Prediction of contralateral breast cancer: external validation of risk calculators in 20 international cohorts.

Background: Three tools are currently available to predict the risk of contralateral breast cancer (CBC). We aimed to compare the performance of the Manchester formula, CBCrisk, and PredictCBC in patients with invasive breast cancer (BC).

Methods: We analyzed data of 132,756 patients (4682 CBC) from 20 international studies with a median follow-up of 8.

CHEK2*1100delC homozygosity in the Netherlands--prevalence and risk of breast and lung cancer.

The 1100delC mutation in the CHEK2 gene has a carrier frequency of up to 1.5% in individuals from North-West Europe. Women heterozygous for 1100delC have an increased breast cancer risk (odds ratio 2.

Clinical correlates of low-risk variants in FGFR2, TNRC9, MAP3K1, LSP1 and 8q24 in a Dutch cohort of incident breast cancer cases.

Introduction: Seven SNPs in five genomic loci were recently found to confer a mildly increased risk of breast cancer.

Methods: We have investigated the correlations between disease characteristics and the patient genotypes of these SNPs in an unselected prospective cohort of 1,267 consecutive patients with primary breast cancer.

Results: Heterozygote carriers and minor allele homozygote carriers for SNP rs889312 in the MAP3K1 gene were less likely to be lymph node positive at breast cancer diagnosis (P = 0.