According to a new study, 3D mammography is proving to be much more effective for women over 65 years of age to screen for breast cancer. Responsible for fewer "false positives", this technique would also detect early tumors.
Breast cancer is both the most common and the most lethal in women. Every year in France, 59,000 new cases are detected and nearly 12,000 women die. Yet, breast cancer can be cured in more than 9 out of 10 cases when it is detected early. Hence the importance of being screened every year by palpation for women over 25 and by mammography, every two years, from 50 years.
Generally performed in 2D, mammograms remain an effective method for screening for breast cancer in women 65 years and older. However, according to a new study published in the journal Radiologythis technique would be more effective in older women if it was systematically performed in 3 dimensions.
Fewer false alerts
Called tomosynthesis, 3D mammography produces series of cuts of one millimeter thick. It thus makes it possible to avoid the superposition effect of the mammary tissues because it reconstructs the image of the breast three-dimensionally from several low-dose radiographs acquired at different projection angles. Still little used a few years ago, 3D mammography is now widely used in addition to conventional mammography, and recommended by the High Authority of Health, which considers that it "could improve the clinical performance of cancer screening. within. "
This is also the opinion of the authors of these new works. To measure the added value of 3D mammography on screening for older people's cancers, they compared conventional screening mammograms of more than 15,000 women, averaging 72.7 years old, with those of more than 20,000 women of a similar age having undergone a tomosynthesis.
While both techniques were found to be effective, they found that 3D mammography had additional benefits such as reducing the number of false positives. Tomosynthesis has also been shown to have a higher positive predictive value and a better ability to distinguish between cancer and benign tumor.
"We have shown that screening mammography works well in older women, with high levels of cancer detection and low false positives, and that tomosynthesis leads to even better performance than conventional 2D mammography," explains Dr. Manisha Bahl, a radiologist at Massachusetts General Hospital and an assistant professor of radiology at Harvard Medical School. "For example, the rate of abnormal interpretation, that is, the percentage of women who are recalled for additional imaging after a screening mammogram, is lower with tomosynthesis than with conventional 2D mammography. We also found that fewer cancers detected by tomosynthesis were positive for the lymph nodes, which suggests that we detect cancers at an earlier stage, "says the researcher.
1 in 2 women are not screened
The results of the study do not support a specific age limit for mammography screening. According to Dr. Bahl, guidelines for screening older women should be based on individual preferences, life expectancy and health status, not just age.
Currently in France, women aged 50 to 74 are invited to have a mammogram and a clinical examination every two years. Although these exams are covered 100% by the Health Insurance, only 49.9% of the women concerned responded positively in 2017 to the invitation that was made to them in the framework of the organized cancer screening program. breast.