Should I worry about radiation from a mammogram?

Dear Breast Friend, My doctor is encouraging me to get a screening mammogram to check for breast cancer, but I am worried about the radiation from the exam. I thought radiation caused cancer, why would we use radiation to look for cancer? Sincerely, Concerned and confused

Dear Concerned,

Great question! It is common to feel like any amount of radiation is too much radiation, but we are all exposed to radiation every day just from living on earth. Radiation is a type of energy; when the cells of our body are exposed to radiation energy, many things can happen. A lot of the energy will pass through the cell, but sometimes the energy can cause damage to the cell as it passes through which can in turn sometimes result in cancerous change. Mammograms are formed by recording how much radiation passes through cells in breast tissue. Some fears about radiation are well-justified, but with radiation both dose (amount) and duration (length) of exposure matter.

The good news is that the radiation dose received from a mammogram picture is very low. Also, the radiation given during a mammogram is very closely monitored and required to be below a certain threshold. A routine mammogram has 0.4 mSv of radiation. For comparison, this is the same amount of radiation you would be exposed to from eating a typical diet for 6 months, taking 5 round trip cross country flights, or just living on earth (background radiation) for 7 weeks. Yes that’s right, you are exposed to radiation any time you give into a snack attack. In the case of a banana for example, a small fraction of the potassium in bananas naturally occurs as the radioactive potassium-40 isotope exposing your to radiation.

The low levels of radiation experienced from a typical mammogram are not high enough to cause cancers to develop, but the information we get from a screening mammogram helps us catch cancers before they are able to be felt, when they are in their earliest and most treatable stages. Since screening mammography has been accepted into widespread practice in the late 1980s, we have seen a decrease in breast cancer deaths of over 40 percent! If mammograms caused cancer, the opposite would be true.

According to the National Institute of Health, “modern digital mammography and digital breast tomosynthesis typically uses radiation doses far less than the mandated upper limit. It is estimated that a woman undergoing annual screening mammography from age 40 to 49 will develop a fatal radiation-induced breast cancer on average once every 76 000 to 97 000 years.” In order to reach the level of radiation dose needed to increase your risk of breast cancer, you would need to have 250 mammograms all at one time! Those are pretty small chances for cancer.

Conversely, the average woman has a lifetime risk of having breast cancer of approximately 12.5% and for many women with certain risk factors (link) the chances for breast cancer can be even higher. Since breast cancer is most treatable and has the best prognosis when it is caught when it is small and early stage, the benefit of early detection though mammography far outweighs concerns about the effect of a small radiation does. Additionally, higher doses of radiation are sometimes used as a treatment for breast cancer. This is a situation where an ounce of prevention is better than a pound of cure! So, Concerned, we ar GRACE breast imaging agree with your primary physician that you should schedule that screening mammogram and keep to an annual schedule to maximize your breast health. The physcians at GRACE are committed to the safety and well-being of our patients. That is why our physicians and staff have taken the pledge to Image Wisely®.

You should feel confident in your decision to participate in a breast cancer screening program because you are being pro-active in taking charge of your breast health. You should also feel at ease that we at GRACE breast imaging pledge to adhere to the ALARA principal, which means that we will use radiation dose As Low As Reasonably Achievable to maximize the information on your mammogram while keeping the radiation dose well below the national limit for mammography exams.