Starting annual screening mammograms at age 40 saves life. Despite this fact, depending on who you ask, confusing recommendations remain, with some organizations recommending delaying screening until age 50. The thing is, there is no scientific or biological reason that the age of 50 was selected as the age to begin screening. It is scientifically proven that breast cancer incidence increases substantially around age 40, with one in 6 women diagnosed with breast cancer being a woman in her 40’s.
Starting screening at age 40 results in the greatest mortality reduction, with current research proving between 30-40% reduction in breast cancer deaths since mammography screening became widespread in the early 1990s. Not initiating screening at age 40 would be detrimental to women in the 40–49-year age group. Their cancer would clinically present later as a palpable mass, more advanced in stage, and more difficult to treat successfully. As the goal of screening is to detect breast cancer early, it is imperative to screen at age 40 to give women the best opportunity for just that, early detection.
It is confusing for women when major health organizations present different guidelines regarding when to start screening and how frequently. But it is important to note that every major American medical organization with expertise in breast cancer cases (American Congress of Obstetricians and Gynecologists, American Cancer Society, American College of Radiology, National Accreditation Program for Breast Centers, and Society of Breast Imaging) all agree starting at age 40 saves the most lives. Updated breast cancer screening guidelines from the ACR and SBI (June 2021) highlight the importance of annual screening for all women.
Those in disagreement with this place more importance on the risks they perceive with mammography instead of the benefits. They worry about the anxiety a woman feels after a false alarm, such as a callback, or the potential for overdiagnosis, which identifies a tumor that may not advance during the woman’s lifetime and leads to unnecessary treatment. However, the research does not support these concerns. The anxiety women feel after a call-back is short-term, and in fact, research has shown that even after a call-back, women still support routine screening. The overdiagnosis theory is frequently overhyped, with the real overdiagnosis rate cited by experts as less than 10%.
Science at this time cannot tell for certain which small tumors will progress to deadly cancer versus some that will grow very slowly over time; therefore, all women 40 years and older should be screened annually. Mammography screening beginning at 40 results in the most lives saved and the most life-years gained.