Those are the conclusions of a new study of 10,000 women in Michigan's Medicare system, which appears in the March issue of Cancer.
"Even with the screening mammography as a covered Medicare benefit ... the majority of older women -- and apparently their physicians -- acted as though getting older was a reason not to have a screening mammography, [even though] the risk for breast cancer increases with age," says study author R. Van Harrison, an associate professor of medical education at the University of Michigan Medical School.
Indeed, the study reports that breast cancer is the second most frequent cancer in women and the second leading cause of cancer-related deaths -- and those risks increase as a woman ages.
Harrison says the most significant breast cancer deaths occur in women over the age of 65. Yet the study shows older women who routinely see their doctor for other health problems, or even just a annual physical, tend to put mammograms on the back burner, he adds.
"Ninety-four percent of older women enrolled in Medicare saw [their doctor] at least once in five years, and 83 percent saw [their doctor] five or more times during this period. Yet 43 percent of older women never had a mammogram, and only 16 percent had one mammogram in five years," Harrison says.
For radiologist Dr. Michael A. Cohen, the findings are "right on the mark" with what he sees occurring in cancer screening every day.
"Many older women view the end of their reproductive cycle as the end of their risks for many cancers, so they stop certain routine screenings, particularly mammograms," says Cohen, who is the medical director of Memorial Sloan-Kettering's Guttman Diagnostic Institute in New York City.
Because cancers generally grow slower in older women, Cohen says this may justify getting a mammogram every two years, instead of yearly. However, he adds, "women should not wait longer than two years -- and they should really make an effort to have one every year, particularly if they are healthy."
The healthier a woman is, he points, out, the better the outcome if breast cancer is diagnosed early.
The new study used data on 10,000 randomly selected women aged 65 or over, gleaned from the files of Michigan's Medicare system, between 1993 and 1997. The goal was to discover how many women had had a mammogram over a five-year period and the number of mammograms they had during that time.
The researchers also looked at factors that might potentially influence a woman's decision to be screened, including age, race, income, education level and interaction with a doctor -- particularly how many times she actually saw a physician during this same time period.
In addition to the main findings, the researchers also say that of the women who did get screened, more than 60 percent did not have regular mammograms every two years as recommended.
Significantly, the women who did get mammograms reportedly did so on the advice of their physicians, particularly obstetrician/gynecologists, Harrison says. This supports previous studies showing that older women say their doctor's recommendation most often prompts them to get a mammogram.
A second study in the same journal makes the same point.
A group of Seattle researchers found that Chinese-American women of all ages do not receive routine breast cancer screens, mostly because of misunderstandings about the effectiveness of mammograms and a lack of physician guidance.
After interviewing 350 Chinese-American women aged 40 and over, the researchers discovered 74 percent of them had had a mammogram. But of those who did, 61 percent hadn't had one in the two years before the study. Those women who did have a mammogram were likely to have a female physician who also was fluent in Chinese, the researchers found.
For more facts on breast cancer in older women, visit National Breast Cancer Quality Improvement Project.
To learn more about the lifesaving power of regular mammograms, check out the American Cancer Society.