Dr. Julia Lawrence, assistant professor of medicine at Louisiana State University Health Sciences Center discusses breast cancer and mammograms; October is National Breast Cancer Awareness Month and Oct. 15 is National Mammogram Day.
Q: We've all been told that early detection is key to surviving breast cancer but just when and how often should women be screened for breast cancer?
A: Screening recommendations haven't changed; it's still yearly. Any shorter interval is not any more effective. The current recommendation by the American Cancer Society is still to start at 40. But the recent debate is that there is not a mortality reduction in women between the ages of 40 and 50 (when they receive annual mammograms). We've known all along that mammograms in women between 40 and 50 are less reliable because of the density of the breast of women who are still menstruating so we know we are missing more breast cancers in women that age. [Part] of all the hormone replacement debate, too, is that hormone replacement therapy is increasing the density of the breast and decreasing the sensitivity of the mammogram to detect cancer.
Q: Recently we've heard that MRIs are more effective than mammograms in early detection. Is that true?
A: The MRI issue is really with regards to higher-risk women. The studies have primarily been done on high-risk women who have had a genetic test positive for one of the breast cancer genes and women who have had a gene found in families predisposed to certain cancers. Also included in this study were women who had a high risk for breast cancer based on their family history but didn't have a positive test for the gene, and women who had a prior diagnosis of an atypical cancer. In that select population, MRI was more effective in picking up cancers.
Q: Could MRIs replace mammograms as part of a woman's regular screening?
A: The criteria of evaluating a breast MRI is not yet standardized and not every radiologist has the expertise to review it at this time. It also [requires] specialized MRI equipment, and also it would always be more costly than a standard mammogram. The other downside to having a test that is more sensitive is that greater sensitivity also implies more false positives, meaning that more lesions are picked up that are not malignant, meaning that a woman would have to get more biopsies.
Q: What would be a reason to use both mammograms and MRIs?
A: We use MRI in women who are already diagnosed with breast cancer. A surgeon may request it to get a better idea of where it is, the vascularity, etc.
Q: What are the reasons women delay or don't get mammograms?
A: One is probably fear of finding something. That's true for a lot of people getting screenings for a lot of things. For people who don't have insurance, there is probably cost. However, in New Orleans, there is the opportunity for women to get screenings whether they have insurance or not; they just need to call LSU's Stanley S. Scott Cancer Center at 568-5151.
Q: What factors besides genetics give a woman a higher risk of developing breast cancer?
A: Other than family history-- and most people who get breast cancer don't have a family history of it -- risks are related to hormonal factors. Those hormonal factors have to do with the duration a woman is exposed to estrogen during her lifetime. That's why women who don't ever get pregnant, those who start their menstrual cycle earlier [are more prone to breast cancer]. It's a disease predominantly of age; the risk increases with age. It's probably related to the exposure to estrogen, in part, but all cancers [related to] epithelial cells increase with age.
Q: What can we do to prevent it?
A: Moderate exercise seems to decrease your risk of breast cancer. This is more convincing than low-fat diets. Diet studies are very hard to conduct, and the feeling is that's why there is not good evidence that it lowers risk for breast cancer. There are medications to decrease your risk of breast cancer. Tamoxifen has been shown, again in a population at increased risk for breast cancer, to decrease breast cancer by about 50 percent. Tamoxifen was approved for breast cancer prevention about five years ago; it's also used for breast cancer treatment.
Q: We hear a lot about the 200,000 annual cases of breast cancer in American women, but the American Society of Clinical Oncology says the disease also is on the rise in men. What's that about?
A: I don't have a reason for why there is an increase in instances. It is still very rare in men. It would not be recommended to screen men for breast cancer, but any man with a lump in a breast should go see a physician.
Q: Is there a set of risk factors for men?
A: Men actually do get just as much estrogen-sensitive breast cancer as women, but how estrogen impacts on men and why particular men are at greater risk is unknown. It's pretty understudied in men for obvious reasons.
Q: What message would you like to convey to women?
A: One important message always is that most women who have breast cancer are cured of their disease. The reason to tell women that is their fear of getting a mammogram or presenting their doctors with a lump in their breast. They need to know they should present early and not delay because most women can be cured. The whole fear of breast cancer being a killer should be dispelled. The most common presentation now is in the early stages; only 10 percent present with cancer that is metastatic, or spread. More women die of heart disease than cancer, but there is an overwhelming fear of cancer and that may adversely influence at what stage they present. If we can get the message out that early presentation saves lives, that's an important message to convey.