Dr. Jacqueline Gerhart: Yearly Mammogram Might Not Be Necessary
Madison, Wisconsin - UW Health Family Medicine physician Jacqueline Gerhart writes a column that usually appears weekly on madison.com and in the Wisconsin State Journal. Columns are re-published here with permission.
Dear Dr. Gerhart: I heard on the radio that a new study shows that women may no longer need a yearly mammogram - and that they can wait two years. Is that true?
Dear Reader: There are quite a few misconceptions in the general public about breast cancer screening. This is likely because the guidelines have changed over time. Women who were told in the past to get their yearly mammogram and their yearly pap smear may be pleasantly surprised that they may not need to have these screening tests performed quite as often.
Since December 2009, the United States Preventive Services Task Force (USPSTF) has recommended that women aged 50 to 74 should get mammograms every other year. They do not state that a yearly mammogram is necessary. They do not recommend mammograms prior to age 50, stating screening earlier than age 50 is an individual decision between patient and provider.
Evidence on whether to get mammograms starting at age 40, and whether to get them on a yearly basis has been controversial. In fact, groups, such as the American Cancer Society and the American College of Obstetrics and Gynecology have advocated for getting annual mammograms starting at age 40. However, our nation's breast cancer guidelines may soon be revised, partly based on the new study that you are referring to.
The study is a well-designed, population-based study from Canada. Starting in 1980, they enrolled 89,835 women aged 40 to 59, and randomly assigned them into two different groups: one with breast exams only, and ones with yearly mammograms and yearly breast exams. Then they followed the patients for 25 years to see how many got breast cancer, and how many died from breast cancer. In other words, they wanted to see if getting yearly mammograms increased the likelihood of detecting cancer early and therefore prevented more cancer deaths.
Their data showed that in both groups, the number of breast cancer diagnoses and the number of breast cancer deaths were about the same. Over the 25 years, about 3,200 women in both groups were diagnosed with breast cancer, and of those, about 500 died. Furthermore, in the mammogram group, there were about 100 patients who had "over-diagnosed" cancer - which means they received treatment for what was thought to be cancer on mammogram, but then turned out to not be cancer. The authors concluded that about 1 in every 400 patients will have a mammogram finding of cancer when it really isn't.
They concluded that getting mammograms between the ages of 40 and 49 does not change your risk of dying from breast cancer.
Please note, this is just one study. In other studies, there has been evidence that early mammograms can find cancers before you can feel a lump. And, that this "early diagnosis" can help decrease your chance of breast cancer death. However, some of these studies were done prior to having advanced treatment techniques and drugs for breast cancer. And some of these treatments allow us to treat the cancer more quickly and effectively - thus, perhaps, making very early detection less necessary.
Stay tuned, however. Experts are working to come up with consensus recommendations. For now, be sure to ask your health-care provider what screening schedule is correct for you.
This column provides general health information and is not specific advice intended for any particular individual(s). It is not a professional medical opinion or a diagnosis. Always consult your personal health care provider about your concerns. No ongoing relationship of any sort (including but not limited to any form of professional relationship) is implied or offered by Dr. Gerhart to people submitting questions.
Date Published: 02/26/2014