In this randomized, controlled trial of 23 breast screening units across Great Britain, 160,921 women were randomly assigned to an intervention group (n=55,883) consisting of yearly mammographic screening from the year of trial inclusion up to and including the year they reached 48 years of age, or a control group (n=106,953), consisting of standard care with no screening until the age of 50. The primary endpoint was defined by the researchers as mortality from breast cancers diagnosed in the intervention period of the trial.
According to the results, there was a notable decline in breast cancer mortality at 10 years of follow-up. They observed 83 breast cancer deaths in the intervention group compared to 219 in the control group (RR=0·75; 95% CI, 0·58 to 0·97];p=0·029). They observed no significant reduction thereafter, with 126 deaths versus 255 deaths occurring after more than 10 years of follow-up (RR=0·98; 0·79 to 1·22; p=0·86).
— Medical Xpress (@medical_xpress) August 12, 2020
The authors concluded, “Our results suggest a reduction in breast cancer mortality with annual mammography in women aged 40–49 years within the first 10 years of follow-up, and no overdiagnosis in addition to that which arises from screening at age 50 years and older. Further evaluation of screening in women younger than 50 years, with modern screening and treatment protocols, is warranted.”
Agree! 75% of breast cancers occur in women with no known risk factors and 1/6 occur in women in their forties. Instead of “targeting” that reduces access to screening, let’s work on targeting that saves lives by identifying and improving access to screening for high risk women. https://t.co/W2optv1kfG
— Nina Vincoff MD (@NinaVincoffMD) July 7, 2018
Breast screening women in their forties saves lives https://t.co/thrfaj3Ndy
— Science Codex (@sciencecodex) August 13, 2020