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H Sobol

Publications and source records attributed to H Sobol.

At least 19 recordsLinked to original sources
PubMed2006

[Identification and management of HNPCC syndrome (hereditary non polyposis colon cancer), hereditary predisposition to colorectal and endometrial adenocarcinomas].

BACKGROUND: The HNPCC syndrome (hereditary nonpolyposis colon cancer) is an inherited condition defined by clinical and genealogical information, known as Amsterdam criteria. In about 70% of cases, HNPCC syndrome is caused by germline mutations in MMR genes, leading to microsatellite instability of tumor DNA (MSI phenotype). Patients affected by the disease are at high risk for colorectal and endometrial carcinomas, but also for small intestine, urothelial, ovary, stomach and biliary tract carcinomas. HNPCC syndrome is responsible for 5% of colorectal cancers. Identification and management of this disease are part of a multidisciplinary procedure. METHODS: Twelve experts have been mandated by the French Health Ministry to analyze and synthesize their consensus position, and the resulting document has been reviewed by an additional group of 4 independent experts. MAIN RECOMMENDATIONS: The lack of sensitivity of Amsterdam criteria in recognizing patients carrying a MMR germline mutation led to an enlargement of these criteria for the recruitment of possible HNPCC patients, and to a 2-steps strategy, asking first for a tumor characterization according to MSI phenotype, especially in case of early-onset sporadic cases. The identification of germline MMR mutations has no major consequence on the cancer treatments, but influences markedly the long-term follow-up and the management of at-risk relatives. Gene carriers will enter a follow-up program regarding their colorectal and endometrial cancer risks, but other organs being at low lifetime risk, no specific surveillance will be proposed.

Adenocarcinoma↗
PubMed2006

[Identification and management of hereditary breast-ovarian cancers (2004 update)].

BACKGROUND: Since the last recommendations, up to 2500 new references had been published on that topic. METHODOLOGY: On the behalf of the health Minister, the Ad Hoc Committee consisted of 13 experts carried out a first version revisited by five additional experts who critically analyzed the first version of the report. MAIN UPDATING: Breast and ovarian cancer seem to be associated with fewer deleterious mutations of BRCA1 and BRCA2 than previously thought. The screening of ovarian cancer is still not an attractive option while in contrast MRI may be soon for these young women with dense breast, the recommended option for breast cancer screening. The effectiveness of prophylactic surgeries is now well established. French position is to favor such surgeries with regard to a quality of life in line with the expected benefit, and providing precise and standardized process described in the recommendation. CONCLUSIONS: Due to methodological flaws, the low power and a short follow-up of the surveys, this statement cannot however aspire to a high stability.

Breast Neoplasms↗
PubMed2006

The contribution of germline rearrangements to the spectrum of BRCA2 mutations.

BACKGROUND: Few germline BRCA2 rearrangements have been described compared with the large number of germline rearrangements reported in the BRCA1 gene. However, some BRCA2 rearrangements have been reported in families that included at least one case of male breast cancer. OBJECTIVE: To estimate the contribution of large genomic rearrangements to the spectrum of BRCA2 defects. METHODS: Quantitative multiplex PCR of short fluorescent fragments (QMPSF) was used to screen the BRCA2 gene for germline rearrangements in highly selected families. QMPSF was previously used to detect heterozygous deletions/duplications in many genes including BRCA1 and BRCA2. RESULTS: We selected a subgroup of 194 high risk families with four or more breast cancers with an average age at diagnosis of < or = 50 years, who were recruited through 14 genetic counselling centres in France and one centre in Switzerland. BRCA2 mutations were detected in 18.6% (36 index cases) and BRCA1 mutations in 12.4% (24 index cases) of these families. Of the 134 BRCA1/2 negative index cases in this subgroup, 120 were screened for large rearrangements of BRCA2 using QMPSF. Novel and distinct BRCA2 deletions were detected in three families and their boundaries were determined. We found that genomic rearrangements represent 7.7% (95% confidence interval 0% to 16%) of the BRCA2 mutation spectrum. CONCLUSION: The molecular diagnosis of breast cancer predisposition should include screening for BRCA2 rearrangements, at least in families with a high probability of BRCA2 defects.

Exons↗
PubMed2005

[HNPCC syndrome (hereditary non polyposis colon cancer): identification and management].

BACKGROUND: The hereditary non-polyposis colon cancer (HNPCC) syndrome is an inherited condition defined by clinical and genealogical information, known as Amsterdam criteria. In about 70% of cases, HNPCC syndrome is caused by germline mutations in MMR genes, leading to microsatellite instability of tumor DNA (MSI phenotype). Patients affected by the disease are at high risk for colorectal and endometrial carcinomas, but also for other organs tumors. HNPCC syndrome is responsible for 5% of colorectal cancers. MAJOR ASPECTS: The lack of sensitivity of Amsterdam criteria in recognizing patients carrying a MMR germline mutation led to an enlargement of these criteria for the recruitment of possible HNPCC patients, and to a two-steps strategy, asking first for a tumor characterization according to MSI phenotype, especially in case of early-onset sporadic cases. FURTHER DEVELOPMENTS: The identification of germline MMR mutations has no major consequence on the cancer treatments, but influences markedly the long-term follow-up and the management of at-risk relatives. Gene carriers will enter a follow-up program regarding their colorectal and endometrial cancer risks; other organs being at low lifetime risk, no specific surveillance will be proposed.

Adolescent↗
PubMed2004

[Molecular alterations in breast cancer: clinical implications and new analytical tools].

PURPOSE: Breast cancer is a complex and heterogeneous disease resulting from various molecular alterations, the identification of which should have profound impact on the management of patients. CURRENT KNOWLEDGE AND KEY POINTS: The discovery of germline mutations within breast cancer susceptibility genes, such as BRCA1 and BRCA2, which are associated with a major risk of breast cancer during lifetime, has improved the assessment of the individual risk toward the disease, allowing appropriate strategies of screening and prevention. The identification of key molecular actors in the mammary oncogenesis may help to better assess the prognosis of the disease, while providing new therapeutic targets. Large-scale molecular technologies, which allow simultaneous assessment of a high number of molecular parameters in a single assay, should provide new tools to tackle complexity and heterogeneity of breast cancer. Hence, by examining transcriptional profiles of breast cancer using DNA microarrays, it was possible to reveal new prognostic tumor subgroups, previously indistinguishable. Further improvements are awaited with the recent development of high throughput and large-scale technologies investigating the tumor proteome. PROSPECTS AND PROJECTS: Precise knowledge of molecular alterations involved in each individual breast cancer will allow more effective and less toxic, tailored therapies.

Breast Neoplasms↗
PubMed2004

Prevention and genetic testing for breast cancer: variations in medical decisions.

The discovery linking the genes BRCA1&2 to familial breast cancer played an important role in the clinical practice of geneticists and physicians. The availability of genetic tests for BRCA gene mutations prompted cancer geneticists to give information about genetic risk and to assess many women with a personal or family history of breast or ovarian cancer to inform them of preventive measures. These consist mainly of breast self-examination, mammography screening, chemoprevention and prophylactic surgery (mastectomy, oophorectomy). This paper examines clinical practices related to hereditary breast cancer testing and introduces a number of results from a survey carried out, between 1996 and 1998, in three clinics located in Montreal (Quebec, Canada), Marseilles (France) and Manchester (Great Britain). Results show substantial differences in the way cancer geneticists deal with environmental risk factors, breast and ovarian cancer testing, and chemoprevention and prophylactic surgery. Differences across cities persist in the multivariate analysis, suggesting that attitudes towards preventive measures may be partially explained by cultural factors. Different dimensions of culture are discussed including the social representation of health and risk, the interpretation of scientific evidence and the role of innovation leadership.

Adolescent↗
PubMed2003

Cancer genetics service provision: a comparison of seven European centres.

OBJECTIVE: To conduct a survey in seven European cancer genetics centres to compare service provision, organisation and practices for familial breast and colon cancer consultations and testing. Information was obtained on aspects of services both nationally and locally. METHODS: A detailed survey questionnaire was adapted collaboratively to obtain the required information. Initial survey data were collected within each centre and interim results were discussed at two European Workshops. Where differences in practice existed, details were clarified to ensure accuracy and adequacy of information. Participating centres were Haifa (Israel), Hannover (Germany), Leiden (The Netherlands), Leuven (Belgium), Manchester (UK), Marseille (France) and Milan (Italy), representing countries with populations ranging from 6.5 to 80 million. RESULTS: The European countries diverged in regard to the number of cancer genetics centres nationally (from 8 in Belgium to 37 in France), and the average population served by each centre (from 0.59 million in Israel to 3.32 million in Italy). All centres offered free care at the point of access, but referral to specialist care varied according to national health care provision. At a centre level, staff roles varied due to differences in training and health care provision. The annual number of counsellees seen in each participating centre ranged from 200 to over 1,700. Access to breast surveillance or bowel screening varied between countries, again reflecting differences in medical care pathways. These countries converged in regard to the wide availability of professional bodies and published guidelines promoting aspects of service provision. Similarities between centres included provision of a multidisciplinary team, with access to psychological support, albeit with varying degrees of integration. All services were dominated (70-90%) by referrals from families with an increased risk of breast cancer despite wide variation in referral patterns. Collection of pedigree data and risk assessment strategies were broadly similar, and centres used comparable genetic testing protocols. Average consultation times ranged between 45 and 90 min. All centres had access to a laboratory offering DNA testing for breast and bowel cancer-predisposing genes, although testing rates varied, reflecting the stage of service development and the type of population. Israel offered the highest number of genetic tests for breast cancer susceptibility because of the existence of specific founder mutations, in part explaining why the cancer genetics service in Haifa differed most from the other six. CONCLUSION: Despite considerable differences in service organisation, there were broad similarities in the provision of cancer genetic services in the centres surveyed.

Breast Neoplasms↗
PubMed2003

Information-seeking behaviour and psycho-social interactions during the genetic testing process.

OBJECTIVES: The first aim of this study was to investigate the information-seeking behaviour (ISB) of women attending cancer genetic consultations at which the possibility of BRCA testing is considered. We focused here specifically on ISB apart from the cancer genetic consultation, i.e. on what complementary sources of information about genetic testing were consulted and what factors were involved in this behaviour. The second aim was to study the role of the social network used by the patients to collect various opinions on which to base their decisions about being tested. METHODS: A prospective cohort study (2000-2002) was therefore carried out on all women attending a single cancer genetic clinic in France after a BRCA1/2 analysis had been proposed. Closed questionnaires were administered before and after the second cancer genetic consultation. The purpose of this consultation was to confirm the patient's decision to be tested. RESULTS: Results were analysed in 108 subjects (mean age 47 years, SD 11 years; 74% affected by breast/ovarian cancer). Prior to the 2nd consultation, 35.2% of the women had actively looked for information about BRCA1/2 testing, as compared to 25.0% afterwards. After multivariate adjustment by logistic regression, the pre-consultation ISB was found to be associated with greater satisfaction with the information about the psycho-social consequences of genetic testing [adjusted odds ratio (ORadj) 1.03, 95% confidence interval (CI) 1.01-1.06] (scale from 0 to 100) and about the certainty of being a gene carrier (ORadj 3.04, 95% CI 1.16-7.98). Those who actively looked for complementary information were also more often accompanied at the consultation by a family member (ORadj 4.82, 95% CI 1.85-12.56). The other variables tested (depression, coping, socio-demographic and medical characteristics) were not significant (p > 0.05). The role of the social network in the decision making process was perceived as being less helpful when the persons consulted tended to have neutral or unfavourable opinions about genetic testing. CONCLUSIONS: Few women actively sought complementary information about BRCA genetic testing in addition to the cancer genetic consultation. Those who did so differed from the others in terms of their social network and their satisfaction with the consultation. The cancer geneticist is the key actor in women's decision making about genetic testing.

Attitude to Health↗
PubMed2001

Localization of a susceptibility gene for familial nonmedullary thyroid carcinoma to chromosome 2q21.

The familial form of nonmedullary thyroid carcinoma (NMTC) is a complex genetic disorder characterized by multifocal neoplasia and a higher degree of aggressiveness than its sporadic counterpart. In a large Tasmanian pedigree (Tas1) with recurrence of papillary thyroid carcinoma (PTC), the most common form of NMTC, an extensive genomewide scan revealed a common haplotype on chromosome 2q21 in seven of the eight patients with PTC. To verify the significance of the 2q21 locus, we performed linkage analysis in an independent sample set of 80 pedigrees, yielding a multipoint heterogeneity LOD score (HLOD) of 3.07 (alpha=0.42), nonparametric linkage (NPL) 3.19, (P=.001) at marker D2S2271. Stratification based on the presence of at least one case of the follicular variant of PTC, the phenotype observed in the Tas1 family, identified 17 such pedigrees, yielding a maximal HLOD score of 4.17 (alpha=0.80) and NPL=4.99 (P=.00002) at markers AFMa272zg9 and D2S2271, respectively. These results indicate the existence of a susceptibility locus for familial NMTC on chromosome 2q21.

Carcinoma, Papillary↗
PubMed2001

Comparison of physicians' and cancer prone women's attitudes about breast/ovarian prophylactic surgery. Results from two national surveys.

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.

Adult↗
PubMed2001

Cancer prone persons. A randomized screening trial based on colonoscopy: background, design and recruitment.

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 enrollment 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.

Adolescent↗