A recent article reports that the risk of breast cancer is higher when estrogen is started soon after menopause (less than 5 years) than when started more than 5 years after menopause. This puts women in a quandary since soon after menopause is when hot flashes and other symptoms are the worst, especially if they have just undergone surgical menopause.
How do we make sense of this and what to do about it? This is explained in detail in my book, Outliving Your Ovaries but here’s a brief explanation.
Know that estrogen does not cause NEW cancers. Most breast cancers are the end results of a decades-long evolution of increasingly abnormal premalignant cells. When women go more than 5 years without estrogen, shrinkage of some of these premalignant cells can occur. When women start estrogen soon after menopause, the estrogen can make those premalignant cells grow faster so they become easier to detect. These cancers tend to have positive estrogen receptors and are easier to treat.
It’s important to keep in mind that the increases in breast cancer are still small. For example, in statistics from the National Institutes of Health in 2006, out of 10,000 women who never took estrogen, there were 30 cases of breast cancer reported over a 5 year period. In 10,000 women who took estrogen for 5 years, there were 38 cases of breast cancer so the increased risk from estrogen was only 8 cases! Isn’t it better to consider the benefit of those 9962 women who didn’t get breast cancer and decreased their risk of heart disease, osteoporosis and dementia? Heart disease kills more women each year (352,000) than the next 16 causes of death including diabetes, ALL forms of cancer, AIDS and accidents!
A practical approach to this dilemma: if you are newly menopausal and having few symptoms, it’s reasonable to wait a year or two to start estrogen. Understand that the longer you wait after that starts the clock on degeneration of tissues that rely on estrogen, like heart, brain and bones. If you are suffering with miserable symptoms, have a mammogram 3-6 months AFTER starting estrogen to see if any previously undetectable cancers have now developed.You can stop your estrogen and you will have detected the cancer at a very early stage that is easy to treat.
Outliving Your Ovaries also outlines many proactive things you can do to lower your risk of having premalignant cells that develop into breast cancer.