SAN FRANCISCO (EGMN) - White women of European descent who have breast cancer and a CHEK2*1100delC mutation are 40% more likely to die of breast cancer or from any cause, and 170% more likely to develop a second breast cancer within 10 years, compared with those who don't have the mutation, an analysis of data on 11,873 patients found.The increased mortality and recurrence risks in women with breast cancer and a heterozygous CHEK2*1100delC mutation don't appear until more than 5 years after breast...