FIGURE 4.

A 62-year-old man affected by follicular lymphoma underwent PET/CT scan for evaluating treatment response after 6 cycles of chemotherapy, and PET/CT showed a partial metabolic response with persistence of increased FDG uptake to an inguinal node (A–D) and the appearance of several bilateral lung consolidative and FDG-avid nodular areas, especially in the superior lobes with SUV_max of 9 (E–G). Being the pattern atypical for COVID-19, the patient started new chemotherapy regimen, but after the early onset of cough and dyspnea, RT-PCR test was done with positive finding for COVID-19. Chest radiographs and CT is the preferred examinations for screening, diagnosis, and monitoring of COVID-19 pneumonia.^1–3 In this setting, the role of ¹⁸F-FDG PET/CT is still unclear with only few cases present.^{4–10 18}F-FDG PET/CT is a noninvasive tool with a significant role in evaluating several phlogistic and infectious pulmonary diseases, such as sarcoidosis and tuberculosis.¹¹ However, usually lesions presenting as GGOs are unlikely to have FDG uptake.¹² In agreement with previous articles,^6–8 our patients were characterized by the presence of bilateral peripheral consolidative areas and/or GGOs. All had increased FDG uptake higher than blood pool activity. COVID-19 do not seem to be associated with lymph node involvement; however, Qin et al⁶ reported an increased nodal FDG uptake in 3 of 4 cases. Of course ¹⁸F-FDG PET/CT is not routinely recommended for pulmonary lung inflammatory diseases and not indicated in an emergency setting, but our findings underline that COVID-19 pneumonia are characterized by high ¹⁸F-FDG uptake in most cases despite GGOs appearance.