To characterize the biological features of breast cancer associated with germ-line mutations in BRCA1 and BRCA2, invasive tumors were studied from 58 Jewish women ascertained through studies of early-onset breast cancer.
In most Western populations, 5-10% of all breast cancer cases can be attributed to major genetic factors such as predisposing mutations in BRCA1 and BRCA2, with early-onset cases generally considered as an indicator of genetic susceptibility.
Germline mutations in the BRCA1 and BRCA2 genes in patients with early-onset breast cancer have not been clearly identified within the Algerian population.
Early age at diagnosis of breast cancer, ovarian cancer, bilateral breast cancer were associated with BRCA1, whereas male breast cancer and four or more breast cancer cases in the family were associated with BRCA2.
Much has been learned during the past decade about the genetic epidemiology of breast cancer, the ethnic distribution and clinical consequences of BRCA1 and BRCA2 mutations, and the central role of DNA repair in breast cancer susceptibility.
The term-pregnancies number was a significant risk-reducing factor for breast cancers in BRCA1 mutation carriers (HR per pregnancy, 0.640; 95% CI, 0.508-0.806; P < .001), for breast cancers in BRCA2 mutation carriers (HR per pregnancy, 0.534; 95% CI, 0.419-0.681; P < .001), and for ovarian cancers for BRCA1 mutation carriers (HR per pregnancy, 0.625; 95% CI, 0.474-0.824; P = .001).
Genetic defects in breast cancer (BC) susceptibility genes, most importantly BRCA1 and BRCA2, account for ~40% of hereditary BC and ovarian cancer (OC).
Of 1054 BRCA-negative, high-risk Hispanic women, 4.5% carried a PV in a cancer susceptibility gene, increasing understanding of hereditary BC in this population.
The per-allele hazard ratio (HR) for breast cancer was 1.02 (95% CI 0.93-1.12, P = 0.66) for BRCA1 mutation carriers and 0.92 (95% CI 0.82-1.04, P = 0.17) for BRCA2 mutation carriers.
Five cases carried the BRCA1 C4446T mutation and two cases carried the BRCA28765delAG mutation which are the most common mutations that have been described in French Canadian breast cancer and breast ovarian cancer families.
Surveillance of the ovaries is recommended in BRCA1 and BRCA2-mutation carriers, in members from breast/ovarian cancer families and in some centres in 'breast cancer only' families with an early onset of breast cancer.
In Austria, the majority of healthy women with a BRCA1 or BRCA2 mutation opt for preventive oophorectomy and MRI screening to manage their breast cancer risk; few have preventive mastectomy or take tamoxifen.
In this report we present the results of mutational analysis of the BRCA2 coding sequences in 105 high-risk individuals affected with breast cancer and/or ovarian cancer and previously found to be negative for mutations of the BRCA1 coding sequence in our laboratory.
For the first time, we used HRM and MLPA to identify BRCA1 and BRCA2 mutations in Algerian patients with a personal and family history suggestive of genetic predisposition to breast cancer.
Moreover, carriers of mutations in the breast cancer predisposition gene, BRCA2, have an increased risk of melanoma while carriers of mutations in the melanoma susceptibility gene, CDKN2A, exhibit a higher than expected risk of breast cancer.
Our data show that CPM markedly reduces the risk of contralateral breast cancer among BRCA1 or BRCA2 mutation carriers with a history of breast cancer.
We have previously reported linkage to the BRCA2 region in an Icelandic male breast cancer family and subsequently found a strong indication of linkage to BRCA2 and the same BRCA2 haplotype in breast cancer cases from 15 additional families, indicating a common origin.
This study assessed the pathological mutation detection rates for BRCA1, BRCA2 and the CHEK2c.1100 delC mutation in 2022 women with breast cancer, including 100 with breast/ovary double primary and 255 with bilateral breast cancer.