Lymphadenopathy related to COVID-19 vaccination should not delay mammography
Click Here to Manage Email Alerts
The resolution of lymphadenopathy caused by COVID-19 vaccination takes longer than initially suspected, findings showed, but researchers stressed that mammography should not be delayed.
The prolonged resolution time — compared with what was originally reported in vaccine clinical trials — means that physicians should consider a follow-up interval of at least 12 weeks for suspected vaccine-related lymphadenopathy.
“After the initial COVID-19 vaccine roll-out, our breast imaging team noticed several patients presenting with enlarged axillary lymph nodes,” Michele B. Drotman, MD, chief of the division of breast imaging and an associate professor of clinical radiology at Weill Cornell Medical College, told Healio.
Isolated enlarged axillary lymph nodes were previously an uncommon finding, according to Drotman.
“Initial guidelines suggested sonographic imaging follow-up of 4 to 12 weeks to resolution, however, we were prompted to undertake this study to further clarify the duration of lymph node enlargement in these select patients,” Drotman added.
The researchers analyzed the medical records of 111 patients who received a Pfizer-BioNTech or Moderna vaccine within 8 weeks before having a breast ultrasound that revealed unilateral axillary lymphadenopathy ipsilateral to where their vaccine was administered. Ultrasounds were performed between Jan. 1, 2021, and Oct. 1, 2021, with follow-up ultrasounds performed at intervals of 4 to 12 weeks until the cortical thickness of the largest axillary lymph node was 3 mm or smaller.
At the initial ultrasound, the mean cortical thickness was 4.7 mm ± 1.2 mm. Lymph nodes returned to a normal size at a mean of 97 ± 44 days after the first ultrasound, at a mean of 127 ± 43 days after patients’ first dose and after a mean of 2.4 ± 0.6 follow-up ultrasounds.
Lymphadenopathy resolved more quickly in women who received the Pfizer-BioNTech vaccine vs. the Moderna vaccine, researchers said (beta coefficient, –18; 95% CI, –34.3 to –1.7). Receiving a second dose after the initial ultrasound (beta coefficient, 19.2; 95% CI, 3.1-35.2) and greater initial cortical thickness (beta coefficient, 8; 95% CI, 1.5-14.5) were significant predictors of longer time to resolution.
“Our findings support the current recommendations to not delay screening mammography due to timing with COVID-19 vaccine,” Drotman said. “In addition, if enlarged lymph nodes are identified, these can be followed at longer, less frequent intervals.”
Drotman said her team is investigating whether there is a similar immune response following the administration of booster doses. They are also interested in studying “the effect of other more traditional vaccines that can also enlarge lymph nodes, but perhaps not as dramatically,” she said.