New York: Although fewer and fewer women have died of breast cancer each year over the past two decades, a new study suggests that improvements in survival have been slowest for the oldest women with the disease.
Women 75 and older who are diagnosed with breast cancer tend to get less-aggressive treatment than younger women, researchers noted in their report, published in the Journal of Clinical Oncology. That`s both because the disease can be slower-growing in that group, and because a shorter life expectancy means some might not live long enough for the treatment to make a difference.
The older women also may not tolerate powerful medications as well as younger ones.
"You don`t want to treat older women so aggressively that you actually cause more problems from the treatment than from the disease," said Dr. Benjamin Smith, of the University of Texas MD Anderson Cancer Center in Houston, who worked on the study.
But, he added, "When they are treated with chemotherapy, it probably doesn`t quite do the same as it might in younger women if you can`t give the chemotherapy in quite the same doses and at quite the same intensity."
Guidelines from the U.S. Preventive Services Task Force also stop calling for regular breast cancer screening in all women older than 74 -- after that, the decision should be between a woman and her doctor.
Less screening could contribute to older women getting diagnosed when their cancer is farther along, researchers said -- but it also avoids catching (and treating) small cancers that wouldn`t turn into anything.
Smith and his colleagues used two nationwide databases to track the number of women dying from breast cancer every year in the U.S. overall, as well as the proportion of women with a new diagnosis who die from the disease.
Both numbers, they found, have been on the decline since 1990. But the drop hasn`t been equal in all women.
In 1990, 158 out of every 100,000 women age 75 and older died from breast cancer. That fell to 129 in 2007.
Among 20-to-49-year-olds, death rates almost halved -- from 14 to eight out of 100,000 women over the same time period.
That works out to a one-percent yearly drop in deaths in women 75 and older, compared to a 2.5-percent drop for those in their 20s, 30s and 40s.
Smith said that more research is needed to figure out the best way to treat cancer in older women -- as doctors generally have to extrapolate from studies of women in their 60s and younger.
For now, he added, women should be involved in decisions about their own treatment and share concerns about treatment side effects and their general health.
"For older women with breast cancer, I think it`s really important to try to seek out high-quality care for your cancer, and try to have good conversations with your doctors to discuss what`s the most you could do (and) what`s the least you could do."
Dr. Mara Schonberg, who has studied breast cancer in older women at Harvard Medical School in Boston, agreed that doctors should take the whole health picture into account when treating their older patients.
"We`re not great at considering patients` life expectancy in treatment decisions," she told Reuters Health. "There are many women with less than five years` life expectancy getting treatments from which they are unlikely to benefit, and there are probably women with adequate life expectancy not getting treatment."
The new study "does suggest there are probably some women who would benefit from more aggressive treatment" -- but not all, said Schonberg, who wasn`t involved in the new research.
Still, Smith said, the message is mostly a positive one. "For the most part, this paper is just this amazing story of the wonderful successes that we`ve had in lowering the burden of breast cancer in the United States. I think that`s not to be lost."