Why Breast Cancer Screening Fails
Hard-to-Treat Breast Cancer Linked to Missed Mammograms, Detection Failure
Oct. 19, 2004 -- Why does breast cancer screening fail? Blame missed mammograms -- and mammograms that don't detect early breast cancers, a new study suggests.
Screening for breast cancer means regular mammograms. Experts disagree about who should get mammograms and how often they should get them. But most U.S. breast cancer experts agree that women over 50 die of breast cancer at least 30% less often if they get regular mammograms.
Most health plans pay for -- and actively promote -- regular mammograms. But even women with very good health insurance still show up in doctors' offices with advanced, late-stage breast cancer. Why weren't these breast cancers found earlier when they were easier to treat?
That's what Stephen H. Taplin, MD, and colleagues wanted to know. So Taplin, now a senior scientist at the National Cancer Institute (NCI), led a study that analyzed data on 1.5 million women enrolled in seven major health-care plans. They compared 1,347 women with late-stage breast cancers with 1,347 similar women with early-stage breast cancers.
The results surprised Taplin.
"At first we thought we were losing people in the follow-up process after breast cancer detection," Taplin tells WebMD. "But we found that the problem in follow-up is relatively small. It was really screening and detection where the problems were."
The screening problem: 52% of women with late-stage breast cancer hadn't had a mammogram in the last one to three years.
The detection problem: Mammograms failed to find breast cancer in nearly 40% of the women who - in the interval between mammograms -- came down with late-stage breast cancer.
The findings appear in the Oct. 20 issue of The Journal of the National Cancer Institute.
Women Who Miss Mammograms
Some women were more likely to be among those who missed mammograms:
- Women with late-stage breast cancer were nearly three times as likely to miss mammograms if they were age 75 or older.
- Women with late-stage breast cancer were 78% more likely to miss mammograms if they were unmarried.
- Women with late-stage breast cancer were 84% more likely to miss mammograms if they had no family history of breast cancer.
- Nearly 60% of women who missed mammograms were in lower-education groups.
- Nearly 55% of women who missed mammograms were in lower-income groups.
That's a clue to how health plans can do better, says study co-researcher Ann M. Geiger, PhD, group leader for cancer research at Kaiser Permanente Southern California.
"The message is out there: Women need to get screened for breast cancer. But there appears to be a group of women who either don't know they should do this or who don't pursue breast-cancer screening for some other reason," Geiger tells WebMD. "In our study, it isn't lack of insurance. But maybe it's other things, like getting yourself to the clinic on a workday, arranging for child care -- things that become big problems for lower-income women."