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A large number of cancer predisposing BRCA1/BRCA2 mutations have been reported, with a wide variety among populations. In some restricted groups, specific germline mutations in these tumor suppressor genes have been found with high predominance, due to a founder effect. We focused our review on the Italian founder mutations. The first Italian BRCA1 founder mutation, 5083del19, was found in Calabria: the presence of common allele in all carriers of this mutation (also in families with Calabrian origin living in other parts of Italy) confirmed its founder effect. The same BRCA1 mutation was identified in the Sicilian population, but only the haplotype analysis can reveal the common ancestor of these groups. Another BRCA1 founder mutation, 4843delC, was found in Sicily. Four distinct BRCA1 mutations are attributable to families original from Tuscany: 3348delAG, 3285delA, 1499insA and 5183delTGT; the latter has been shown to be a founder mutation from North-Eastern Italy. The first BRCA2 mutation was identified in Sardinia, 8765delAG, a mutation already described as a founder mutation in Jewish-Yemenite families and also in French-Canadian population but with independent origins of carriers in these three populations. BRCA2 3951del3 and BRCA1 917delTT have been described as founder mutations in Middle Sardinia and in South and Middle Sardinia, respectively. Studies regarding prevalence and penetrance of founder mutations can allow to quantify the degree of homogeneity within a population and can surely help the geneticist and oncologist to simplify their choices in the genetic testing on high-risk families, on the basis of their ethnical origin.

The aim of the study was to identify p53 gene mutations by FAMA (fluorescence-assisted mismatch analysis) in colorectal cancers.

Recently, chemoprevention trials have demonstrated the efficacy of preventive medical treatment (PMT) in reducing breast cancer (BC) detection rates in at-risk affected and unaffected women selected according to clinical and/or familial risk criteria, particularly with the use of tamoxifen (TAM). Major concerns limiting the routine use of TAM are the questionable benefit/risk ratio and poor patient compliance, which justify the studies undertaken to determine the efficacy of aromatase inhibitors (AIs) with respect to TAM. Issues such as therapy duration, impact on survival, incidence of side-effects and which subsets benefit most from treatment, still remain unsolved. Therefore, only ER+ BC patients are routinely subjected to PMT, independently of their BRCA1/2 status, using adjuvant hormonal therapy. More attention must be focused towards BRCA1/2 carriers as they are probably the women at highest risk of developing BC, in which available data remain controversial and in which hormone-therapy might be important. Hence, at-risk women (affected patients or unaffected women) should be carefully evaluated for inclusion into highly selected preventive clinical trials aimed at evaluating PMT independently of, or according to, BC predisposition status (unknown, positive or negative BRCA1/BRCA2 status) and with respect to menopausal status. BC patients, harboring a BRCA1/2 predisposition, may represent the best subset for extended adjuvant treatment, useful as PMT, simultaneously. Only the evolving differentiation of categories of at-risk women will allow physicians to discriminate PMT in a highly selective manner.

Familial breast cancer, whether associated or not with particular other breast cancer features (male, early onset, bilateral breast cancer), determines a wide and variable risk of developing breast cancer in the ‘unpatients’ (unaffected individuals) of these families, particularly in those harboring a genetic predisposition. The antiestrogen tamoxifen has been proposed in different trials to prevent breast cancer in women at risk. The NSABP-P1 study demonstrated that tamoxifen drastically reduced (by ∼50%) the incidence of breast cancer in women at risk selected according to the Gail score. The preventive effect was particularly consistent in postmenopausal women and in those showing familial breast cancer (three or more affected patients). BRCA1/BRCA2(BRCA1/2) gene analysis in women accrued in the NSABP-P1 trial who developed breast cancer showed that tamoxifen chemoprevention reduced breast cancer incidence in BRCA2carriers. Different chemoprevention trials are ongoing to compare different selective estrogen receptor modulators and aromatase inhibitors with tamoxifen. The Italian Consortium of Hereditary Breast Ovarian Cancer recently developed the Aromasin® Prevention Study, a multicenter, double-blind, randomized, placebo-controlled phase III study evaluating the effect of the aromatase inhibitor exemestane for chemoprevention in postmenopausal women carriers of BRCA1/2genetic predisposition. Women who are postmenopausal unaffected carriers of BRCA1/2mutations will be selected by participating institutions and randomly assigned to receive either oral exemestane or oral placebo every day for 3 years in order to reduce the incidence of breast cancer. Genetic counseling and the detection of predisposing BRCA1/2mutations are mandatory before accrual into the study. Signed informed consents for the performing of BRCA1and BRCA2genetic analysis and for enrollment into the study are required. Eligible women will be followed thereafter in order to evaluate the efficacy of exemestane in reducing the incidental rate of breast cancer in unaffected postmenopausal carriers of BRCA1/2mutations.