Skip to main content

Blood Test Predicted Breast Cancer Risk for Postmenopausal Women

TOP - Daily

Breast cancer death and recurrence linked with elevated hormone levels

Predicting a woman’s long-term risk for developing postmenopausal breast cancer was accomplished through the use of blood hormone testing, according to data from the Nurses’ Health Study.

“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,” said Xuehong Zhang, MD, an epidemiologist at Brigham and Women’s Hospital and an instructor in medicine at Harvard Medical School in Boston, Massachusetts.

The analysis included 796 patients with postmenopausal breast cancer who had not received hormone therapy. Blood hormone tests were conducted at 2 time points: between 1989 and 1990, and between 2000 and 2002. Then, Zhang and colleagues matched 2 controls not diagnosed with breast cancer with each of the 796 patients.

The researchers discovered that women with hormone levels in the highest 25% for estradiol, testosterone, and dehydroepiandrosterone sulfate (DHEAS) had a 50% to 107% greater chance for developing breast cancer versus women in the lowest 25%. The relative risks for developing breast cancer were similar at 1 to 10 years compared with 11 to 20 years (also 16 to 20 years) following blood collection.

Furthermore, Zhang and colleagues revealed that, in general, elevated hormone levels (excluding DHEAS) tracked closely with added risk for hormone receptor–positive breast cancer.

Elevated hormone levels were also associated with recurrent or fatal cancer. “The relationship was comparable or possibly stronger for recurrent and fatal breast cancer than it was for overall breast cancer risk, although these results were based on relatively small numbers of participants,” said Zhang.

The protective effect of sex hormone-binding globulin (SHBG), which seems to negate the cancer-causing effects of certain hormones, was also confirmed by the researchers. Compared with women in the lowest 25% for SHBG levels, women in the highest 25% of SHBG levels had a 30% lower risk for breast cancer.

Zhang noted that the study had low case numbers for several cancer subgroups, including HER2-positive, triple-negative and basal-like breast cancers. More research is necessary to determine the relationship between elevated hormone levels and these important breast cancer subtypes.

Study data were presented at the 11th Annual American Association for Cancer Research International Conference on Frontiers in Cancer Prevention Research.

Source: AACR.