Study Shows Breast Screening Women Aged 40-49 Reduces Breast Cancer Mortality

A study led by Queen Mary University of London has found that breast screening women between 40 and 49 years of age reduces breast cancer mortality with minimal increased overdiagnosis, according to a press release.

In the United Kingdom (UK), breast cancer screening programs offer mammography to women 50 to 70 years of age every 3 years. However, uncertainty currently exists regarding whether to start screening at a younger age, including whether it might lead to overdiagnosis of breast cancer, according to the study.

The UK Breast Screening Age Trial randomized more than 160,000 UK women 39 to 41 years of age between the years 1990 and 1997 to receive either annual mammography or the usual National Health Service (NHS) breast screening, which commences at age 50. The primary outcome was mortality from breast cancers diagnosed prior to the first NHS breast screen.

The new analysis of the 23-year follow-up results of the trial found that screening women between 40 and 49 years of age led to a substantial and significant 25% reduction in breast cancer mortality in the first 10 years, according to the study. Further, the total years of life saved from breast cancer in the intervention group was estimated as 620, corresponding to 11.5 years saved per 1000 women invited to earlier screening.

The results suggest that this age group is the worst modest overdiagnosis group and that any over-diagnosed cancers would otherwise be diagnosed at NHS screening from 50 years of age, according to the study authors. They concluded that screening in the age group of 40 to 49 years does not appear to add to over-diagnosed cases from screening at 50 years of age and older.

The study authors said that more research is needed to clarify whether progress in early detection technology and treatment of breast cancer might modify the screening-related reduction in mortality in the 40 to 49 age group. In addition, the researchers did not consider the cost-effectiveness of lowering the screening age.

REFERENCE

Breast screening women in their forties could save lives. Queen Mary University of London. https://www.qmul.ac.uk/media/news/2020/smd/breast-screening-women-in-their-forties-could-save-lives.html#:~:text=Breast%20screening%20women%20aged%2040,at%20data%20from%20160%2C000%20women. Published August 13, 2020. Accessed August 20, 2020.