FDG-PET/CT findings highly suspicious for COVID-19 in an Italian case series of asymptomatic patients

Abstract

Aim: To illustrate the [18F]FDG-PET/CT findings in patients affected by cancer with clinical diagnosis of Covid-19 METHODS: We retrospectively reviewed the cases of patients who showed pulmonary involvement unrelated to cancer metastases on March 13 and 16 2020. We reviewed the scans, collected medical history, and exposure information.

Results: Among the 13 scans, we identified 5 cases with imaging findings suspicious for viral infection. Peripheral lung consolidations and/or ground-glass opacities in two or more lobes were found. Lung abnormalities displayed increased [18F]FDG uptake (SUVmax 4.3-11.3). All the patients on the day of PET/CT acquisition were asymptomatic, and they did not have fever or cough. In view of the PET/CT findings, home isolation, symptom surveillance, and treatment (in 3/5 patients) were indicated. At 1-week follow-up, 2/5 patients experienced the onset of mild respiratory symptoms.

Conclusions: The [18F]FDG-PET/CT can identify probable Covid-19 disease in the absence or before symptoms onset and can guide patient management. Nuclear medicine staff needs to be aware of the possibility of contact with patients affected by the SARS-CoV-2 infection even if they do not present any symptom. Therefore, safety measures need to be adopted for other patients and hospital staff in order to block the spread of infection.

Keywords: Asymptomatic; COVID-19; Coronavirus; FDG-PET/CT; Imaging; SARS-CoV-2.

Fig. 1

PET/CT (axial CT—panel a; axial fused PET/CT—panel b) showed multiple bilateral interstitial infiltrates (right upper, middle and lower, and left upper and lower lobes—orange arrows) with increased [18F]FDG uptake (SUVmax 4.3)

Fig. 2

PET/CT (axial CT—panel a; axial fused PET/CT—panel b) showed bilateral ground glass opacities (right lower and left upper and lower lobes—orange arrows), especially in the left 100 lung, with increased [18F]FDG uptake (SUVmax 4.3)

Fig. 3

On the scan (axial fused PET/CT—panel a; axial PET—panel b; sagittal fused PET/CT—panel c; coronal fused PET/CT—panel d) increased [18F]FDG uptake (SUVmax 11.3) was visible on the lung opacities of the right upper (orange arrows) and modest uptake in the lower lobes

Fig. 4

The [18F]FDG-PET/CT CT (axial CT—panel a; axial fused PET/CT—panel b) showed bilateral subpleural ground glass opacities (right upper and lower and left lower lobes) with focally increased [18F]FDG uptake (SUVmax 5.3) (orange arrows)

Fig. 5

PET/CT (axial CT—panel a; axial fused PET/CT—panel b) showed lung ground-glass opacities in the right upper, middle, lower lobe, and left inferior lobe (SUVmax 4.9) (orange arrows)