Part 1: Proactive steps for breast cancer risk reduction: When should I start screening?
Everyone with breasts is at risk of developing breast cancer. But some people are more at risk than others. And, some people are at risk for other diseases that may take priority when weighing their health options. Here we will review the basics of routine screening and risk-reducing options for breast cancer that are available to women.
Other than skin cancer, breast cancer is the most commonly diagnosed cancer in women. We are passionate about sharing our knowledge of breast cancer risk (but, at the same time, there are other cancers and diseases that you and your doctor should be on the look-out for as well). As a side note, heart disease and stroke are responsible for one out of every three female deaths in the US. So, when you are speaking to your doctor about risk reduction and screening options, for any disease, it is important to consider them in the context of your overall health.
Routine mammography screening exists for all women, regardless of personal risk of developing breast cancer. In the future, this may change. Instead of all “average” women beginning mammograms at age 40, on-going clinical trials are studying whether women can start mammogram screening at different ages based on risk level. Doctors are less comfortable reducing screening based on risk, but they are pretty comfortable increasing screening for a woman based on risk—in fact it’s already being done! If a woman has a family history of breast cancer, there is a good chance she is getting earlier, additional, or more frequent screening than the “average-risk” woman is.
Guidelines on when to begin routine mammograms for “average-risk” women differ. Hold-on…it gets a bit confusing. If you are “average-risk” you can get your first mammogram when you are 40, 45 or 50. Why can’t doctors agree on screening age?
While all organizations agree that getting your first mammogram at age 40 saves the most lives, it does lead to “over screening” for women. But, most women are willing to put up with added screening if it means saving a life. Starting screening at 40 leads to 25% fewer deaths from breast cancer compared to starting at age 50.1 All of the following medical bodies advocate for mammography screening to begin at age 40: American College of Radiology (ACR), Society of Breast Imaging (SBI), American Society of Clinical Oncology (ASCO), National Comprehensive Cancer Network (NCCN), National Cancer Institute (NCI) and the American College of Obstetricians and Gynecologists (ACOG).
The American Cancer Society (ACS) has compromised by recommending women get their first mammogram at age 45. The ACS suggests that before 45, it is the woman’s choice.
The United States Preventative Services Task Force (USPSTF) and the American College of Physicians (ACP) recommend women get their first mammogram at age 50, and screen every other year, or biennially. For women under the age of 50, they suggest women “discuss with their physician the benefits, harms, and their personal preferences of breast cancer screening with mammography.” Doctors that follow these guidelines are concerned about overdiagnosis and overtreatment of women and believe that the best balance of harms and benefits of screening include starting at age 50.2
One major benefit to starting screening at a younger age is catching some abnormal changes in your breasts earlier. This can lead to more treatment options if cancer is found and more risk reduction options if abnormal, non-cancer cells are found.
On the flip-side, younger women tend to have denser breast tissue making the chances of a biopsy more likely (80% of biopsies turn out to be negative...doctors take them to be sure cancer is not hiding). Most women are willing to go through a potential biopsy in order to make sure that they don’t have cancer...but it’s a personal decision. This is called a false-positive mammogram result.
Another potential pitfall of earlier screening is detection of abnormal breast tissue that may never turn into cancer (so you may have unnecessary treatment). The problem is, doctors don’t know how to tell if an abnormal cell will progress into cancer, or will just “peter out” and stay abnormal, but never turn into cancer. Therefore, to be on the safe-side, if they see something, they treat it.
The most important takeaway is that all recommendations suggest having a discussion with your doctor about the harms and benefits of beginning mammogram screening at 40. Ultimately it is your choice.
Want some help considering your decision? Here is a checklist you can use to consider your personal risk factors for developing breast cancer. Discuss these risk factors with your healthcare provider—they may make it easier for you to decide when to schedule your mammogram and consider your tolerance for screening results. Women who get a yearly mammogram will have a 50% chance (over a 10-year period) of having at least one false positive result—meaning there is a chance that you will be called back for a repeat mammogram.3
Learn more about GeneType's Breast Cancer risk assessment test.
- Moss SM, Wale C, Smith R, Evans A, Cuckle H, Duffy SW. Effect of mammographic screening from age 40 years on breast cancer mortality in the UK Age trial at 17 years' follow-up: a randomised controlled trial. Lancet Oncol. 2015 Sep;16(9):1123-1132. doi: 10.1016/S1470-2045(15)00128-X. Epub 2015 Jul 20. Erratum in: Lancet Oncol. 2015 Sep;16(9):e427. PMID: 26206144.
- Qaseem A, Lin JS, Mustafa RA, Horwitch CA, Wilt TJ; Clinical Guidelines Committee of the American College of Physicians. Screening for Breast Cancer in Average-Risk Women: A Guidance Statement From the American College of Physicians. Ann Intern Med. 2019 Apr 16;170(8):547-560. doi: 10.7326/M18-2147. PMID: 30959525.
- Schwartz LM, Woloshin S, Sox HC, Fischhoff B, Welch HG. US women's attitudes to false-positive mammography results and detection of ductal carcinoma in situ: cross-sectional survey. West J Med. 2000;173(5):307-312. doi:10.1136/ewjm.173.5.307