Researchers warn About Post COVID 19 Vaccine Impact on Imaging

In another case series, Dr Can özütemiz and his team have reported about five cases of axillary lymphadenopathy which occurred after COVID-19 vaccination and that mimicked metastasis in oncologic patients. Initially, the researchers diagnosed the patients with metastasis. However, upon further investigation, they found that the patients received COVID-19 vaccinations in the ipsilateral arm prior to imaging. (2)

The details of the 5 case reports include:

Case 1: A 32-year-old female presented with a left-sided neck mass. Sonography revealed an indeterminant left intraparotid mass. She had a biopsy, staging PET/CT, and started chemotherapy; a three-month PET/CT follow-up showed that the mass had resolved. However, PET/CT revealed multiple new, mildly enlarged, and hypermetabolic left axillary lymph nodes with fat stranding. Initially, the physicians diagnosed it as progression vs pseudoprogression secondary to immunotherapy. However, further investigation revealed that the patient received the second dose of Pfizer-BioNTech COVID-19 vaccine six days prior to PET/CT and there was triangular intramuscular FDG uptake in the left arm at the injection site.

Case 2: A 57-year-old female with a strong family history of breast cancer was undergoing an annual MRI for high-risk breast cancer screening. The most recent contrast-enhanced breast MRI showed increasing size and number of unilateral left axillary lymph nodes, concerning malignancy. However, upon further investigation, the radiologists found that the patient had received her second dose of Pfizer-BioNTech COVID-19 vaccine five days before the breast MRI.

Case 3: A 41-year-old man with a history of liposarcoma in the left thigh had previously undergone pre-operative radiotherapy, followed by surgical resection. Follow-up MRI showed new clusters of swollen lymph nodes; This appearance was similar to muscle abnormalities described above in Case 1. Upon discussion with the patient, the radiologists confirmed that the patient received the second dose of the Pfizer-BioNTech COVID-19 vaccine four days prior to the exam.

Case 4: A 46-year-old female with a history of triple-negative, poorly differentiated infiltrating ductal carcinoma of the left breast was treated with a double mastectomy. Follow-up chest CT showed swollen lymph nodes. The radiologist initially reported the PET/CT as “concerning for metastasis.” Later, they found that the patient received the first dose of Pfizer-BioNTech COVID-19 vaccine 15 days prior to the chest CT and the second dose, seven days prior to the PET/CT.

Case 5: A 38-year-old female, with a family history of breast cancer, was evaluated for the left breast and left axillary pain with a baseline diagnostic mammogram and ultrasound. Ultrasound showed a swollen lymph node; she underwent ultrasound-guided biopsy. Upon retrospective chart review the clinicians found that the patient had received the first dose of Pfizer-BioNTech COVID-19 vaccine in the left arm eight days before the initial mammogram, and the second dose on the day of the biopsy.

Dr Can Özütemiz and his team concluded, “Reactive axillary lymphadenopathy following COVID-19 vaccination may mimic metastasis. Therefore, radiologist/clinicians should question recent history of COVID-19 vaccination in cases of unilateral axillary lymphadenopathy.”