Prevalence of incidental pneumonia consistent with COVID19 infection an 18F-Fcholine (FCH) PET/CT in patients referred for prostate cancer

Aim/Introduction: COVID-19-induced lung lesions are already known to frequently take-up FDG, but such a finding has not yet been described with FCH, first line radiopharmaceutical in France for prostate cancer, that may be taken-up by inflammatory lesions Our aim was to evaluate the prevalence of incidental interstitial pneumonia consistent with COVID19 infection on CT and the FCH uptake of the lesions in patients referred to FCH PET/CT for prostate cancer Materials and Methods: We retrospectively reviewed all the PET/CTs of patients referred to FCH PET/ CT between 22nd February and 30th April 2020 for prostate cancer imaging They had no respiratory symptoms at the time of PET/CT We selected the cases showing lung lesions evocative of COVID-19 interstitial pneumonia on CT (ground-glass opacities, multifocal patchy consolidation, and interstitial changes with a peripheral distribution predominating in lower and posterior regions) and we determined the radiotracer uptake by these lesions Results: 96 FCH PET/CT were performed during this period of time We noticed lung lesions on CT consistent with COVID 19 infection in 4 of the 96 patients Median age of these patients was 72 5 years (range 68 to 76) All 4 patients were asymptomatic at the time of FCH PET/CT, but 2 of them reported a history of symptomatic pneumopathy compatible with COVID infectious syndrome, 4 weeks and 6 5 weeks before FCH PET/CT, respectively One of them had been sampled for RT-PCR when he was symptomatic and the diagnosis of Covid-19 infection was settled The lung lesions took-up FCH in all 4 patients with a mean SUVmax of 4 2 (range: 2 8 to 6 6) Ground-glass opacities were more hypermetabolic (SUVmax 6 6 and 3 9 respectively) and more diffuse (over more than 30% of pulmonary surface) in the 2 patients who had presented with symptomatic pneumonia Conclusion: During the COVID 19 outbreak in France, we incidentally observed hypermetabolic lung lesions consistent with COVID-19 infection in 4 1% of patients referred to FCH PET/CT for prostate cancer Patients with recurrent prostate cancer belong to a population at high risk of aggressive Covid-19 infection (male patients aged over 60) and the incidental discovery of pneumopathy evocative of COVID-19 on CT could be expected However, FCH uptake by the lung lesions was not expected in asymptomatic patients several weeks after the contamination Its prognostic significance (delayed recurrence? parenchymal fibrosis?) needs to be determined by patients' follow-up