Mammograms at age 40? Yes, please.
Last week, the influential U.S. Preventive Services Task Force proposed a revision to their breast cancer screening guidelines to lower the age of starting mammograms from 50 to 40. This is an important change that, if adopted, would increase early breast-cancer detection.
Breast cancer is the most common cancer among American women. About
1 in 8 women in the United States will develop breast cancer in their lifetimes. It is the second-leading cause of cancer death, claiming the lives of around 42,000 women every year.
Early diagnosis is crucial. When breast cancer is detected before it can spread to the lymph nodes and other parts of the body, the fiveyear survival rate is 99 percent. When detected after the cancer has metastasized, it declines to 30 percent.
In recent years, there has been a steady increase in younger people being diagnosed with cancer. Between 2015 and 2019, breast-cancer diagnoses among women in their 40s have risen an average of 2 percent a year. A large 2020 British study reported that mortality from breast cancer could be reduced by lowering the starting age of mammography to 40.
This is especially essential for Black women. A study published in JAMA Network Open found that the rate of breast-cancer deaths among Black women in their 40s was 27 per 100,000 person-years, compared with 15 per 100,000 among White women. Another study by the American Cancer Society reports that only 57 percent of breast cancer in Black women were detected at a localized stage compared with 67 percent in White women. The task force reviewed these and other new evidence and concluded that there was a “moderate benefit” to lowering the age of recommended mammograms to 40 — that is, the benefit of earlier cancer detection outweighs the harm of potentially unnecessary tests and the possibility of false-positive results.
This change, if finalized after the public comment period, would more closely align guidance among major national entities. The American College of Obstetricians and Gynecologists already recommends women to receive mammograms beginning at age 40. The American Cancer Society’s guidelines recommend women start at age 45, with an option to begin earlier at 40.
The recommendations differ in some respects. The task force calls for mammograms every two years from age 40 to 74. The American College of Obstetricians and Gynecologists recommends them every one to two years from 40 until “at least age 75 years.” The American Cancer Society guidelines say that women ages 45 to 54 should be screened annually, then transition to biennial screening — though can choose annual screening if they wish — for as long as they are in good health and have a life expectancy of 10 years or longer.
These recommendations apply only to women at average risk of breast cancer. Those with higher risk might start screenings earlier and with additional imaging studies. This includes anyone who’s had a first-degree relative (such as a sister, mother or daughter) with breast cancer; a breast-cancer diagnosis themselves; genetic testing positive for mutations such as BRCA; or prior radiation to the chest.
I fall into this higher-risk category myself. My mother was diagnosed with metastatic breast cancer when she was in her mid40s. In close consultation with my primary-care physician, I began annual breast-cancer screenings in my mid-30s. Because I have dense breast tissue, which could obscure mammography findings, I also go for a breast MRI exam every year.
Twice, I’ve had a finding that warranted further investigation. While it was distressing to go through the process of pursuing what ended up being a false-positive, it would have been far worse to be diagnosed at a later stage, as was the case with my mother, who ended up dying from her cancer.
My takeaway for patients wondering how to make sense of the changing guidance is to begin by determining their risk of developing breast cancer. If they are high-risk, these screening guidelines don’t apply to them. They should speak with their physician about when to start mammograms, how often to do them and what additional studies might be needed.
Those at average risk should start mammograms at age 40. Because recommending entities differ in testing frequency, women can decide whether they’d prefer a yearly mammogram or one every two years. Patients who want additional reassurance could opt for the former, while those who prioritize reducing health-care visits could choose the latter. (The Affordable Care Act requires insurance companies to cover screening mammograms, so costs should not be a determining factor for most people.)
Every time I go for my mammogram or MRI, I am anxious. I remember vividly my mother telling me about her cancer diagnosis, and every year, I know that there is a chance I could have a result that prompts a similar conversation with my family. But if I have cancer, I’d want to know as soon as possible.
Indeed, this is why cancer screening is such a critical part of routine preventive care: Early detection, followed by prompt treatment, saves lives.