PET/CT in benign and malignant musculoskeletal tumors and tumor-like conditions.

This article briefly reviews malignant bone tumors, diffuse marrow infiltrating diseases, and other benign bone diseases with fluorodeoxyglucose (FDG) uptake on positron emission tomography/computed tomography (PET/CT) that should be differentiated from malignant tumors. Clinical use of FDG PET/CT in (1) primary malignant bone tumors including osteosarcoma, malignant fibrous histiocytoma, and primary bone lymphoma, (2) hematopoietic tumors with bone marrow involvement, such as plasmacytoma, multiple myeloma, lymphoma and leukemia, and (3) benign tumors and tumor-like lesions including hemangioma, neurogenic tumor, fibrous dysplasia, and nodular fasciitis are presented, with an emphasis on various imaging findings on FDG PET/CT. Benign tumors and tumor-like conditions are often incidentally detected on FDG PET/CT in serial follow-up studies of cancer patients and should be differentiated from metastasis.