As more people are vaccinated against COVID-19, physicians are noticing an uptick in the number of people with enlarged lymph nodes in the armpit area, which can be mistaken as a sign of cancer on routine imaging such as mammograms and CT scans, The New York Times reported March 1.
Swollen lymph nodes are a common immune system reaction to vaccinations and can also occur after getting the flu shot or HPV vaccine. The swelling typically subsides within a few weeks and occurs on the same side of the body where the vaccination was administered.
In response, medical journals and physicians have issued a number of recommendations to avoid the confusion. The Times referenced a research letter published in Radiology Feb. 24 that recommended postponing routine mammograms and other imaging for at least six weeks after the final vaccine dose. Scheduling screening exams before receiving the first dose is another option.
Constance Lehman, MD, PhD, chief of breast imaging at Boston-based Massachusetts General Hospital, told the news outlet that imaging centers should check to see if patients have been vaccinated, recording when they received the shot and on which side. Dr. Lehman's clinic has started giving recently vaccinated patients who showed swelling on their imaging an advisory letter informing them that it's a normal reaction to vaccines and to consult their provider if they feel a lump in their armpit after more than six weeks post-vaccination.
For patients who have cancer and develop swollen lymph nodes, additional testing or a biopsy may be needed to rule out cancer spread, Dr. Lehman added.
"This could really impact a lot of people if we don't start recording vaccination status immediately at imaging centers," Dr. Lehman said.
To read the full New York Times article, click here.