Covid- 19 Vaccine and Screening Mammogram findings

COVID-19 vaccines have been reported to cause swelling in the axillary lymph nodes on the side of vaccination (ipsilateral), which can be worrisome to patients and also can be detected on breast screening mammograms.  Here are some suggestions:

  1. For patients that call us concerned about ipsilateral axillary swelling after a vaccine, suggest self-monitoring for up to six weeks post vaccine. If the swelling persists, they will need in person assessment and appropriate imaging. For higher risk patients, eg hx of cancer, consider quicker follow-up.
  2. Try to book mammograms so they are before or at least 6 weeks after the vaccine.
  3. If ipsilateral lymphadenopathy is detected on screening mammogram within 0-4 weeks post vaccination, we should check that the LNs are not palpable within six weeks post vaccine and the radiologist will likely determine the findings are due to the vaccine.
  4. If ipsilateral lymphadenopathy is detected on screening mammogram more than 4 weeks after vaccinations, the radiologist will likely recall the patient for further assessment

Here is some suggested messaging to patients for reassurance:

  • If you recently got the COVID-19 or other vaccine, you may have swelling in the lymph nodes on the side you got the injection (around or in your armpit or neck). This swelling is your body’s normal reaction to the vaccine and is a sign that your body is making antibodies in response to the vaccine.
  • If lymph node swelling is seen on your imaging test, the radiologist may ask you to come back for additional imaging to check that the swelling has gone away
  • If you notice swelling in your lymph nodes after vaccination, and it lasts for more than 6 weeks after your vaccination, you should let your primary care provider know