Hot flashes are signs of reduced risk of invasive breast cancer
Dr. Christopher Li and colleagues at the Fred Hutchinson Cancer Research Center in Settle Washington reported online on Jan 6, 2011 in Cancer Epidemiology, Biomarkers & Prevention that women who experienced hot flashes were less likely to develop breast cancer.
The authors say previous studies indicate women with menopausal symptoms like hot flashes have lower levels of estrogen, which is a female hormone that is known to promote growth of breast cancer cells, compared with women who did not have menopausal symptoms.
Because of estrogen's role in the development of breast cancer and menopausal symptoms, Li et al. proposed that there should be an association between menopause symptoms and risk of breast cancer.
Li et al. conducted a case-control study and found that postmenopausal women who ever experienced menopausal symptoms like hot flashes were 50 percent less likely to develop invasive ductal carcinoma and invasive lobular carcinoma and 30 percent less likely to develop invasive ductal lobular carcinoma, compared with those who did not experience much of any menopausal symptoms.
The associations were "independent of recency and timing of hormone therapy use, age at menopause and body mass index", the researchers reported in their publication.
Hormone therapy has been known to increase the risk of breast cancer. Late menopause is linked to increased risk of the disease and a high body mass index is linked with a high risk of breast cancer also.
Increasing intensity of menopausal symptoms was correlated with decreasing risk of all these three types of invasive breast cancers, the researchers also found.
To prevent breast cancer, which is diagnosed in more than 175,000 women in the United States each year, measures should be taken to prevent early puberty, avoiding alcohol consumption, increasing physical activity and reducing intake of calories to prevent obesity, and avoiding use of estrogen-based products like contraceptives and hormone replacement therapy intended to mitigate the menopausal symptoms like hot flashes.
David Liu, Ph.D.