Coronavirus vaccinations can cause enlarged lymph nodes in the armpit or near the collarbone, which can be mistaken for a sign of cancer.
As vaccines are rolled out across the country, doctors are seeing more and more of these swollen nodules in people who have recently been immunized, and medical journals have started publishing reports aimed at allaying fears and helping patients to take unnecessary tests. avoid for a harmless condition that will disappear. a few weeks.
The swelling is a normal reaction by the immune system to the vaccine and occurs on the same side as the arm where the shot was given. It can also occur after other vaccinations, including those for influenza and the human papillomavirus (HPV). Patients may or may not notice it. But the enlarged lymph nodes appear as white spots on mammograms and scans on the breast, which look like images that may indicate the spread of cancer from a tumor in the breast or elsewhere in the body.
“I am particularly keen to convey the message to all the patients under supervision after successful prior treatment of cancer,” said Dr. Constance D. Lehman, author of two magazine articles on the problem and head of bust in Massachusetts, said. General Hospital. “I can not imagine the anxiety of scanning and hearing.” We found a large knot. We do not think it is cancer, but can not say: ‘or worse:’ We think it is cancer. ”
The swelling in the armpit was a recognized side effect in the large trials with the vaccines Moderna and Pfizer-BioNTech. In the Moderna study, 11.6 percent of patients reported swollen lymph nodes after the first dose and 16 percent after the second dose. Pfizer-BioNTech apparently had a lower incidence, with 0.3 percent of patients reporting it. But these figures only reflect what patients and their doctors have noticed, and radiologists say the actual rate is likely to be higher and that many more cases are likely to appear on imaging such as mammograms, MRIs or CT scans.
The condition was not listed among the reported side effects in a Food & Drug Administration information document on the Johnson & Johnson Covid vaccine. The agency on Saturday approved the company’s vaccine for emergency use.
Dr Lehman said it was important for imaging centers to ask patients if they had Covid vaccinations and to record the date of the shot and the arm in which it was given.
Her clinic contains this advice in a letter to patients whose examinations detect swelling but have no other abnormalities: ‘The lymph nodes in your armpit area that we see on your mammogram are larger on the side where you are taking the recent vaccine Covid-19 had. Enlarged lymph nodes are common after the Covid-19 vaccine and are your body’s normal response to the vaccine. However, if you feel a lump in your armpit that lasts longer than six weeks after your vaccination, you should notify your healthcare provider. “
One way people can avoid the problem is to postpone routine mammograms and other imaging for at least six weeks after the last dose of vaccine, according to an article by an expert panel in the journal Radiology, published Wednesday.
A professional group, the Society of Breast Imaging, gives similar advice: ‘If possible, and if it does not delay care unnecessarily, consider screening exams before the first dose of a Covid-19 or 4- vaccination. 6 weeks after the second dose. dose of a Covid-19 vaccine. ”
But the expert panel also warns that non-routine imaging, which is necessary to deal with an illness, or other symptoms that may indicate cancer, should not be delayed. Vaccination should not either.
People who have cancer are usually advised to be vaccinated against the coronavirus, especially as they are at greater risk of dying from Covid than the general population. However, some cancer treatments can interfere with the body’s ability to fully respond to the vaccine, and the American Cancer Society advises patients to consult with their oncologists about vaccination.
In people who have recently been vaccinated who have cancer and develop enlarged lymph nodes, it may be necessary to perform more tests, including a biopsy of the nodes, said Dr. Lehman said.
She described one patient with a newly diagnosed breast tumor who had swollen lymph nodes on the same side, and recently received a Covid shot on the side of the arm.
A biopsy was performed, an important step to determine if there are malignant cells in the nodes that can then help determine a course of treatment. It was negative for cancer. The vaccine most likely caused the swelling.
In another case, a woman who previously had cancer in her right breast had a regular mammogram that showed an enlarged lymph node in her left armpit, and no other abnormality. She recently received a Covid vaccination in her left arm. Doctors determined that no more tests would be needed unless the swollen lumps lasted longer than six weeks.
In a man with a history of bone cancer, a CT scan of the breast was performed as part of a follow-up swollen lymph node in one armpit – on the side where he recently had a Covid vaccination. Nothing else was wrong and no further tests were needed. The same decision was made for similar findings in a newly vaccinated man who had a chest CT scan for lung cancer, and in a woman with a history of melanoma.
For patients undergoing cancer in one breast, dr. Lehman said the Covid shot should be given in the arm on the other side. The vaccine can also be injected into the thigh to prevent problems with swelling of lymph nodes.
“It can affect a lot of people if we do not immediately start recording the vaccination status at image centers,” said Dr. Lehman said. “I also want cancer patients to know that they can get the vaccine on the opposite side or even the leg to avoid confusion.”