Radiation-Induced Giant Cell Granuloma Mimicking Relapsed Hodgkin Lymphoma at FDG-PET/CT.

A 22-year-old woman was diagnosed with intermediate risk stage II Hodgkin lymphoma and treated with three cycles of adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD) followed by involved-field radiation therapy. A complete metabolic remission was achieved after two cycles of ABVD, which was maintained until three years after completion of treatment. Follow-up FDG-PET/CT four years after completion of treatment, however, showed a new FDG-avid (Deauville score of 4) lesion in the right scapula, suggesting relapsed disease. Computer tomography (CT)-guided biopsy of this lesion was performed and subsequent histological examination revealed a radiation-induced giant cell granuloma.