F-18 FDG PET/CT staging of multiple myeloma with diffuse osseous and extramedullary lesions.

Multiple myeloma is the most common plasma cell neoplasm, with abnormal clonal proliferation of B cells in bone marrow. Its staging is important for therapeutic management and prognosis. F-18 FDG PET/CT is of proven value in staging and posttherapeutic monitoring multiple myeloma. Through imaging integration, PET provides functional detection of high metabolic lesions whereas CT provides correlated anatomic localization. The authors present a case of multiple myeloma status post chemotherapy and stem cell transplant with diffuse osseous and extramedullary lesions evaluated by PET/CT. The extramedullary involvement concerns the maxillary sinus, thyroid cartilage, mediastinum, retroperitoneum, neuroforamen, and epidura.