Emerging Breast Cancer Therapy Evidence Noted
A new study reported in the medical journal The Lancet offers more evidence for a move away from tamoxifen as the standard medication for postmenopausal women with early breast cancer whose tumor is fueled by estrogen.
Data from two trials conducted in Austria including more than 3,000 women found a 40 percent reduction in "events" - such as a new breast cancer or a spread of the tumor to another part of the body - for those who switched to a medication called an aromatase inhibitor after two years of tamoxifen therapy, compared to women who continued taking tamoxifen.
The study provides additional support for a treatment "which is not only a standard in Europe but also in the United States," says study author Dr. Raimund Jakesz, a professor of surgery at Vienna Medical University.
But whether tamoxifen should be replaced entirely by aromatase inhibitors such as anastrazole, the one used in the European trials, "is an unsolved problem," Dr. Jakesz notes.
Both tamoxifen and anastrazole prevent estrogen from spurring cancer growth - tamoxifen by blocking it from reaching the cancer cells, and anastrazole by stopping estrogen's production by body tissues other than the ovaries.
The treatment is limited to postmenopausal women because their ovaries have stopped producing estrogen.
Several studies, the largest of which included more than 6,000 women, have shown that switching from tamoxifen to an aromatase inhibitor after two years of tamoxifen therapy has a positive effect like that seen in the Austrian study, says Dr. Timothy Hobday, professor of oncology and director of the breast program at the Mayo Clinic College of Medicine.
"Making the switch is supported by the evidence, but it doesn't tell us what is the optimum thing to do with a patient starting from zero," he says. "The unanswerable question now is whether to go with an aromatase inhibitor at once or after a period of time."
A panel of experts convened by the American Society of Clinical Oncology says that aromatase inhibitor treatment "should be strongly considered," Dr. Hobday explains. "But their assessment does not come down on when to use them."
A number of factors must be considered before prescribing an aromatase inhibitor, he says. One is cost, as aromatase inhibitors are more expensive than tamoxifen.
And a major medical issue is that aromatase inhibitors "have a negative effect on bone density," he says. There has been a significant increase in fractures in women who took the medications in studies, Dr. Hobday points out.
"So what it comes down to is a case-by-case discussion - of the cost, of side effects, of an individual's breast cancer risk, of her bone density, and the characteristics of her breast cancer," he says.
An aromatase inhibitor "makes more of a difference in higher-risk patients, those with bigger tumors or cancers that have spread to the lymph nodes," he says.
Always consult your physician for more information.
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A new study in the Journal of the American Medical Association (JAMA) finds that breastfeeding infants may reduce a child's likelihood of growing up to need eyeglasses.
Researchers, in a comparison of breast-fed infants with formula-fed babies, found that breast-fed infants were slightly less likely to be nearsighted at ages 10 to 12.
"It may have to do with some constituents in breast milk, but we can't be sure," says Dr. Richard Stone, an ophthalmologist at the University of Pennsylvania and a co-author of the research letter.
Dr. Stone suggests that a substance in breast milk, docosahexaenoic acid, or DHA, may underlie the decreased risk of myopia.
DHA is a fatty acid crucial for the growth and functional brain development in infants and it is also required for maintenance of normal brain functioning in adults.
It is also important, the study authors note, for the development of photoreceptor cells in the retina, which play a major role in whether children become nearsighted.
The retina lines the inner eyeball and is connected by the optic nerve to the brain.
The eye's lens focuses light on the retina, which then converts this light into signals sent to the brain.
In nearsightedness, the eyeball is too long and light rays focus in front of the retina, rather than on it, causing the person to be able to see objects up close but not at a distance.
In developed countries, nearsightedness is the leading cause of visual impairment, the authors note, and in the US more than 30 million adults are nearsighted.
The prevalence of myopia has been increasing among urban Asian children, Dr. Stone adds.
While the study is believed to be the first to observe an association between breastfeeding and myopia, other studies have found that breastfeeding is good for the development of children's eyes and is associated with better school performance by children.
Several of these studies have been conducted by scientists at the Retina Foundation of the Southwest in Dallas, Texas.
Dennis Hoffman, director of the visual biochemistry lab at the foundation, says the new study findings are consistent with those done by his group.
"We've shown that breast-fed infants have improved visual maturation at one and a half years, compared to those fed formula," he adds.
Dr. Stone and his colleagues, led by Dr. Yap-Seng Chong of the National University of Singapore, evaluated 797 Singapore children at ages 10 to 12, including 418 who had been exclusively breast-fed and 379 who had not been.
While 62 percent of the breast-fed children had myopia, or nearsightedness, 69 percent of those not breast-fed did. "It's really a modest effect," Dr. Stone explains.
Even after the researchers controlled for factors such as the parents' nearsightedness, maternal age at delivery, and birth weight, the association still held.
Always consult your physician for more information.
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