Screening in breast cancer families: is it useful?

Somatic Mutations and Altered Expression of the Candidate Tumor SuppressorsCSNK1ε,DLG1, andEDD/hHYDin Mammary Ductal Carcinoma

We report somatic mutations in three genes (CSNK1 epsilon, encoding the Ser/Thr kinase casein kinase I epsilon; DLG1, encoding a membrane-associated putative scaffolding protein; and EDD/hHYD, encoding a progestin induced putative ubiquitin-protein ligase) in mammary ductal carcinoma. These genes were suspected of playing a role in cancer because loss-of-function mutations in their Drosophila homologues cause excess tissue growth. Using DNA from 82 laser-microdissected tumor samples, followed by microsatellite analysis, denaturing HPLC and direct sequencing, we found multiple somatic point mutations in all three genes, and these mutations showed significant association with loss of heterozygosity of closely linked polymorphic microsatellite markers. For CSNK1 epsilon and DLG1, most of the mutations affected highly conserved residues, some were found repetitively in different patients, and no synonymous mutations were found, indicating that the observed mutations were selected in tumors and may be functionally significant. Immunohistochemical reactivity of each protein was reduced in poorly differentiated tumors, and there was a positive association between altered protein reactivity, loss of heterozygosity, and somatic mutations. There was a statistically significant association of hDlg staining with p53 and Ki67 reactivity, whereas CSK1 epsilon and EDD/hHYD staining levels were associated with progesterone receptor status. The results provide strong indications for a role of all three genes in mammary ductal carcinoma. They also justify additional studies of the functional significance of the changes, as well as a search for additional changes in these and other genes identified from studies on model systems.

Breast cancer screening, diagnosis, and treatment

The incidence of breast cancer in US women remains disturbingly high, and unfortunately primary care physicians still frequently encounter patients in whom the disease is suspected or, even worse, confirmed. Fortunately, however, the body of knowledge surrounding the disease has grown dramatically during the past decade, and major advances have been made in the understanding of breast cancer risk, prevention, diagnosis, and treatment. Controversies persist, particularly those concerning the screening of younger women, but consensus now exists regarding many clinical issues relevant to primary care practice. Although multidisciplinary subspecialty expertise must be made available to all women with known or suspected breast cancer, the primary care physician has an important role to play when dealing with patients with this condition. The following article focuses on what primary care practitioners need to know to expertly contribute to the diagnosis, counseling, and initial treatment of women with this disease.

Recommendations for medical management of hereditary breast and ovarian cancer: the French National Ad Hoc Committee

BACKGROUND AND PURPOSE

Almost 10% of breast and ovarian cancers are familial, and the majority are linked to BRCA1 and BRCA2 germline mutations. Despite uncertainty about the management of female gene carriers, consensus guidelines have been established to assist practitioners and consultees in making health care decisions.

METHODOLOGY

The Ad Hoc Committee was composed of 14 experts appointed by the French National Institute for Health and Medical Research, all of whom attended eleven workshops at which more than 3500 articles were systematically analyzed. Five additional experts critically analysed the first version of the report. CRITERIA AND DECISION PROCESS: On a probability scale of the risk of developing breast or ovarian cancers, two thresholds were defined for use in determining whether an intervention would be worthwhile. The first is the threshold above which an intervention can be envisaged or recommended, and the second is the one below which an intervention can be ruled out; between the two, the decision has to be made on a case-by-case basis. SCREENING AND PREVENTIVE STRATEGIES ANALYZED: With respect to breast cancer: 1) hormonal interventions; 2) primary prevention (diet, family planning and chemoprevention); 3) screening (breast self-examination, clinician breast examination, tumor markers, imaging); 4) prophylactic mastectomy. With respect to ovarian cancer: 1) hormonal stimulation; 2) screening (clinical screening, ultrasound and tumor markers); 3) prophylactic oophorectomy.

MAIN CONCLUSIONS

For each strategy the following points were addressed: the information to be given to the consultee, the procedure and the indications. In addition, the committee's opinion about BRCA1 and BRCA2 mutation screening is that population-based, or even large-scale, implementation are not justified. Although no scientific evidence is available, the committee feels that specific management is indispensable and advocates the use of defined and evaluated procedures, and participation in clinical trials.

Attitudes towards cancer predictive testing and transmission of information to the family

Before the organisation of breast cancer predictive testing in France, consultands' attitudes towards this kind of testing and towards passing on information about the family cancer risk to their relatives were investigated. This survey was carried out from January 1994 to January 1995 at six specialised cancer genetic clinics located in different parts of France Female consultands who were first degree relatives of cancer patients and who had at least one case of breast cancer in their family, affecting either themselves or a first degree relative or both, participated in this study. Among the 248 eligible consultands attending the clinics during the study period, 84.3% answered a post-consultation questionnaire. Among the 209 respondents, 40.7% (n = 85) were cancer patients and 59.3% (n = 124) were healthy consultands. A high consensus in favour of genetic testing was noted, since 87.7% of the sample stated that they would ask for breast cancer gene testing if this test became available. The underlying assumption of 96.6% of the women was that their health surveillance would be improved after a positive test. A high awareness of the anxiety that would be generated in a family after a positive result was observed and found to be associated (p < 0.05) with the anxiety and depressive profiles of the patients. Half of the healthy respondents said they would not change their attitude towards screening if the results of predictive testing turned out to be negative. Only 13.7% of the 161 patients who stated that the oncogeneticists asked them to contact their relatives firmly refused to do so, mainly because of difficult family relationships.

Inherited breast cancer

Five to ten percent of breast cancer is attributable to the autosomal dominant inheritance of a high-risk susceptibility gene. There are a number of known inherited cancer syndromes that confer a higher risk of breast cancer. Recently, the BRCA1 gene, which is responsible for 45% of hereditary early-onset breast cancer and for the majority of co-inheritance of breast and ovarian cancer, has been cloned. Another gene that confers an increased risk of breast cancer is the BRCA2 gene, which maps to the long arm of chromosome 13 by linkage analysis. Mutations in BRCA2 account for approximately 40% of hereditary early-onset breast cancer. In addition, at least 7% of breast cancer may occur in women who are heterozygous for mutations in a gene for ataxia-telangiectasia, an autosomal recessive chromosome instability syndrome. Predictive testing for some predisposing conditions is possible through indirect or direct mutation testing. In this article, the genetics of breast cancer are reviewed, and practical concerns for the surgeon in counseling high-risk patients are addressed.

Cancer genetics clinics: target population and consultees' expectations

The aim of this study was to determine in healthy consultees attending cancer genetics clinics their risk status, their pathways leading to the clinics, their expectations and perception of cancer risk. In 1994, the consultees at six French centres completed a questionnaire before their first oncogenetic consultation. The oncogeneticists subsequently filled in a standardised form giving their risk assessment. Among the 206 healthy consultees, 91.3% were women, 92.2% had at least one cancer-affected first-degree relative and 73% had a "cancer family risk" as assessed by the oncogeneticist. Sixty-nine per cent of the consultees were referred to the clinics by a physician, 10.4% by their family and 18.8% on their own initiative: 83.5% of the sample perceived their family risk of cancer as being high and this belief was confirmed in 74.3% of the cases studied by the oncogeneticist. The families of self-referred consultees were less often at risk than those of consultees referred by a physician or by their family (P = 0.012). The majority (78%) expected to be informed about cancer prevention and screening, and this expectation depended on the consultee's level of education (P = 0.001). This study shows that medical pathways are more effective than the media as a means of reaching the members of the general population who are genuinely at risk, and shows that fuller information about prevention needs to be provided at cancer genetic consultations.

Molecular genetics of familial breast-ovarian cancer

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