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The genetic predisposition to familial hematological malignancies has been previously reported highlighting inherited gene mutations. Several genes have been reported but genetic basis remains not well defined. In this study, we extended our investigation to a potential candidate GATA2 gene which was analyzed by direct sequencing in 119 cases including familial aggregations with a variety of hematological malignancies and sporadic acute leukemia belonging to Tunisian and French populations. We reported a deleterious p.Arg396Gln GATA2 mutation in one patient diagnosed with both sporadic acute myeloid leukemia (AML) and breast cancer. We also reported several GATA2 variations in familial cases. The absence of deleterious mutations in this large cohort of familial aggregations of hematological malignancies may strengthen the hypothesis that GATA2 mutations are an important predisposing factor, although as a secondary genetic event, required for the development of overt malignant disease. [ABSTRACT FROM AUTHOR]

Mutations are responsible for familial cancer syndromes which account for approximately 5-10 % of all types of cancers. Familial cancers are often caused by genetic alterations occurring either in tumor suppressor or genomic stability genes such as TP53. In this study, we have analyzed the TP53 gene by direct sequencing approach, in a panel of 18 Tunisian familial hematological malignancies cases including several forms of leukemia, lymphoma and myeloid syndrome and 22 cases of sporadic acute leukemia. In one familial case diagnosed with acute lymphoblastic leukemia, we reported an intronic substitution 559+1 G>A which may disrupt the splice site and impact the normal protein function. Most of the deleterious mutations (Arg158His; Pro282Trp; Thr312Ser) as classified by IARC data base, were commonly reported in ALL cases studied here. The cosegregation of the two variants rs1042522 and rs1642785 was observed in most patients which may be in favor of the presence of linkage disequilibrium. The most defined TP53 mutations found here were identified in acute lymphoblastic leukemia context whereas only 3 % of mutations have been in previous studies. The cosegregation of the two recurrent variant rs1042522 and rs1642785 should be further confirmed. [ABSTRACT FROM AUTHOR]

Ovarian neoplasms secondary to germline BRCA mutations had been described to have a more favourable survival. There is only few data concerning the prognosis of non mutated patients presenting clinical features evocative of BRCA alterations. We retrospectively collected data from patients treated in our institution for an invasive ovarian carcinoma between 1995 and 2011. Patients considered at high risk of BRCA mutation were tested for BRCA1/2 germline mutations. We described clinical, pathological and therapeutic features and compared prognosis of BRCA mutation carriers and non-mutated patients. Out of 617 ovarian cancer patients, we identified 104 patients who were considered at high risk of mutation. The 33 mutated patients were more likely to present a personal (33 vs. 10 %, p = 0.003) or a family (42 vs. 24 %, p = 0.06) history of breast/ovarian cancers. BRCA1/2 mutation carriers and wild type patients displayed similar prognosis: median progression-free survival (PFS) of 20.9 versus 37.7 months ( p = 0.21); median overall survival (OS) of 151.2 versus 122.5 months ( p = 0.52). Personal history of breast cancer increased both PFS [HR = 0.45 (95CI 0.25-0.81)] and OS [HR = 0.35 (95CI 0.16-0.75)]. In multivariate analysis, this parameter was an independent prognostic feature, whereas the identification of a BRCA1/2 mutation was not. In our cohort, all patients at high risk of BRCA mutation share a similar prognosis, whatever is their germline mutation status. Prognosis seems to be more influenced by clinical history than by germline mutations identification. If it is confirmed in larger and independent series, this result suggests that the hypothesis of other BRCA pathway alterations (BRCAness phenotype) deserves to be deeply explored. [ABSTRACT FROM AUTHOR]

Familial aggregation of hematological malignancies has been reported highlighting inherited genetic predisposition. In this study, we targeted four candidate genes: JAK2 and RUNX1 genes assuring a prominent function in hematological process and CBL and NPM1 as proto-oncogenes. Their disruption was described in several sporadic hematological malignancies. The aim of this study is to determine whether JAK2, CBL, RUNX1, and NPM1 germline genes mutations are involved in familial hematological malignancies. Using direct sequencing, we analyzed JAK2 (exons 12 and 14); CBL (exons 7, 8 and 9); NPM1 (exon 12) and the entire RUNX1 in 88 independent families belonging to Tunisian and French populations. Twenty-one sporadic acute leukemias were included in this study. We reported a heterozygous intronic c.1641 + 6 T > C JAK2 variant (rs182123615) found in two independent familial cases diagnosed with gastric lymphoma and Hodgkin lymphoma. The in silico analysis suggested a potential impact on splicing, but the functional splicing minigene reporter assay on rs182123615 variant showed no aberrant transcripts. In one sporadic acute myeloblastic leukemia, we reported an insertion 846 in. TGTT in exon 12 of NPM1 gene that may impact the normal reading frame. The rs182123615 JAK2 variant was described in several contexts including myeloproliferative neoplasms and congenital erythrocytosis and was supposed to be pathogenic. Through this current study, we established the assessment of pathogenicity of rs182123615 and we classified it rather as rare polymorphism. [ABSTRACT FROM AUTHOR]

The genetic counselling profession was established in France in 2004. Eight years later, 122 genetic counsellors have graduated from the unique educational French program which awards the Professional Master Degree of Human Pathology, entitled 'Master of Genetic Counselling and Predictive Medicine'. As part of a global evaluation of this new profession by health genetic professionals, we undertook a national survey investigating various aspects such as employment, work responsibilities and integration. To our knowledge, this is the first study to investigate the views of genetic professionals on the genetic counsellors' role. Of 422 French professionals invited to take part in this study, 126 participated. The survey underlines that this profession is significantly recognized by physicians practicing within genetics departments. French genetic counsellors are allowed to manage consultations independently, without the necessary presence of a qualified medical geneticist but under his or her responsibility. Genetic counsellors participate in a wide range of consultations. They provide both information for relevant and for genetic testing and sometimes disclose the genetic test result to patient. Eventually, the role of genetic counsellors appears to be directly dependent from the relationship of trust between the two health professions. [ABSTRACT FROM AUTHOR]

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) 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. [ABSTRACT FROM AUTHOR]

Objective: Evidence-based counseling and prevention are not available so far for hereditary cancer prone persons, since we lack data based on clinical trials. There are very few high-risk persons in the population as a whole. Based on a familial history analysis, only 1.2% of all healthy volunteers attending screening centers reached the arbitrary high-risk level defined as a Relative Risk of more than 4. We describe a randomized trial based on colonoscopic screening for colorectal cancer on a sub-group of high-risk group persons. Materials and methods:Among the 77 members of the French Institutional Preventive Center Network, 37 took part in this protocol. During the first 3 years, 850,000 persons were interviewed at these 37 Health centers. The enrolment process was particularly time-consuming, since a large amount of information had to be delivered to the participants. Results: The mean rate of recruitment of eligible candidates was far lower than predicted, averaging only 1.4 per 1,000 persons interviewed instead of the 9/1,000 expected. This mean figure was based, however, on inclusion rates ranging from 0.06/1,000 to 7/1,000 among the different centers. The low rates of recruitment were mainly due to the inter-center heterogeneity (differences in commitment and in the resources), and to the fact that the acceptability of undergoing a colonoscopy turned out to be lower than predicted. Conclusion: Population trials on cancer prone persons are feasible, but vast numbers have to be pre-screened to identify the few people with a high hereditary risk and willing to accept screening within a controlled trial. [ABSTRACT FROM AUTHOR]

Prophylactic surgery is a major issue for breast/ovarian cancer prone women. Bio-clinical data to help in the decision-making are not sufficient. In this context of uncertainty, physicians' and women's attitudes to prophylactic surgery is information of great value. The physicians' attitudes were assessed by a randomised national sample of practitioners involved in breast and ovarian cancer management. The patients' attitudes were appraised with a pre-consultation self-administered questionnaire presented during a one-year period to all women in five cancer genetic clinics chosen, for their representative geographical locations and their activity level. Consent to prophylactic surgery is higher among physicians than among patients ( p < 0.0001). Acceptability of mastectomy is lower than that of oophorectomy in both patients and physicians ( p < 0.0001 in both groups). In addition, age at which the intervention is proposed to be performed is a key determinant for both mastectomy and oophorectomy acceptability, in both physicians and patients ( p < 0.001 for each comparison). Particularly, the age of 40 years seems to be a critical threshold for the acceptability of prophylactic oophorectomy. In contrast, respondents' age at the time of the survey has no significant effect on the acceptability rate. The higher acceptability rate of prophylactic oophorectomy compared to that of mastectomy observed in the physicians' survey is paradoxical because a more substantial medical impact on life expectancy was expected from the latter. Our results indicate that assumed reduced mortality is not the main criterion steering acceptability. It was anticipated that prophylactic mastectomy should be rarely performed in France. [ABSTRACT FROM AUTHOR]

After a BRCA mutation has been identified in the context of hereditary breast/ovarian cancer (HBOC), mammographic screening and prophylactic surgery are two of the main options available to those responsible for the clinical management of healthy women. The aim of this study was to describe the attitudes of specialists towards the clinical management of women with an HBOC risk: this information was collected prior to the publication of the recent French guidelines. A random national sample of 1169 French surgeons, gynaecologists and obstetricians was surveyed using a mailed questionnaire, to which 700 of these physicians (60%) responded. When dealing with a BRCA mutated woman, 88.6% of the respondents said they would recommend mammographic screening, but only 27.1% would recommend that it should be carried out annually from the age of 30 years onwards, as recommended in the French guidelines; 10.9% would find it acceptable to propose prophylactic mastectomy from the age of 30 years, and 22.9% would find it acceptable to propose prophylactic oophorectomy from the age of 35 years. The specialists who agreed with recommending breast/ovarian cancer genetic testing also had more positive attitudes towards prophylactic mastectomy (adj OR = 3.4, 95% CI = 1.4-8.2), as did those who had previously recommended prophylactic mastectomy when gene testing was not yet available (adj OR = 2.06, 95% CI = 1.23-3.44). The respondents' attitudes towards prophylactic oophorectomy and mastectomy were significantly associated (adj OR = 3.9; 95% CI = 2.3-6.5). Previous recommendation of prophylactic mastectomy was associated (P < 0.01) with a higher level of knowledge of breast/ovarian cancer genetics and with medical practice in this field. French physicians' attitudes towards mammographic screening and prophylactic surgery were not in complete agreement with the subsequently published French guidelines, the impact of which has now to be considered. Constantly evolving knowledge... [ABSTRACT FROM AUTHOR]

To appreciate the involvement of known or potential susceptibility genes in sporadic breast tumors, we have searched for chromosomal deletions by studying loss of heterozygosity (LOH) at 43 microsatellite (CA)n markers from human chromosomes 10, 11 and 17, in 115 unselected consecutive samples of breast carcinoma with particular emphasis on specific regions. No site of consistent LOH was identified on chromosome 10. Five regions of LOH were contained within bands q22-24 of chromosome 11 for which nearly 50% of the tumors had LOH at at least one marker. This region is thus a major site of deletion in breast cancer and several tumor suppressor genes seem to be involved. One of them may be the ataxia telangiectasia (ATM) gene which is located in one of the affected regions. Five regions of LOH, one of which is within the BRCA1 gene area, were recognized along chromosome 17. LOH at three of these regions were found in highly proliferative tumors. When combined with a previous study of chromosome 13 with emphasis on BRCA2 and Rb1 genes, this work allowed to distinguish a total of 12 regions of LOH, variably affected in breast tumors and correlated with prognostic parameters. [ABSTRACT FROM AUTHOR]

The use of polymorphic DNA segments as markers for the gene for the multiple endocrine neoplasia (MEN) syndrome, type 2a, allows the identification of family members at high risk for developing medullary carcinoma of the thyroid and other tumors, especially pheochromocytoma. Several families have also been identified in which medullary thyroid carcinoma is inherited, but pheochromocytoma is not seen. We have analysed 18 families, 9 with MEN 2A and 9 with medullary carcinoma of the thyroid without pheochromocytoma, with probes specific for the pericentromeric region of chromosome 10 and conclude that the mutations for the two presentations are closely situated. Genetic heterogeneity of the susceptibility locus was not seen among this sample of 18 families. The genetic mutation for medullary carcinoma was in disequilibrium with the marker alleles of the two closely linked probes. IRBPH4 and MCK2. These data suggest that different mutant alleles of the same gene or closely linked mutations account for the variation in penetrance of pheochromocytoma in families with hereditary, medullary thyroid carcinoma. [ABSTRACT FROM AUTHOR]

A gene for early-onset familial breast cancer has recently been mapped to the chromosome 17q12-23 region. In order to confirm the gene location, we have tested an extensive early-onset breast cancer family with 4 markers in this chromosome region. Linkage was negative with all 4 markers. This study suggests that there is genetic heterogeneity among early-onset breast cancer families. [ABSTRACT FROM AUTHOR]

We have examined 30 families with multiple endocrine neoplasia type 2a (MEN2A). Linkage studies indicate that the gene for MEN2A is located on chromosome 10, tightly linked to the D10Z1 locus. [ABSTRACT FROM AUTHOR]