Most Women Unaware Of Mammography Downside
A
DGReview of :"US
women's attitudes to false positive mammography results and detection of ductal
carcinoma in situ: cross sectional
survey"
BMJ
06/16/2000
By Bruce Yates
An overwhelming majority of women know a mammogram can produce a
false-positive result, but only a small minority know it possibly can detect a
non-progressive cancer, American researchers have found.
A survey of 479
women aged 18 to 97, and who did not report a history of breast cancer, were
asked if they knew about false-positive readings, what they felt about them, and
what they knew about ductal carcinoma in situ detected by
mammography.
Overall, 63 per cent of the women thought a ratio of 500
false-positives per life saved was reasonable, and 37 per cent said they would
go along with as many as 10,000 such false positives. A similar attitude was
found among 76 of the women who themselves had had a false positive mammogram.
"One explanation for this high tolerance is that women have an overly
optimistic sense of the benefit of mammography," researchers said. "We found no
evidence to support this explanation. No respondent thought screening
mammography reduced the chance of dying from breast cancer."
On the flip
side, researchers found that only eight per cent of the women thought that
mammography could harm a woman, such as detecting a non-progressive cancer,
which could lead to unnecessary invasive treatment. Ninety-four per cent said
they doubted such a possibility.
Many women became concerned once they
were informed about non-progressive cancer. Younger women, in whom 90 percent of
the cancers found by screening mammography are ductal carcinoma in situ,
were the most interested.
"Although experts on screening have focused
much attention on the anxiety experienced by women with false-positive
mammograms, we believe clinicians counselling women about mammography should
spend less time reviewing what most women know and accept that is, that false
positives are part of screening. In contrast, more time should probably be spent
educating women about the less familiar outcome of the ambiguity associated with
the detection of ductal carcinoma in situ," researchers
conclude.
