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Tumor Discovery Benefits and harms of screening breast cancer

smaller. The most exhaustive evaluation was that of a longer effective [8,9] . This finding has led to the abolishment
Cochrane review in 2009 , which included six studies and of screening mammography by the Swiss Medical Council
[4]
600,000 women. After accounting for the biases identified in 2014 .
[10]
in those studies, the RRR of mortality was in fact half of the The importance of women making informed decision
aforementioned (15%), or what amounts to the same thing, to accept screening or not has been emphasized, and an
that it was necessary to screen 2000 women in ten years evidence-based informative booklet that is available in
(twice as much) for one to benefit compared to the group several languages has also been published .
[11]
that was not screened (absolute risk reduction: 0.05%).
On the other hand, this benefit was non-existent when In a comprehensive review of scientific literature,
[12]
evaluating the overall mortality since it was the same in both published in The BMJ, Prasad et al. have found that
the groups, which could be ascribed to the consequences disease-specific mortality is an unreliable proxy for overall
resulting from overtreatment in the screening group. mortality. Even when a screening technique lowers disease-
specific mortality rates, which is generally rare or only to a
The relevance of overdiagnosis and overtreatment was
also acknowledged in consideration of the cumulative risk slight degree, there are no significant differences in overall
mortality. Negative effects of screening may override any
of false positive results. Overdiagnosis reached 30% that
is to say that 10 healthy women (who if there had been disease-specific benefits.
no screening would not have been overdiagnosed) were If screening does not reduce the risk of mortality
treated unnecessarily, and although no one can say with from cancer (including breast cancer), why are screening
certainty which women have overtreated tumors, there is campaigns so successful?
certainty about what happens to them: they would have
to undergo surgery, radiotherapy, hormonal therapy for 3. Misinformation and misrepresentations:
5 years or more, chemotherapy, or a combination of all Misconceptions by women
of these to treat abnormalities that otherwise would not In 2014, Biller-Andorno and Jüni revealed the enormous
[10]
have caused disease . It has been warned that repeated discrepancy between women’s perceptions of the benefits
[5]
screening increases the risk of overdiagnosis as shown of mammogram and those expected in reality. Of 1003
by the risk ranging from about 20–60% after 10 years of women questioned, 71.5% believed that mammogram can
mammography screening. reduce the risk of mortality from breast cancer by at least
The review revealed for the first time that psychological half, while 72.1% believed that it can prevent at least 80
harm from breast cancer screening is substantial and long- deaths/1000 women screened. Nothing could be further
lasting, affecting a large number of healthy women (over from reality than this.
200 women experienced significant psychological harm).
He concludes that promoting mammography screening
In 2011, the National Breast Cancer Coalition (NBCC) , is easy if most women believe that it prevents or reduces
[6]
after two exhaustive reviews on screening, concluded that the risk of breast cancer and saves lives through early
the general impact on mortality is small and that the existing detection of aggressive tumors. We would be in favor of
biases in the trials could either “erase it” or “create it.” mammography screening only if these beliefs were valid.
Mammography, which has many limitations, does not Unfortunately, they are not, and we believe women need
prevent or cure breast cancer. Women should discuss with to be told that.
their physicians their own risk profile, the potential benefits 4. Incorrect information
and harms, the complexities of screening mammography,
and then make informed decisions about the screening. Screening advocates and their organizations often
Women who have symptoms of breast cancer, such as a emphasize the benefits while omitting information on
lump, pain, or nipple discharge, should have a diagnostic major harms when providing information materials .
[7]
mammogram performed. In 2016, Gigerenzer , in his editorial in The BMJ,
[13]
The update on the Cochrane database review, carried which is attached to the review by Prasad et al. , stressed
[12]
out in 2013 , found no positive effect of screening on on the influence of language and the persuasiveness of
[7]
mortality from breast cancer, nor on overall mortality. They words. Instead of saying “early diagnosis,” supporters of
believe that due to advances in breast cancer treatment screening use the term “prevention.” This erroneously
and increased general awareness, the absolute effect of suggests that screening lowers the chance of developing
screening was likely to be less than that shown in the trials. cancer. Does this then imply that not getting screened for
In fact, recent studies have suggested that screening is no cancer increases the risk of developing cancer?

Volume 1 Issue 2 (2022) 3 https://doi.org/10.36922/td.v1i2.228