An unexpected and concerning side effect of the COVID-19 vaccine is enlarged lymph nodes that show up on positron emission tomography (PET) scans as possible cancer.
As a result, oncologists are reporting that about 10% of patients who had no suspicious findings in their PET scans prior to their vaccine showed positive axillary lymph nodes afterward. Usually findings like that will trigger extra tests such as invasive biopsies and possible treatments for suspected cancer.
Now, researchers who analyzed data from patients who reported suspicious findings on their PET scans after vaccination are saying that providers need to keep their patients’ vaccination status in mind when doing the scans.
MedPage today reported one of the researchers as saying, "Situations where we can really run into trouble are the cancers such as breast, melanoma, lung, and carcinoma … If you are reading a scan for newly diagnosed right-side breast cancer, and you see all of these nodes, your first thought is this is metastatic disease. But then you see that they had a vaccination on that side a week or so ago, and you really don't know if what you are seeing is from cancer or vaccination, because they look exactly the same on imaging."
SOURCE: MedPage Today May 26, 2021