A side effect of the vaccine can simulate signs of breast cancer, according to doctors.
(Courtesy of the University of Utah Health) One vial of the Pfizer version of the COVID-19 vaccine. Doctors are warning patients that they should postpone mammograms for a month after giving the last dose of the vaccine, because of a side effect that simulates a condition often seen in cancer diagnoses.
Health experts across the country, including a prominent Utah physician, are warning women taking the COVID-19 vaccine to wait at least a month before having a routine mammogram – because of a side effect of the vaccine that mimics a condition often seen in cancer diagnoses.
“We don’t want patients to get these false positives, to have that kind of alarm,” said Dr. Brett Parkinson, medical director of the Breast Care Center at Intermountain Healthcare.
Parkinson said doctors at the center, as well as doctors across the country, noticed that some people who get the COVID-19 vaccine have the side effect of swollen lymph nodes in the armpit or underarm area. By itself, this swelling is not serious and usually resolves within four weeks.
“Your body is developing an immune response, and that’s a good thing,” said Parkinson.
However, when this swelling in the armpit lymph nodes appears during a routine mammogram, said Parkinson, a doctor would likely call the patient back for a more detailed examination. This swelling, he said, could be a sign of metastatic breast cancer – a cancer that has spread beyond the breast – or lymphoma or leukemia.
The side effect appears in 11% of patients after the first dose of the Modern version of the COVID-19 vaccine, and 16% of the time after the second dose, Parkinson said. He added that experts expect similar findings from patients receiving the version of Pfizer.
“We started looking at this and realized that if we don’t do something, we will have a lot of patients coming back unnecessarily [to their doctor] for those enlarged lymph nodes, ”said Parkinson.
Parkinson said signs were placed at Intermountain’s Breast Care Center in Murray, and at other Intermountain sites that do mammograms, telling patients that – except for other symptoms, such as a lump in the breast – they should postpone the mammogram until four weeks after receiving the last dose of the COVID-19 vaccine.
(For now, the last dose is the second dose of the Pfizer or Modern versions. When the Johnson & Johnson single dose vaccine goes into operation, as expected after federal approval later this month, the first dose will also be the last dose , Parkinson noted.)
Parkinson emphasized that if a patient has other symptoms of breast cancer – a lump in the breast, or bloody discharge from the nipple, or flaking around the nipple – she should not hesitate to consult her doctor. “We will go ahead and do the mammogram,” said Parkinson.
When mammography is routine, such as an annual checkup or follow-up exam after a mastectomy, the test can be postponed, but not indefinitely, said Parkinson.
“Don’t skip your annual screening mammogram,” said Parkinson. “Postponing for a month or two will not have as much impact. Postponing for a year can really be. “
Women at medium risk for breast cancer should have a screening mammogram at age 40, and every year thereafter, as long as they are healthy, Parkinson said. Women with a family history of breast cancer, such as a mother or sister, should start having mammograms at 40 or 10 years old before the age their relative was diagnosed, whichever comes first, he said.
Parkinson said the Breast Treatment Center does not provide screening mammograms for men, who account for less than 1% of all breast cancer cases. If a man finds a palpable lump, though, he should have a diagnostic mammogram, said Parkinson.