There are many things to worry about as we age. One that seems to increasingly creep up as we reach menopause is the worry about cancer. Two new studies that were reported at the 11th Annual American Association for Cancer International Conference on Frontiers in Cancer Prevention Research provide some interesting fodder for women who are middle-age and older to consider.
Blood Hormone Levels and Cancer
A new study found that tests of blood hormone levels can predict a woman’s risk for developing postmenopausal breast cancer for up to two decades. The study out of Harvard Medical School involved 796 women who took part in the Nurses’ Health Study who had postmenopausal breast cancer and who hadn’t used hormone therapy. The researchers looked at data from blood hormone tests that were conducted twice during the study – between 1989-1990 and then again between 2000-2002. The researchers then matched each woman with two controls who weren’t diagnosed with breast cancer.
The researchers found that women who had hormone levels that were in the highest 25th percentile for estradiol, testosterone and dehydroepiandrosterone sulfate (DHEAS) had between a 50 percent to 107 percent greater chance of developing breast cancer than women who were in the lowest 25th percentile for these hormones. They also found that the risk for developing breast cancer remained the same between years 1-10 and years 11-20 after blood was collected.
The analysis also found that elevated levels of estradiol increased a woman’s risk for being diagnosed with hormone receptor-positive breast cancer; additionally, increased hormone levels – with the exception of DHEAS – also were linked to increased risk for HR-positive breast cancer. Elevated hormone levels also were linked to aggressive breast cancer, which was defined by the researchers as recurrent or fatal cancer. The researchers also found that sex hormone-binding globulin (SHBG) had a protective effect, negating the cancer-causing effects of specific hormones. They found that women who were in the 25th highest percentile of SHBG levels actually had a 30-percent lower risk for breast cancer than the women who were in the lowest 25th percentile for SHBG levels.
“We, and others, are now evaluating if the addition of hormone levels to current risk prediction models can substantially improve our ability to identify high-risk women who would benefit from enhanced screening or chemoprevention,” said Dr. Xuehong Zhang, an epidemiologist at Brigham and Women’s Hospital and an instructor in medicine at Harvard Medical School in Boston, Mass. “If so, the current data suggest that hormone levels would not need to be measured in the clinic more than once every 10, or possibly 20, years.”
Older Women and Cancer
Another study out of the University of Minnesota found that maintaining a healthy body weight, staying physically active and eating a healthy diet increased the rate of survival in older women who have been diagnosed with cancer. The researchers were specifically looking at the women’s adherence to the guidelines laid out by the 2007 World Cancer Researcher Fund and American Institute for Cancer Research.