AACR: Single Hormone Test IDs Long-Term Breast Cancer Risk
(HealthDay News) – For postmenopausal women, a single blood test for sex hormone levels can predict the risk of hormone receptor-positive breast cancer for as long as 20 years, according to a study presented at the American Association for Cancer Research's International Conference on Frontiers in Cancer Prevention Research, held from Oct. 16 to 19 in Anaheim, Calif.
Xuehong Zhang, M.D., from Brigham and Women's Hospital and Harvard Medical School in Boston, and colleagues examined how long a single blood hormone measure can predict subsequent risk of breast cancer and whether the association varies by tumor hormone receptor status. Blood samples were collected in 1989 to 1990 and in 2000 to 2002, and 796 cases were diagnosed among eligible postmenopausal women, who were not using postmenopausal hormones, through June 2010. Cases were matched to 1,583 controls.
The researchers found that women in the top quartile for levels of estradiol, free estradiol, testosterone, free testosterone, and dehydroepiandrosterone sulfate (DHEAS) had a 50 to 107 percent increased risk of breast cancer, compared with those in the lowest quartile. The risk of breast cancer was lower for those in the highest versus the lowest quartile of levels for sex hormone binding globulin. Similar relative risks were observed for cases diagnosed one to 10 years, 11 to 20 years, and 16 to 20 years after blood collection. With the exception of DHEAS, the associations varied significantly by hormone receptor status of the tumor, with increased hormone levels generally associated with increased risk for hormone receptor-positive breast cancer.
"We found that a single hormone level was associated with breast cancer risk for at least 16 to 20 years among postmenopausal women not using postmenopausal hormones," Zhang said in a statement.