 | What Your Doctor Is Reading | | |
Update From the Medical Journals: April 2007
April 30, 2007  By Mary Pickett, M.D.
Harvard Medical School What's the latest news in the medical journals this month? Find out what your doctor is reading. MRI Now Recommended for Women With High Breast-Cancer Risk In the March/April 2007 issue of CA: A Cancer Journal for Clinicians, the American Cancer Society (ACS) recommended that women with a high risk for breast cancer should get a yearly magnetic resonance imaging (MRI) scan of the breast, in addition to a yearly mammogram. According to the ACS, up to 1.4 million women in the United States should be getting annual breast MRI scans. The MRI scan is more sensitive than a mammogram, so it finds some cancers that a mammogram misses. An MRI scan costs about ten times more than a mammogram, so it's not practical to advise that all women have the test. That's why this new recommendation proposes breast MRI only for women who have a high risk of breast cancer due to: - A BRCA 1 or BRCA 2 gene mutation (some women who have breast cancer in the family have gone through genetic testing)
- A mother or sister with either of the BRCA gene mutations or another genetic mutation that is known to raise your breast cancer risk
- Previous intensive radiation to the chest, such as treatment for lymphoma
- A lifetime risk for breast cancer greater than 20%
Prior to this recommendation, high-risk women followed the same screening guidelines as all adult women or began screening at a younger age if they had a very young relative with cancer. Tools to estimate a woman's lifetime breast-cancer risk will be used more widely now by doctors since the result could change decisions. One example of a breast cancer prediction tool is provided by the National Cancer Institute (NCI). It estimates a woman's chance of getting invasive breast cancer based on, for example, age, previous history of breast cancer, family history of breast cancer and age when your menstrual periods began. Back to top Mammograms: Women Ages 40 to 49 Have a Choice To Make For several years, the American Cancer Society (ACS) and the NCI have recommended that women ages 40 to 49 have a mammogram every one to two years, just as they advise women 50 and older to do. But the American College of Physicians (ACP) published a slightly different guideline in the April 3 issue of the Annals of Internal Medicine. It suggests that breast cancer screening be optional for women ages 40 to 49, and advises women in their 40's to talk to their doctors about the pros and cons of screening, then decide for themselves if they do or don't want to be screened. When you consider the facts, you can see why the decision to have mammograms in your 40's is not an obvious one. Mammograms find some cancers in women who are in their 40's. However, the information comes at a price for women as a whole. By one estimate, in order to save six women who would die of cancer without screening, about 10,000 women in their 40's need to get mammograms every one to two years. Because mammograms are more technically difficult to review in women who are young, almost half of women under age 50 who have mammograms are called back to have repeat films or biopsies due to suspicious findings. Obviously, this can lead to worry, inconvenience and, in some cases, unnecessary risk from biopsy procedures. Back to top Medicines Are as Good as Angioplasty for Chest Pain — Except in an Emergency A large study published in the April 12 issue of the New England Journal of Medicine compared treatment with and without angioplasty for heart patients who had recurring episodes of chest pain. The study found the benefits of each to be equal. The results were similar in terms of symptom relief, hospitalization for chest pain symptoms and heart attacks over a period of five years. Researchers studied 2,287 patients from the United States and Canada who had blockages shown on heart catheterization studies. Most of the patients had an average of ten episodes of chest pain per week and 40% had had a previous heart attack. Following standard medical practice, the patients were given medicines to increase blood flow, limit the oxygen demand by the heart and prevent a heart attack. The patients in the study were all encouraged to eat a good diet, exercise and avoid smoking. Half of the patients were assigned to have their arteries widened by an angioplasty, with or without a stent. About one out of five patients died or had a heart attack during the next 4 ½ years, whether they had angioplasty or not. About three out of four people had no chest pain when they were surveyed at three years, and again at five years. Pain-free rates were not very different from one group to the other. About one-third of the people assigned to the "drugs only" group could not get relief from their medicines, and they eventually chose to have an angioplasty or bypass surgery to relieve their symptoms. This study did not question the benefit of angioplasty for chest pain emergencies, such as chest pain that has abruptly become more frequent or chest pain from a heart attack. Angioplasty should still be the first choice treatment in those situations. For exercise-induced chest pain that has a stable pattern, treatment with medications is the most sensible way to begin. For most patients, medication is less expensive and no less effective than angioplasty. Back to top More News in Brief - Antidepressants Add Little to Treatment for Bipolar Disorder. The first choice of drugs for bipolar disorder (also known as manic depressive disorder) are mood-stabilizing drugs such as lithium, valproic acid, or carbamazepine. These medicines are different from traditional antidepressants. A study in the March 28 issue of the New England Journal of Medicine looked at the benefits of adding antidepressant medications to treat patients with bipolar disorder who were already taking mood stabilizing medicines. The study included 366 patients at 22 sites in the United States. In addition to their mood stabilizing medicine, they were randomly assigned to receive an antidepressant — either paroxetine (Paxil) or bupropion (Wellbutrin) — or a placebo pill. The results showed that the same proportion of patients recovered from depression symptoms over the 6-month study period with or without the addition of an antidepressant. In addition, about 10% of patients in both groups developed symptoms of mania. Doctors had concerns previously that antidepressants might trigger mania, but this finding suggests that this is rarely or never the case.
- Computer Review of Mammograms Does Not Improve Their Accuracy. A study published in the April 5 issue of the New England Journal of Medicine revealed disappointing results about the benefits of using a Computer Aided Detection (CAD) tool to read mammograms. CAD points out suspicious areas on a mammogram that need a closer look by a radiologist. Researchers compared the accuracy of mammograms with and without CAD using 400,000 mammograms that were done between 1998 and 2002 at 43 facilities in three states. There were so few additional cancers found that experts now think that the technology as it is now is not adding anything truly beneficial to mammogram reading. For every cancer that the CAD software "marked," the computer also marked roughly 2,000 places where there was no cancer, requiring closer review. This increased the expense of screening by 18%. The study also found that CAD had a higher rate of false positives than mammogram alone. The researchers estimated that for every cancer that would have been missed without the computer reading, there were 156 women who were called back for extra tests and about 14 women who had unnecessary biopsies. If the software is improved over time, it might eventually become worth using. (One note: CAD is not the same thing as "digital mammography," which is a clearer picture from the X-ray than standard X-ray film. Unlike CAD, digital mammography has a proven benefit as a breast cancer screening technology.)
- Stem-Cell Transplant Shows Promise for Type 1 Diabetes. In the April 11 issue of the Journal of the American Medical Association (JAMA), doctors shared preliminary results of using stem cell transplantation to treat (and possibly cure) 15 young people who were in the beginning stages of type 1 diabetes. According to the promising results most of the patients have been able to discontinue insulin, and few complications have been seen so far. It is not known whether the benefits will be permanent. The idea behind the treatment is first to eliminate the activity of the immune system with toxic immune suppression drugs, since an attack by the immune system on the pancreas is what causes type 1 diabetes. Then the stem cell transplant provides a new immune system. There is a large infection risk until the immune system has restored itself, but this extreme treatment may be a way to abort destruction of the pancreas.
- Zelnorm (Tegaserod) is Withdrawn from the Market. Tegaserod is a drug that has been used to treat constipation in people with irritable bowel syndrome. Unfortunately, the drug was linked to higher rates of heart attack and "unstable" angina, a warning sign for heart attack, and stroke. The drug was taken off the market by request of the U. S. Food and Drug Administration (FDA). The heart and stroke events occurred in only a very small fraction of users, but they occurred at roughly twice the expected rate.
- Drug-Resistance Prompts Change in Recommendations for Gonorrhea Treatment. In the April 13 issue of the Morbidity and Mortality Weekly Report (MMWR), the Centers for Disease Control and Prevention (CDC) advised doctors against using the antibiotic ciprofloxacin, which has long been the treatment of choice for gonorrhea, a sexually transmitted infection. Nearly 7% of gonorrhea in the United States is now resistant to ciprofloxacin and other antibiotics in its drug group. Doctors will instead need to use a cephalosporin antibiotic, such as cefixime or ceftriaxone. More than 700,000 people in the United States are infected with gonorrhea each year.
Back to top Mary Pickett, M.D. is a lecturer for Harvard Medical School and an assistant professor of medicine at Oregon Health & Science University. At OHSU, she is a director of student programs and she oversees teaching of students and medical residents. She practices general internal medicine in Portland, Ore.
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