A 56-year-old woman with high-grade neuroendocrine small cell carcinoma had known contact history of COVID-19 about 16 days prior to the restaging PET/CT. The patient was instructed to self-quarantine for 14 days, and no COVID-19 test was performed. Upon arrival, the patient had low-grade fever of 37.1°C, but did not meet infection control criteria for COVID-19 testing, and it was approved to proceed with PET/CT. The FDG PET/CT images revealed new multifocal hypermetabolic bilateral pulmonary ground-glass opacities that are suggestive of COVID-19 pneumonia. Meanwhile, the patient's symptoms worsened, and a blood test later confirmed COVID-19 infection.