Swollen lymph nodes are a natural reaction to the COVID-19 vaccine. Experts say people should still get vaccinated and not delay overdue mammogram appointments.
The Centers for Disease Control and Prevention (CDC), citing a study in the journal Preventive Medicine, said there was a sharp decline in breast cancer screenings at the onset of the COVID-19 pandemic. The federal health agency warned, “Prolonged delays in screening related to the COVID-19 pandemic may lead to delayed diagnoses, poor health consequences, and an increase in cancer disparities among women already experiencing health inequities.”
The American Cancer Society says women as young as 40 at average risk for breast cancer should get a mammogram every year. With tens of thousands of women getting vaccinated against COVID-19 this year, VERIFY viewer Mydia A. had a question about what kind of impact the vaccine could have on breast cancer screenings.
Mydia asked: Can the COVID-19 vaccine lead to a false-positive mammogram?
Yes, the COVID-19 vaccine can lead to a false-positive mammogram.
WHAT WE FOUND
The COVID-19 vaccine can cause swollen lymph nodes under the arm that received the injection, according to the American Cancer Society.
“Swollen lymph nodes under the arm might show up on a mammogram done to screen for breast cancer, which could cause concern and might lead to the need for further tests,” the American Cancer Society says on its website.
Lisa Mullen, a radiologist at Johns Hopkins University, said those enlarged lymph nodes can result in a false-positive mammogram.
Swollen lymph nodes are a natural reaction for the body in response to the COVID-19 vaccine, according to Kaiser Permanente.
“Just as some people feel soreness or swelling at the injection site, or experience a low-grade fever, chills, headaches or muscle aches, swollen lymph nodes are evidence your body’s immune system is doing what it should, making antibodies and training other cells to protect you,” the health care company says.
Other vaccines have been known to cause similar side effects. Mullen said the flu, shingles, pneumonia and D-TaP (diphtheria/tetanus/pertussis) shots can change the appearance of lymph nodes.
Enlarged lymph nodes caused by the body’s response to the COVID-19 vaccine are temporary. Kaiser Permanente said lymph nodes could be enlarged for four to six weeks after vaccination before returning to normal size.
Despite the possibility of a false-positive mammogram, Mullen and Kaiser Permanente said people should get the COVID-19 vaccine as soon as possible.
So, when should people schedule their mammogram appointments to avoid a false positive from the COVID-19 vaccine? The American Cancer Society recommends not delaying a mammogram screen without first speaking with a doctor.
The Society of Breast Imaging advises people to schedule their mammogram screening before they receive their first COVID-19 vaccine dose or wait at least four weeks after receiving the second dose, if possible. However, the group says people overdue for a screening exam should not delay and still schedule their appointment even if it’s during the vaccine regimen.
“Regular screening mammograms ensure that breast cancer can be detected as early as possible,” the Society of Breast Imaging says.
People recently vaccinated against COVID-19 should tell their doctor at their mammogram screening appointment.
“Tell her when you received the vaccine, and which arm the vaccine was given,” the Society of Breast Imaging advises. “State whether it’s your first or second dose. This information will help the breast radiologist interpreting your screening mammogram.”
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