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Personalized breast cancer screening can prevent unnecessary mammograms


Avoid unnecessary mammograms: Individual breast cancer screenings
In Germany, around 70,000 women develop breast cancer every year. Breast cancer is the most common tumor in women in Germany. As a rule, the chances of recovery increase the earlier the tumor is discovered. In order to improve preventive care, it would make sense to invite women for early diagnosis based on their individual risk of illness.

Better chances of recovery with early diagnosis
Breast cancer, also called breast cancer, is the most common malignant tumor in women. Around 70,000 new cases are counted annually in Germany alone. The chances of a cure usually increase the earlier the tumor is discovered and the more precisely it can be diagnosed. Mammography screening is used to detect cancer early. According to some experts, there are only three percent misdiagnosis. The German Cancer Research Center (DKFZ) now points out that many unnecessary examinations could also be avoided.

Avoid unnecessary mammograms
Women from 50 to 69 years old can participate in the breast cancer screening program free of charge, but in some places only about every second person goes to mammography screening. Some women are afraid of the exam - it is not entirely painless.

Even though it is known that the examination does not offer a guarantee, according to experts, more than 17,000 carcinomas could be detected by mammography screenings within one year.

However, many unnecessary mammograms and thus many false positive results could be avoided if women with a low risk of breast cancer were invited to mammography at longer intervals, but women with a high risk could take the exam closely, writes the DKFZ in a recent report.

But how can the individual breast cancer risk of a woman be determined as precisely as possible? Scientists at the DKFZ want to improve the calculation models used for risk assessment. Blood samples collected from the EPIC study will help.

Tumor discovered in curable stage
Experts currently believe that out of 1,000 women who go to mammography regularly for ten years, about one or two are saved from breast cancer death because their tumor has been discovered at a still curable stage.

Critics of mammography contrast this potential benefit with possible disadvantages: radiation exposure, unnecessary anxiety in the event of a false positive finding and overdiagnosis, i.e. the discovery of slowly growing tumors that would have been no problem during life.

"The situation could be improved by personalized early detection, which is adapted to the individual breast cancer risk," says Rudolf Kaaks from the DKFZ.

He explains: “On the one hand, there is the benefit of mammography, namely reduced breast cancer mortality. This contrasts with the risks such as overdiagnosis, false positive results and ultimately also the costs. Our goal is to shift this balance towards benefit. ”

Greatest benefit for women at high risk of breast cancer
Women with a high risk of breast cancer, i.e. with a higher probability of actually being affected by a tumor, naturally have the greatest benefit from the examination.

“These women could be offered close-meshed mammograms, and they might even want to start screening at the age of 45. In contrast, in women with a lower risk, longer intervals between the mammograms would suffice. ”

But how can a woman's individual breast cancer risk be determined? Scientists have developed mathematical models for this prediction.

The models are primarily based on data from the history of reproduction: At what age did the first menstrual period take place? When was the first child born, how many children were there in total? When did the menopause start? Has hormonal contraception been used or has hormone replacement therapy been taken? The body mass index is also included in the current risk assessment models, as is the number of cancer cases in direct relatives.

Annika Hüsing from Rudolf Kaaks' department was recently able to show that the models become even more accurate when the hormone level is factored in. This applies at least to women after the menopause.

For this work, the scientist used blood samples from participants in the EPIC study - the major European study on nutrition, lifestyle and cancer. The concentrations of the sex hormones estradiol and testosterone determined in these samples were incorporated into the model and significantly improved the predictive power.

Further improve screening tests for cancer screening
The prediction models are not designed for women who are known to have a mutation in the famous “breast cancer genes” BRCA1 and BRCA2 and who are therefore at extremely high risk of developing breast cancer.

In addition to the BRCA mutations, there is a multitude of smallest gene variants in the genome of every human being, each of which has only a minimal influence. Taken together, however, they can significantly increase the risk of breast cancer.

The extent of this influence is currently being determined by scientists in large international research consortia, in which the DKFZ epidemiologists around Kaaks are also involved. These genetic risk profiles are to be included in the models as additional biological markers.

It is also important to adapt the calculations to the respective population. Anne Hüsing is in the process of adapting the usual mathematical models based on data from the USA to German conditions:

“With us, women are older when they give birth to their first child, and they have fewer children overall than women in the United States. The prescription of hormone therapies is also handled differently. ”

"The challenge now is to bring all of these calculations together," says Kaaks, adding: "Screening tests for early cancer detection affect millions of people. We therefore have to constantly check whether and how they can be improved further. ”(Ad)

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Video: Screening for Breast Cancer: Mammography English (June 2021).