Multiorgan Involvement of Chemotherapy-Induced Sarcoidosis Mimicking Progression of Lymphoma on FDG PET/CT.

A 35-year-old woman with biopsy-proven recurrent Hodgkin lymphoma in the neck lymph nodes received salvage chemotherapy of brentuximab/insulin growth factor-methotrexate. Although the patient continued doing well clinically with no constitutional symptoms or significant laboratory abnormalities following the second recurrence, subsequent FDG PET CT examinations over the next 2 years revealed multiple new FDG-avid foci including lymph nodes above/below the diaphragm, liver, spleen, lungs, and bone. An alternate diagnosis of chemotherapy-induced sarcoidosis was suggested and confirmed on both bone marrow and right inguinal node biopsy.