impact on the number of cancers diagnosed, their stage, the treatments used and mortality. DESIGN: the CNGOF's Commission de Sénologie (CS), composed by 17 experts and 3 invited members, drew up these recommendations. No funding was provided for the development of these recommendations. The CS respected and followed the GRADE (Grading of Recommendations Assessment, Development and Evaluation) method to assess the quality of the evidence on which the recommendations were based. METHODS: The CS studied 16 questions concerning BSE, individualizing four groups of women (general population, women aged over 75, high-risk women, and women previously treated for breast cancer). For each situation, it was determined whether the practice of BSE compared with abstention from this examination led to the detection of more breast cancers and/or recurrences and/or reduced treatment and/or increased survival. RESULTS: BSE should not be recommended for women in the general population, who otherwise benefit from a clinical breast examination (by the attending physician or gynecologist) from the age of 25, and from organized screening from 50 to 74 (strong recommendation). However, in the absence of data on the role of BSE in patients aged over 75, those at high risk of breast cancer and those previously treated for breast cancer, the CS was unable to issue recommendations. Thus, if women in these latter categories wish to undergo BSE, they must be given rigorous training in the technique, and information on the benefits and risks observed in the general population. Finally, the CS invites all women who detect a change or abnormality in their breasts to consult a healthcare professional without delay. CONCLUSION: BSE is not recommended for women in the general population. No recommendation can be established for women aged over 75, those at high risk of breast cancer and those previously treated for breast cancer.

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.

[Non-genetic indications for risk reducing mastectomies: Guidelines of the National College of French Gynecologists and Obstetricians (CNGOF)]. / Indications des mastectomies de réduction de risque en dehors du risque avéré de prédisposition héréditaire : recommandations du Collège national des gynécologues et obstétriciens français (CNGOF).

OBJECTIVE: To determine the value of performing a risk-reducting mastectomy (RRM) in the absence of a deleterious variant of a breast cancer susceptibility gene, in 4 clinical situations at risk of breast cancer. DESIGN: The CNGOF Commission of Senology, composed of 26 experts, developed these recommendations. A policy of declaration and monitoring of links of interest was applied throughout the process of making the recommendations. Similarly, the development of these recommendations did not benefit from any funding from a company marketing a health product. The Commission of Senology adhered to the AGREE II (Advancing guideline development, reporting and evaluation in healthcare) criteria and followed the Grading of Recommendations Assessment, Development and Evaluation (GRADE) method to assess the quality of the evidence on which the recommendations were based. The potential drawbacks of making recommendations in the presence of poor quality or insufficient evidence were highlighted. METHODS: The Commission of Senology considered 8 questions on 4 topics, focusing on histological, familial (no identified genetic abnormality), radiological (of unrecognized cancer), and radiation (history of Hodgkin's disease) risk. For each situation, it was determined whether performing RRM compared with surveillance would decrease the risk of developing breast cancer and/or increase survival. RESULTS: The Commission of Senology synthesis and application of the GRADE method resulted in 11 recommendations, 6 with a high level of evidence (GRADE 1±) and 5 with a low level of evidence (GRADE 2±). CONCLUSION: There was significant agreement among the Commission of Senology members on recommendations to improve practice for performing or not performing RRM in the clinical setting.

TUMOSPEC: A Nation-Wide Study of Hereditary Breast and Ovarian Cancer Families with a Predicted Pathogenic Variant Identified through Multigene Panel Testing.

Assessment of age-dependent cancer risk for carriers of a predicted pathogenic variant (PPV) is often hampered by biases in data collection, with a frequent under-representation of cancer-free PPV carriers. TUMOSPEC was designed to estimate the cumulative risk of cancer for carriers of a PPV in a gene that is usually tested in a hereditary breast and ovarian cancer context. Index cases are enrolled consecutively among patients who undergo genetic testing as part of their care plan in France. First- and second-degree relatives and cousins of PPV carriers are invited to participate whether they are affected by cancer or not, and genotyped for the familial PPV. Clinical, family and epidemiological data are collected, and all data including sequencing data are centralized at the coordinating centre. The three-year feasibility study included 4431 prospective index cases, with 19.1% of them carrying a PPV. When invited by the coordinating centre, 65.3% of the relatives of index cases (5.7 relatives per family, on average) accepted the invitation to participate. The study logistics were well adapted to clinical and laboratory constraints, and collaboration between partners (clinicians, biologists, coordinating centre and participants) was smooth. Hence, TUMOSPEC is being pursued, with the aim of optimizing clinical management guidelines specific to each gene.

Diagnostic chest X-rays and breast cancer risk among women with a hereditary predisposition to breast cancer unexplained by a BRCA1 or BRCA2 mutation.

BACKGROUND: Diagnostic ionizing radiation is a risk factor for breast cancer (BC). BC risk increases with increased dose to the chest and decreases with increased age at exposure, with possible effect modification related to familial or genetic predisposition. While chest X-rays increase the BC risk of BRCA1/2 mutation carriers compared to non-carriers, little is known for women with a hereditary predisposition to BC but who tested negative for a BRCA1 or BRCA2 (BRCA1/2) mutation. METHODS: We evaluated the effect of chest X-rays from diagnostic medical procedures in a dataset composed of 1552 BC cases identified through French family cancer clinics and 1363 unrelated controls. Participants reported their history of X-ray exposures in a detailed questionnaire and were tested for 113 DNA repair genes. Logistic regression and multinomial logistic regression models were used to assess the association with BC. RESULTS: Chest X-ray exposure doubled BC risk. A 3% increased BC risk per additional exposure was observed. Being 20 years old or younger at first exposure or being exposed before first full-term pregnancy did not seem to modify this risk. Birth after 1960 or carrying a rare likely deleterious coding variant in a DNA repair gene other than BRCA1/2 modified the effect of chest X-ray exposure. CONCLUSION: Ever/never chest X-ray exposure increases BC risk 2-fold regardless of age at first exposure and, by up to 5-fold when carrying 3 or more rare variants in a DNA repair gene. Further studies are needed to evaluate other DNA repair genes or variants to identify those which could modify radiation sensitivity. Identification of subpopulations that are more or less susceptible to ionizing radiation is important and potentially clinically relevant.

Gene- and pathway-level analyses of iCOGS variants highlight novel signaling pathways underlying familial breast cancer susceptibility.

Single-nucleotide polymorphisms (SNPs) in over 180 loci have been associated with breast cancer (BC) through genome-wide association studies involving mostly unselected population-based case-control series. Some of them modify BC risk of women carrying a BRCA1 or BRCA2 (BRCA1/2) mutation and may also explain BC risk variability in BC-prone families with no BRCA1/2 mutation. Here, we assessed the contribution of SNPs of the iCOGS array in GENESIS consisting of BC cases with no BRCA1/2 mutation and a sister with BC, and population controls. Genotyping data were available for 1281 index cases, 731 sisters with BC, 457 unaffected sisters and 1272 controls. In addition to the standard SNP-level analysis using index cases and controls, we performed pedigree-based association tests to capture transmission information in the sibships. We also performed gene- and pathway-level analyses to maximize the power to detect associations with lower-frequency SNPs or those with modest effect sizes. While SNP-level analyses identified 18 loci, gene-level analyses identified 112 genes. Furthermore, 31 Kyoto Encyclopedia of Genes and Genomes and 7 Atlas of Cancer Signaling Network pathways were highlighted (false discovery rate of 5%). Using results from the "index case-control" analysis, we built pathway-derived polygenic risk scores (PRS) and assessed their performance in the population-based CECILE study and in a data set composed of GENESIS-affected sisters and CECILE controls. Although these PRS had poor predictive value in the general population, they performed better than a PRS built using our SNP-level findings, and we found that the joint effect of family history and PRS needs to be considered in risk prediction models.

Familial breast cancer and DNA repair genes: Insights into known and novel susceptibility genes from the GENESIS study, and implications for multigene panel testing.

Pathogenic variants in BRCA1 and BRCA2 only explain the underlying genetic cause of about 10% of hereditary breast and ovarian cancer families. Because of cost-effectiveness, multigene panel testing is often performed even if the clinical utility of testing most of the genes remains questionable. The purpose of our study was to assess the contribution of rare, deleterious-predicted variants in DNA repair genes in familial breast cancer (BC) in a well-characterized and homogeneous population. We analyzed 113 DNA repair genes selected from either an exome sequencing or a candidate gene approach in the GENESIS study, which includes familial BC cases with no BRCA1 or BRCA2 mutation and having a sister with BC (N = 1,207), and general population controls (N = 1,199). Sequencing data were filtered for rare loss-of-function variants (LoF) and likely deleterious missense variants (MV). We confirmed associations between LoF and MV in PALB2, ATM and CHEK2 and BC occurrence. We also identified for the first time associations between FANCI, MAST1, POLH and RTEL1 and BC susceptibility. Unlike other associated genes, carriers of an ATM LoF had a significantly higher risk of developing BC than carriers of an ATM MV (ORLoF = 17.4 vs. ORMV = 1.6; p Het = 0.002). Hence, our approach allowed us to specify BC relative risks associated with deleterious-predicted variants in PALB2, ATM and CHEK2 and to add MAST1, POLH, RTEL1 and FANCI to the list of DNA repair genes possibly involved in BC susceptibility. We also highlight that different types of variants within the same gene can lead to different risk estimates.

First case report of an adrenocortical carcinoma caused by a BRCA2 mutation.

BACKGROUND: Adrenocortical carcinoma (ACC) may rarely be a component of inherited cancer syndromes such as Li-Fraumeni syndrome and Beckwith-Wiedemann syndrome. ACC caused by a BRCA2 mutation has never been reported. METHODS: Nucleotide sequencing of BRCA2 in lymphocyte and tumoral DNA of a 50-year-old male who presented with an androgen-secreting ACC and a strong family history of breast, ovarian, and pancreatic cancers. RESULTS: A germline BRCA2 2 bp heterozygous deletion at nucleotide 8765 (8765delAG) leading to a frameshift mutation (p.Glu2846GlyfsX23) was detected. Only the BRCA2 deleted allele was retained in the ACC tumoral DNA compared with the control DNA supporting a loss of heterozygosity in the tumor. CONCLUSION: This is the first reported case of a patient with ACC associated with a BRCA2 germline mutation. Loss of heterozygosity in ACC DNA suggests a causal link with the BRCA2 8765delAG mutation.

[Multidisciplinary team meetings settings on the management of women at high risk of inherited breast cancer. A French study]. / Mise en place des modalités de réunions de concertation pluridisciplinaire pour la prise en charge des patientes prédisposées héréditairement au cancer du sein. Une étude française.

INTRODUCTION: In France, 126 centers for cancer genetics coordinate genetic testing and high-risk cancer surveillance for individuals and their families with hereditary cancer syndromes. Since 2012, the French National Cancer Institute (INCa) supports 17 projects to promote and manage the monitoring of individuals genetically predisposed to cancer. They were assigned 4 missions by INCa including expertise for difficult cases. METHODS: We initiated a national survey to assess how the oncogenetic clinics responded to the 4th mission for women at high risk of developing breast cancers. We sent the survey to all the French oncogeneticists. We aimed at evaluating the modalities and the extent of implementation of the Multidisciplinary team (MDT) meetings regarding the management of women who have genetically higher risks to develop breast cancer. RESULTS: Fourteen people from 12 administrative regions, who represent 10 of the 17 projects, answered the form. Eleven participants reported the submission of medical cases in Oncogenetics MDT meetings (79 %), 5 in senology MDT meetings (36 %), 5 in MDT meetings dedicated to patients at high risk for breast cancer (36 %) and 2 in network meetings (14 %). Some structures discuss medical cases through different MDT meetings. CONCLUSION: Although MDT meetings are valuable practices to optimize treatment or management options for patients, its settings might be subject to difficulties to federate the appropriate-number of participants as well as cost-effectiveness issues. This survey thus suggests the need of a standardized process of MDT meetings while taking account specificities of oncogenetics.

GENESIS: a French national resource to study the missing heritability of breast cancer.

BACKGROUND: Less than 20% of familial breast cancer patients who undergo genetic testing for BRCA1 and BRCA2 carry a pathogenic mutation in one of these two genes. The GENESIS (GENE SISter) study was designed to identify new breast cancer susceptibility genes in women attending cancer genetics clinics and with no BRCA1/2 mutation. METHODS: The study involved the French national network of family cancer clinics. It was based on enrichment in genetic factors of the recruited population through case selection relying on familial criteria, but also on the consideration of environmental factors and endophenotypes like mammary density or tumor characteristics to assess potential genetic heterogeneity. One of the initial aims of GENESIS was to recruit affected sibpairs. Siblings were eligible when index cases and at least one affected sister were diagnosed with infiltrating mammary or ductal adenocarcinoma, with no BRCA1/2 mutation. In addition, unrelated controls and unaffected sisters were recruited. The enrolment of patients, their relatives and their controls, the collection of the clinical, epidemiological, familial and biological data were centralized by a coordinating center. RESULTS: Inclusion of participants started in February 2007 and ended in December 2013. A total of 1721 index cases, 826 affected sisters, 599 unaffected sisters and 1419 controls were included. 98% of participants completed the epidemiological questionnaire, 97% provided a blood sample, and 76% were able to provide mammograms. Index cases were on average 59 years old at inclusion, were born in 1950, and were 49.7 years of age at breast cancer diagnosis. The mean age at diagnosis of affected sisters was slightly higher (51.4 years). The representativeness of the control group was verified. CONCLUSIONS: The size of the study, the availability of biological specimens and the clinical data collection together with the detailed and complete epidemiological questionnaire make this a unique national resource for investigation of the missing heritability of breast cancer, by taking into account environmental and life style factors and stratifying data on endophenotypes to decrease genetic heterogeneity.

Breast Cancer Risk Associated with Estrogen Exposure and Truncating Mutation Location in BRCA1/2 Carriers.

BACKGROUND: Mutations in BRCA1/2 confer a high risk of breast cancer, but literature values of this risk vary. A genotype-phenotype correlation has been found in both genes, and the effect of reproductive factors differs according to mutation location. Therefore, we hypothesize that such a variation may exist for other factors related to estrogen exposure. METHODS: We used a weighted Cox regression model to assess variation in breast cancer risk with these factors using location of mutation in homogeneous breast cancer risk region of BRCA1/2 in the GENEPSO study. RESULTS: We found that late age at menarche reduced breast cancer risk by 31% and that among BRCA1 carriers, a long or a short menstrual cycle increased risk (by 65% and 73%, respectively). Among premenopausal women, overweight was associated with a 45% decrease in risk whereas underweight was associated with an increased risk (HR, 2.40). A natural menopause, mainly after age 50, was associated with a high breast cancer risk (HR, 2.46), and a significant interaction between menopause status and the location of mutations was found leading up to 10% variation in absolute risk according to the age at menopause. CONCLUSIONS: As observed in the general population, a late menarche, a long or a short menstrual cycle, over- or underweight, and being postmenopausal were associated with breast cancer risk in BRCA1/2 carriers. The association with the menopause was observed only when the mutation was located in the "high-risk" zones. IMPACT: Taking into account modifier factors, location of mutation might be important for the clinical management of BRCA1/2 mutation carriers.

Germline BAP1 mutations predispose to renal cell carcinomas.

The genetic cause of some familial nonsyndromic renal cell carcinomas (RCC) defined by at least two affected first-degree relatives is unknown. By combining whole-exome sequencing and tumor profiling in a family prone to cases of RCC, we identified a germline BAP1 mutation c.277A>G (p.Thr93Ala) as the probable genetic basis of RCC predisposition. This mutation segregated with all four RCC-affected relatives. Furthermore, BAP1 was found to be inactivated in RCC-affected individuals from this family. No BAP1 mutations were identified in 32 familial cases presenting with only RCC. We then screened for germline BAP1 deleterious mutations in familial aggregations of cancers within the spectrum of the recently described BAP1-associated tumor predisposition syndrome, including uveal melanoma, malignant pleural mesothelioma, and cutaneous melanoma. Among the 11 families that included individuals identified as carrying germline deleterious BAP1 mutations, 6 families presented with 9 RCC-affected individuals, demonstrating a significantly increased risk for RCC. This strongly argues that RCC belongs to the BAP1 syndrome and that BAP1 is a RCC-predisposition gene.

A focus group study on breast cancer risk presentation: one format does not fit all.

Identifying a strategy that would optimize both the communication and understanding of the individual breast cancer risk remains a considerable challenge. This study explored the preferences of women with a family history of breast cancer about six presentation formats of individual breast cancer risk, as calculated from a risk prediction model. Thirty-four unaffected women attending genetic counseling because of a family history of breast cancer participated in six focus groups conducted in Québec City (2), Montréal (2) and Toronto (2), Canada. Six risk formats were presented for a fictitious case involving a 35-year-old woman (1-numerical: cumulative risk probabilities by age until 80 years; 2-risk curves: probabilities expressed in a risk curve that also provided a risk curve for a woman with no family history in first-degree relatives; 3-relative risk of breast cancer by age 80 years; 4 and 5-absolute risk of breast cancer and absolute chance of not developing breast cancer in the next 20 years; 6-qualitative: color-coded figure). Participants were asked to indicate their appreciation of each format. A group discussion followed during which participants commented on each format. The most and least appreciated formats were risk curves and relative risk, respectively. Overall, participants advocated the use of formats that combine quantitative, qualitative and visual features. Using a combination of approaches to communicate individual breast cancer risks could be associated with higher satisfaction of counselees. Given the increasing use of risk prediction models, it may be relevant to consider the preferences of both the counselee and the professional.

Allelic transcripts dosage effect in morphologically normal ovarian cells from heterozygous carriers of a BRCA1/2 French Canadian founder mutation.

We hypothesized that the transcriptome of primary cultures of morphologically normal ovarian surface epithelial cells could be altered by the presence of a heterozygous BRCA1 or BRCA2 mutation. We aimed to discover early events associated with ovarian carcinogenesis, which could represent putative targets for preventive strategies of this silent killer tumor. We identified the first molecular signature associated with French Canadian BRCA1 or BRCA2 founder mutations in morphologically normal ovarian epithelial cells. We discovered that wild-type and mutated BRCA2 allelic transcripts were expressed not only in morphologically normal but also in tumor cells from BRCA2-8765delAG carriers. Further analysis of morphologically normal ovarian and tumor cells from BRCA1-4446C>T carriers lead to the same observation. Our data support the idea that one single hit in BRCA1 or BRCA2 is sufficient to alter the transcriptome of phenotypically normal ovarian epithelial cells. The highest level of BRCA2-mutated allele transcript expression was measured in cells originating from the most aggressive ovarian tumor. The penetrance of the mutation and the aggressiveness of the related tumor could depend on a dosage effect of the mutated allele transcript.

Comprehensive BRCA1 and BRCA2 mutation analyses and review of French Canadian families with at least three cases of breast cancer.

Few studies have reported on the comprehensive BRCA1/2 mutation analyses of hereditary breast cancer (HBC) families of French Canadian descent. Here we report the investigation of 82 families with at least 3 cases of breast cancer evaluated for mutations by DNA sequencing and/or multiplex ligation-dependent probe amplification (MLPA) assay. DNA sequencing identified pathogenic mutations in 37 (45.1%) families, of which 70.2% were one of three recurring mutations (BRCA1:R1443X, BRCA2:8765delAG, and BRCA2:E1953X) frequently reported in this founder population; and variants of uncertain clinical significance in 7 (8.5%) families of which two harbored BRCA2:E3002K. MLPA analysis of the 38 DNA sequence-negative families did not reveal any large rearrangements in BRCA1/2. A phenotypic characterization of the cancer families based on pathogenic mutation status revealed that there were significantly fewer very young age at diagnosis breast cancer cases (<36 years) in mutation-negative families (5.9%, 9 of 153) than in BRCA1 (22.8%, 13 of 57; P = 0.0003) or BRCA2 (22.9%, 27 of 118; P < 1× 10E5) mutation-positive families. There were significantly more mutation-positive families (29 of 36, 80.6%) with a very young age of onset of breast cancer case than those that did not (8 of 39, 20.5%) (P < 10E6). The comprehensive mutation analysis of BRCA1/2 suggests that genomic rearrangements are unlikely to account for sequence-negative HBC families and affirms that the presence of a very young age of diagnosis of breast cancer is strongly predictive of mutation carrier status of French Canadian HBC families.

Germline TP53 mutations in BRCA1 and BRCA2 mutation-negative French Canadian breast cancer families.

About 40% of French Canadian breast and/or ovarian cancer families harbor germline BRCA1 or BRCA1 mutations where common mutations account for about 84% of all mutations identified in cancer families. Within a series of BRCA1 and BRCA2 mutation-negative families, a germline TP53 13398 G>A (Arg213Gln) mutation was identified, which was selected for mutation analysis in this gene because of a family history consistent with Li-Fraumeni syndrome (LFS). Given the founder effects in this population, the 13398 G>A mutation was screened in series of 52 BRCA1 and BRCA2 mutation-negative cancer families, and a mutation-positive family was identified. However, pedigree inspection and expansion of mutation-positive families with the same mutation revealed that they were closely related to each other. To further characterize the contribution of TP53 in cancer families, mutation analysis was performed in the remaining BRCA1 and BRCA2 mutation-negative cancer families. Thirty sequence variants were identified, the majority of which occur in intronic sequences and are not predicted to affect the functionality of TP53. However, the 14538 G>A (Arg290His) mutation was identified in a family which did not exhibit features consistent with LFS or Li-Fraumeni-like (LFL) syndrome. Neither of the TP53 mutations was detected in 381 French Canadian women with breast cancer diagnosed before 50 years of age not selected for family history of cancer. In all, germline TP53 mutations were identified in two of 52 (3.8%) cancer families, suggesting that TP53 is not a major contributor to BRCA1 and BRCA2 mutation-negative breast and/or ovarian cancer families of French Canadian descent.

Higher frequency of familial clustering of prostate cancer in French-Canadian men.

PURPOSE: Prostate cancer is the second cause of cancer related death in North American men. We investigated the frequency of familial clustering in a French-Canadian population of prostate cancer cases. MATERIALS AND METHODS: Between October 2004 and September 2005, 179 consecutively seen patients with localized prostate cancer identified each of their parents as being of French-Canadian descent. They were asked for their family history of cancer in first-degree relatives, age at diagnosis, whether affected relatives were alive, age and markers of tumor aggressiveness, including prostate specific antigen, Gleason and disease stage. ANOVA was used to compare the distribution of quantitative factors according to qualitative factors identified in our population. Differences between qualitative factors were assessed by the Fisher exact test. All p values were 2-sided. RESULTS: Mean age at diagnosis was 67 years. A total of 45 French-Canadian patients (25.1%) had at least 1 first-degree relative with prostate cancer, including 34 (19%) with 1 first-degree relative, 9 with a father-son pair, 25 with a brother-brother pair and 11 (6.1%) with at least 2 first-degree relatives. In our series the frequency of familial clustering defined by at least 1 relative with prostate cancer was high. We found a higher percent of French-Canadian men with at least 1 first-degree relative with prostate cancer than what was previously reported for an unselected population in Canada (25.1% vs 14.7%, p <0.0001). CONCLUSIONS: Those preliminary results open a new perspective to a better understanding of familial prostate cancer in the Province of Quebec.

A review of histopathological subtypes of ovarian cancer in BRCA-related French Canadian cancer families.

Pathogenic mutations in BRCA1 and BRCA2 have been reported in about 55-59% of breast and ovarian cancer (HBOC) families of French Canadian descent, where about 70% of families with more than two cases of ovarian cancer were mutation-positive. Given that specific subtypes of ovarian cancer are associated with mutation-positive families, we reviewed the features of 54 HBOC families of French Canadian descent that had histopathologically confirmed cases of invasive ovarian cancer where the BRCA1 and BRCA2 mutation status is known, and 27 families harbored germline mutations. The number of cases and ages of diagnosis of either breast cancers or ovarian cancers did not differ significantly in comparisons of mutation-positive and mutation-negative groups. However, the distribution of histopathological subtypes for the 79 cases of invasive epithelial cancer from the 54 HBOC families differed when grouped according to familial mutation status. The mutation-negative group had significantly more cases of the mucinous subtype of ovarian cancer when compared with the BRCA1 (P = 0.005) and BRCA2 (P = 0.017) mutation-positive groups. The presence of a mucinous subtype ovarian cancer in multiple young age of onset breast and/or ovarian mutation-negative HBOC cancer families warrants further investigation, as these families appear to exhibit features most consistent with BRCA1 and BRCA2 carrier status.