Fig 6.

A 59-year-old woman with current metastatic squamous cell lung cancer (stage IV), status post chemotherapy and radiation, presented for routine surveillance ¹⁸F-fluorodeoxyglucose (FDG) PET/CT. The patient had received the second dose of the Pfizer-BioNTech coronavirus disease 2019 (COVID-19) vaccination in the left deltoid muscle 5 days before imaging. (A,B) Chest CT demonstrated new left axillary lymphadenopathy, (C,D) with moderate to intense uptake on FDG PET. (E) In the right middle lobe, at the site of primary malignancy, nodularity was identified along the area of radiation fibrosis. (F) There was interval progression of a right eighth posterolateral rib lytic metastasis (arrow). Given recent COVID-19 vaccination, the left axillary lymph nodes were assessed as likely reactive. Attention on follow-up studies was advised.