BRCA1, BRCA2 and TP53 mutations in very early-onset breast cancer with associated risks to relatives.

Pathological mutations in BRCA1, BRCA2 and TP53 are associated with an increased risk of breast cancer. This study evaluated mutation frequency of these genes in early-onset breast cancer patients, and correlated this with family history and determined relative risks to family members. Patients with breast adenocarcinoma diagnosed 30 years were ascertained between 1980 and 1997.

Prediction of pathogenic mutations in patients with early-onset breast cancer by family history.

We aimed to assess frequency and penetrance of BRCA1, BRCA2,and TP53 mutations in women diagnosed with breast cancer aged 30 years or younger, and then correlate this frequency with family history. 17 of 36 familial cases had a BRCA1, BRCA2, or TP53 mutation, compared with three of 63 non-familial cases. The calculated population frequency of TP53 mutations was one in 5000, substantially greater than previous estimates.