Td. Shafman et al., Prevalence of germline truncating mutations in ATM in women with a second breast cancer after radiation therapy for a contralateral tumor, GENE CHROM, 27(2), 2000, pp. 124-129
Patients treated with conservative surgery and radiation therapy for early-
stage breast cancer develop a contralateral breast cancer at a rate of appr
oximately 0.75% per year. Ataxia-telangiectasia (AT) is an autosomal recess
ive disease that is characterized by increased sensitivity to ionizing radi
ation (IR) and cancer susceptibility. Epidemiologic studies have suggested
that AT carriers, who comprise 1% of the population, may be at an increased
risk for developing breast cancer, particularly after exposure to IR. To t
est this hypothesis, we analyzed blood samples from 57 patients who develop
ed a contralateral breast cancer at least 6 months after completion of radi
ation therapy for an initial breast tumor. A cDNA-based truncation assay in
yeast: was used to test for heterozygous mutations in the ATM gene, which
is responsible for AT. No mutations were detected. Our findings fail to sup
port the hypothesis that AT carriers account for a significant fraction of
breast cancer cases arising in women after exposure to radiation. Genes Chr
omosomes Cancer 27:124-129, 2000. (C) 2000 Wiley-Liss, Inc.