Usual and unusual pitfalls of 18F-FDG-PET/CT in lymphoma after treatment: a pictorial review.

Fluorine-18-fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) is now a standard of care in initial staging and treatment evaluation of lymphomas. It is also used in the interim evaluation in diffuse large B cell lymphoma and Hodgkin lymphoma. However, several pitfalls may occur during or after treatment, because of the nonspecificity of F-FDG for lymphoma disease and treatment as immunotherapy, thus possibly induces misinterpretation and wrong treatment decision.

Chemotherapy-related gallbladder visualization in a 99mTc-HMDP SPECT/CT bone scan.

Nonosseous uptakes are occasionally found on bone scintigraphy. Most of them are easily explained by current pathophysiological mechanisms (metastatic calcifications, metabolic process, or extravascular accumulation of radiopharmaceutical) or current artifacts. Other unusual findings are still unexplained.