Chondromyxoid fibroma of the rib mimics a chondrosarcoma on 18F-FDG PET/CT.

Chondromyxoid fibroma (CMF) is a rare benign bone tumor of chondroid origin that occurs mostly in the metaphyses of long bones. CMF can occasionally mimic a chondrosarcoma on CT, and the literature on the 18F-FDG PET/CT imaging characteristics of CMF tumors is limited. In the presented case, a large histologically proven CMF chest wall mass was initially misinterpreted as a chondrosarcoma. This case highlights a potential pitfall in the PET/CT evaluation of these rare benign bone tumors.