To be safe, Jennifer Mukai all but eliminated soy from her diet after being told she had breast cancer in May 2009.
Being of Japanese descent and also health conscious, the Seattle interior designer says she was eating a lot of soy in various forms before her diagnosis.
“I drank about three-quarters of a cup of soy milk in my coffee twice a day and ate tofu and edamame [soy beans] pretty regularly,” the 44-year-old tells WebMD. “I was also probably getting quite a bit of soy in the meat-substitute...
About 75% of all breast cancers are “ER positive.” They grow in response to the hormone estrogen. About 65% of these are also “PR positive.” They grow in response to another hormone, progesterone.
If your breast cancer’s cells have a significant number of receptors for either estrogen or progesterone, your cancer is considered hormone-receptor positive and likely to respond to endocrine therapies.
Breast cancer tumors that are ER/PR-positive are 60% likely to respond to endocrine therapy. Tumors that are ER/PR negative are only 5% to 10% likely to respond to endocrine therapy.
Endocrine therapies for breast cancer are treatments usually taken after surgery, chemotherapy, and/or radiation are finished. They are designed to help prevent recurrence of the disease by blocking the effects of estrogen. They do this in one of several ways.
The drug tamoxifen, taken by some women for up to 10 years after initial treatment for breastcancer, helps prevent recurrence by blocking the estrogen receptors on breast cancer cells and preventing estrogen from binding to them.
A class of drugs called aromatase inhibitors actually stops estrogen production in post-menopausal women. These drugs cannot be taken by women who have not yet gone through menopause.
HER2-Positive Breast Cancer
In about 20% to 25% of breast cancers, the cancer cells make too much of a protein known as HER2. These breast cancers tend to be much more aggressive and fast-growing.