Mammogram Results After the Covid Vaccine: What You Should Know & Why Not to Worry

Whether you have been vaccinated for COVID-19 or not, you should not delay your screening mammogram.  Getting regular screening mammograms keeps you safer by catching breast cancers early when they might be easier to treat.

But, you should let your mammography technologist know if you’ve been vaccinated for COVID-19, how many doses you’ve received, and in which arm it was administered. That’s because the COVID-19 vaccine can temporarily cause benign findings on screening mammograms.

In this blog, we’ll talk about the changes the vaccine can cause on mammograms, what you should know and why not to worry.

Screening Mammograms During The Pandemic

At the beginning of the COVID-19 pandemic, to help slow the spread of the virus, and to direct resources to treat people who were infected with the virus, most hospitals, and other healthcare facilities delayed or canceled elective procedures. At the beginning of 2020,  screening mammograms came to a halt. By the summer of 2020 care slowly resumed at reduced capacity and recently the numbers are climbing back towards pre-pandemic levels. However, there remains a large backlog of missed visits.

Fortunately, most patients with symptoms or prior abnormal results were prioritized and continued to receive care during the pandemic.

How The COVID-19 Vaccine Might Affect Your Mammogram

There is no connection between the COVID-19 vaccine and breast cancer, or any type of cancer. But, the COVID-19 vaccine can cause temporary lymph node enlargement in some people and result in a “false positive” mammogram.  On mammograms, the enlarged nodes related to the vaccine have the potential to be mistaken for signs of breast cancer or other cancers such as lymphoma and result in additional testing, and unnecessary stress and anxiety.

Why Does The Vaccine Cause Lymph Node Enlargement In Some People?

Some people react strongly to vaccines such as the COVID-19 vaccine, some shingles vaccines, pneumonia, flu vaccines, and others. They can develop enlargement of the lymph nodes under the arm as part of the normal immune response to the vaccine. This is seen in about 10 percent of people. The heightened immune response is normal and expected.  Your lymph nodes will return to normal size a few weeks after your vaccination regimen is complete

What To Know Before Scheduling Your Screening Mammogram 

Because inflammation due to the vaccine might appear as a breast lump or lymph node swelling that may be misleading on imaging, the Society of Breast Imaging recommends that women schedule their annual screening mammograms either prior to their first vaccine dose or 4 weeks to 6 weeks after the second dose. 

Another option is to have the vaccine administered in your thigh instead of your arm to decrease the chance of lymph node swelling in your armpit.

If you do receive a mammogram less than four to six weeks after your shot, make sure you tell the technologist which vaccine you received, when you got it, and in which arm so she can alert the radiologist and potentially avoid unnecessary workups and concerns..

Mammogram Results After The Covid-19 Vaccine: Final Thoughts

If you’re eligible for the COVID-19 vaccine, or if it’s time for a baseline or routine mammogram, please don’t put off either! 

Lymph node enlargement in the armpit is a normal reaction to the COVID vaccine, and nothing to worry about. It just means your immune system is doing its job.

The most important thing to understand is that there is no danger of breast cancer associated with the COVID-19 vaccine, and you should plan on getting your vaccines as soon as you are eligible.

The Society of Breast Imaging recommends that women schedule their annual screening mammograms either prior to their first vaccine dose or 4 weeks to 6 weeks after the second dose.