Deciphering the Role of Fluorodeoxyglucose-Positron Emission Tomography/CT Imaging in the Management of Sarcoidosis.

Abstract

2-Deoxy-2-[¹⁸F]fluoro-d-glucose (FDG)-PET/CT imaging has utility in identifying sites of active sarcoidosis. However, the role of FDG-PET/CT imaging in predicting treatment response and guiding therapy outside of cardiac disease is yet to be completely understood. Do physicians agree on the utility of FDG-PET/CT imaging in sarcoid cases, and do they agree on the appropriate treatment response, based on the associated reports? Physician respondents were presented with a series of anonymized sarcoidosis case vignettes. The perceived utility of FDG-PET/CT imaging in each case, as well as the ultimate treatment decision following provision of FDG-PET/CT results, was assessed. Interrater agreement was assessed overall and per-case vignette specialty, using the Gwet agreement coefficient (AC1). Respondents (n = 215) were predominantly respiratory physicians (86.78%) experienced in sarcoidosis management (94.39%), and one-third of whom had > 20 years of experience (32.66%). Pulmonary sarcoidosis case vignettes had the lowest rates of FDG-PET/CT endorsement among surveyed subspecialties (38%-64%). Overall interrater agreement was assessed among physicians who positively endorsed FDG-PET/CT imaging. Treatment rationalization based on FDG-PET/CT report approached near-chance agreement for pulmonary cases (AC1 = 0.178) (n = 217; 95% CI, 0.125-0.234; P = .07) and multisystem cases (AC1 = 0.296) (n = 168; 95% CI, 0.066-0.477; P = .41), whereas agreement was highest for cases of cardiac sarcoidosis (AC1 = 0.797) (n = 374; 95% CI, 0.759-0.838; P < .05). Our results indicate low agreement between physicians regarding their management of pulmonary sarcoidosis following FDG-PET/CT imaging. This highlights a need for further research and clarity concerning the role of FDG-PET/CT imaging in the therapeutic management of pulmonary sarcoidosis.