Departments
Health Matters
|
Week of 17 April 1998 |
Vol. I, No. 28 |
Health Matters
Annual mammograms: A necessary precaution
With all the conflicting news on mammograms recently, what should I believe? I am approaching 40 and am not sure how often I should be tested.
A mammogram is a special kind of X ray that can pick up most, but not all, breast cancers before they can be felt as lumps. Consequently, it has been an invaluable tool in detecting breast cancer in older women (ages 40 to 79) and in saving many thousands of lives. While doctors agree that women between the ages of 50 and 70 should have annual mammograms, there is ongoing controversy over whether women between 40 and 50 should also do so.
Karen Freund, M.D., chief of the Women's Health Unit at Boston Medical Center and associate professor of medicine at the Boston University School of Medicine, says that despite the controversy, she believes the benefits of annual mammography for women in their 40s outweigh the risks. "I think that the data are fairly convincing. It's not as convincing as the data on the benefits for older women, but I recommend mammography to all my patients between 40 and 50."
Freund stresses that mammograms are not harmful at any age. However, there are certain risks associated in particular with women between 40 and 50. One important risk is a false negative, where the breast cancer is not revealed by the mammogram. "Up to one fourth of all invasive breast cancers are not detected by mammography" in this age group, a National Institutes of Health bulletin on breast cancer notes. "The test can't be trusted blindly," says Freund, and adds that women should regularly conduct self-exams on a monthly basis. "Mammograms cannot give completely accurate diagnoses all the time. If a woman finds a lump in her breast, even though she had a recent negative mammogram, it is vital that she have her physician examine her." Another risk is a false positive, where the mammogram reveals a lump that is benign, or noncancerous. Noncancerous lumps are more common than malignant lumps and are found most often in women under, rather than over, 50. While further tests can determine if a lump is cancerous or noncancerous, false positives can produce emotional trauma.
One of the most important risk factors in breast cancer is having a first-degree relative (a mother or sister) with breast cancer. According to Freund, these women should start having annual mammograms five years before the age their relative was when first diagnosed; i.e., if a woman's older sister was diagnosed with breast cancer at 43, then the younger sister should have her first mammogram at age 38.
If a mammogram does show a lump, there are other tests that can be performed to determine whether or not it is cancerous. In some cases, an ultrasound (a noninvasive procedure where soundwaves bounced off the interior of the body create an image of the lump) can be used to help make this determination. Another option is a fine-needle aspiration biopsy, where a small needle is inserted into the breast and a few cells are extracted from the lump to determine whether or not the lump is cancerous. In some cases, a biopsy (minor surgery in which the lump is removed for analysis) is needed. Little risk is involved, and the side effects are usually no worse than minor temporary discomfort and some scar tissue.
Freund emphasizes that the controversy over annual mammograms only pertains to women under 50, and that for women over 50 there is no question that annual mammography is essential. She doubts that the controversy will be definitively solved in the near future, since the studies that formed the current argument were massive and not easily repeated. "This is pretty much the data we're going to have to live with for awhile," she says.
Women interested in obtaining further information on mammography and breast cancer can access these Web sites: http://www.health net.com/brdet.htm (Breast Cancer Detection) and http://trfn.clpgh.org/ bcis/(Breast Cancer Information Service).
"Health Matters" is written in cooperation with staff members of Boston Medical Center. For more information about mammograms or other health matters, call 617-638-6767.