A 9-year-old boy underwent baseline 18 F-fluorodeoxyglucose (FDG) Positron Emission Tomography/Computed Tomography (PET/CT) for staging of B-cell Hodgkin lymphoma, which revealed a moderately hypermetabolic mediastinal lymph node mass and unexpectedly intense, diffuse, and symmetric FDG uptake in subcutaneous and visceral white adipose tissue. The patient was receiving a tapering corticosteroid regimen (60 mg to 20 mg over one month), which likely accounted for this metabolic activation. Two months later, follow-up PET/CT after chemotherapy showed complete resolution of both the mediastinal uptake and the diffuse adipose hypermetabolism, confirming the steroid-related origin of the initial finding. Such steroid-induced adipose hypermetabolism can mimic or obscure disease-related lesions, potentially leading to staging inaccuracies. Awareness of this pitfall is essential for accurate image interpretation, and repeating FDG PET/CT after corticosteroid discontinuation is strongly recommended to ensure reliable differentiation between pharmacologic effects and true pathological uptake.
Alami et al. (2026) studied this question.