As the prospects for breast cancer treatment have improved, so has the reduction in breast cancer deaths. At the same time, however, the benefits of mammography are waning, as early detection leads to frequent overdiagnosis, while it saves fewer women’s lives.

When mammography was introduced, it was estimated that early detection of breast cancer could prevent about twenty percent of deaths. In Norway, 731 women had to be invited to avoid dying of breast cancer in 1996. In 2016, you had to invite between 1,364 and 3,500 women to get the same results. The reason: “Over the past 25 years, mortality from breast cancer has practically halved. The positive impact of screening is waning as cancer treatments improve,” says Dr. Heinrich Stowering from Aarhus University.

On the other hand, the number of over-diagnosis and over-treatment, a major disadvantage of mammography, remains unchanged: one in five women get a positive mammography result, but have a small lump that does not grow at all or moves so slowly. Growing from the fact that woman can go without examination never seen or felt breast cancer in her life. Stowering explained how overtreatment occurs: “Of course, once a cancerous lump is discovered, it needs to be treated, although this may not be necessary for some women. We don’t know with what. Huh.” In addition, thousands of women each year receive the news that they are suspected of breast cancer – which later turns out to be false.

Source: DOI 10.1093/eurpub/ckac047