Breast cancer is the most common cancer in women. Some women have a family history of breast cancer. They are at especially increased risk. Unfortunately, most women who develop breast cancer do not have a family history. Therefore, all women must be considered to be at risk for breast cancer.
Some breast cancers are stimulated by estrogen. Women with a family history of breast cancer should generally avoid taking estrogen. Exposure to estrogen beyond age 70 is associated with increased breast cancer risk.
Hormone Replacement Therapy does carry an increased risk of breast cancer, especially in women over 70. Most physicians advise stopping HRT before age 70 for this reason.
There are 2 estrogen-like medications which actually decrease breast cancer risk. They do this by competing with a woman’s natural estrogen for the estrogen receptors in breast tissue. Raloxifene (Evista) and Tamoxifen both can occupy the estrogen receptors in breast tissue and block their activation by the woman’s own estrogen. This protects the woman from developing estrogen dependent breast cancer by about 70%.
Tamoxifen is approved for both prevention and treatment of breast cancer. Tamoxifen does not harm bone. The more aggressive modern breast cancer treatments (Aromatase Inhibiters) do harm bone. Unfortunately, Tamoxifen has not been shown to preserve bone either.
Evista preserves bone and decreases Fracture Risk. More about preventing breast cancer and decreasing fracture risk next time.
Jay Ginther, MD
Many genetic causes of excessive bleeding and excessive clotting run in families. Fortunately they are uncommon. Members of families with bleeding or clotting abnormalities need to be careful of medications which can alter clotting abilities.
Aspirin and Non-Steroidal Anti-Inflamatory Drugs (NSAIDs) are the most common pharmaceuticals increasing bleeding. St John’s Wort and Ginseng are among the “natural supplements” which can increase bleeding.
Estrogen can increase the risk of blood clots. This is especially true during pregnancy, when estrogen levels are their highest. The lower levels of estrogen found naturally in pre-menopausal women, and in Hormone Replacement Therapy patients, very slightly increase the risk of clots.
Modern Hormone Replacement Therapy (HRT) is safe in most women through their 60′s. 20 years ago, when Progesterone was included in the formulation, HRT was associated with heart problems. Estrogen alone in modern HRT avoids this issue, at least until age 70. Recent studies have shown that modern HRT actually decreases heart disease deaths in women in their 50′s.
Modern HRT is most commonly used to treat menopausal symptoms. However, human estrogen is what naturally preserves bone in a pre-menopausal woman. Restoring human estrogen will also preserve bone in a post-menopausal women. You can postpone Osteoclasts Gone Wild eating away your bones!
A delicate balance between bone formation and bone resorption is needed for Healthy Bone. This balance is naturally present until menopause in a woman or “Low T” in a man. The main players are OsteoBlasts, OsteoClasts, and OsteoCytes.
OsteoBlasts are cells that build bone by producing bone matrix (Anabolic). OsteoClasts are cells that resorb or take away bone (Resorptive). Both live on the surface of bone. OsteoCytes live inside bone and control the balance of formation and resorption through the hormone Osteoprotegrin (OPG). OPG supresses the number and activity of OsteoClasts.
Estradiol is the hormone that tells the OsteoCytes to make enough OPG to keep the Osteoclasts under control. Women make Estradiol from Estrogen. Men make Estradiol from Testosterone. Women after menopause (about age 50) and men after about age 70 no longer make enough Estradiol to produce enough OPG. Then it is Osteoclasts Gone Wild.
Modern Hormone Replacement Therapy (HRT) is an obvious possibility in a woman. Estrogen is back on board. Prolia (Denosumab in osteoporosis dose), and Evista (Raloxifene), are two novel osteoporosis medications designed to bring unruly OsteoClasts under control. They both mimic the natural process, but in different ways. We will address each in coming posts.
Take Back Control with whatever medication works best for you.
Jay Ginther, MD