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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(-3)) 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.

The c.156&#95;157insAlu BRCA2 mutation has so far only been reported in hereditary breast/ovarian cancer (HBOC) families of Portuguese origin. Since this mutation is not detectable using the commonly used screening methodologies and must be specifically sought, we screened for this rearrangement in a total of 5,443 suspected HBOC families from several countries. Whereas the c.156&#95;157insAlu BRCA2 mutation was detected in 11 of 149 suspected HBOC families from Portugal, representing 37.9% of all deleterious mutations, in other countries it was detected only in one proband living in France and in four individuals requesting predictive testing living in France and in the USA, all being Portuguese immigrants. After performing an extensive haplotype study in carrier families, we estimate that this founder mutation occurred 558 ± 215 years ago. We further demonstrate significant quantitative differences regarding the production of the BRCA2 full length RNA and the transcript lacking exon 3 in c.156&#95;157insAlu BRCA2 mutation carriers and in controls. The cumulative incidence of breast cancer in carriers did not differ from that of other BRCA2 and BRCA1 pathogenic mutations. We recommend that all suspected HBOC families from Portugal or with Portuguese ancestry are specifically tested for this rearrangement.

Earlier results [1], suggesting an autocrine tumor cell stimulation by CSF-1, are in agreement with data by Fildermann et al. [2], showing an enhanced motility and invasiveness in the CSF-1 receptor expressing BT20 breast cancer cell line upon stimulation with recombinant CSF-1. Tumor-cell secreted CSF-1 has also been shown to cause monocyte recruitment, but not cytotoxicity [3]. Down-regulation of monocyte class II antigen expression after exposure to high concentrations of CSF-1 [4] may decrease macrophage-mediated tumor cytotoxicity and favor tolerance. Raised CSF-1 serum levels may thus increase tumor metastatic behavior as well as cause immune suppression in advanced stage disease. We set out to evaluate serum CSF-1 levels in primary and metastatic breast cancer. Serum samples from one hundred and eighteen primary breast cancer patients and seventy-five patients with metastatic disease were assayed by radio-immuno-assay (RIA) for circulating colony-stimulating factor 1. Mean serum levels were significantly higher in the metastatic population (9.7 ng/ml +/- 0.8) as compared to the patients with primary tumors (4.2 +/- 0.2) (p = 0.0001). Patients with early stage tumors (T0/T1/T2) had significantly lower levels than patients with tumors of larger size (T3/T4) (p = 0.0001). Relapse and survival statistics were analyzed using Kaplan-Meier estimates. Samples from 118 primary breast cancer patients were available to study. The median follow up was 85 months (range: 1-108). An elevated CSF-1 concentration (> 6.6 ng/ml or > 550 Units/ml) was associated with a shorter disease free interval (p = 0.03). In a multivariate analysis, including T (clinical tumor size), N (clinical node status), histological grade, and hormone receptor status, CSF-1 remained significantly associated with a poorer outcome (relative risk of relapse: RR: 3.3 [1.3-8.5]), together with tumor size (RR: 2.8[1-8.2]) and clinically involved nodes (RR: 4.1[2.1-8]). These results were not modified following adjustment for type of treatment. We conclude that raised circulating CSF-1 levels may be an indicator of early metastatic relapse.

A retrospective study was performed on 109 human breast tumors stored in liquid nitrogen in order to assess the prognostic value of epidermal growth factor receptor (EGF-R) (median patient follow-up 5 years). A significant inverse relationship was observed between EGF-R and both estrogen (ER) and progesterone receptors (PR). Univariate analysis showed a trend towards a shorter metastasis-free survival both in the overall population and in node-negative patients with EGF-R positive tumors. Multivariate analysis of the overall population showed that lymph-node involvement and PR status were the only significant variables in predicting metastasis-free survival. However, in patients receiving no adjuvant treatment (hormone therapy or chemotherapy). EGF was the only significant variable in the multivariate Cox analysis. No c-erbB-1 amplification was detected in these tumors.