Coexistence of physiologic and abnormal muscle uptake of fluorine-18-fluorodeoxyglucose in a patient with plasma cell leukemia.

Abstract

Fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) performed for restaging in a 70-year-old male patient with history of plasma cell leukemia (PCL) showed increased symmetrical and asymmetrical fluorine-18-fluorodeoxyglucose (FDG) uptake in some muscular groups. Magnetic resonance imaging showed structural abnormalities in the area of asymmetrical muscle uptake at FDG-PET/CT. Symmetrically increased FDG uptake was considered of functional significance. The pattern of muscle uptake at FDG-PET and the presence of concomitant abnormalities at the corresponding CT scan were useful to discriminate between physiological and abnormal findings in this patient with PCL (Figs. 1, ​,22 and ​and33). Fig. 1 A 70-year-old male patient previously treated for plasma cell leukemia (PCL), secondary to multiple myeloma, was referred to our institute because of the onset of low back pain radiating to the left leg and walking difficulties (the patient was on a wheelchair). ... Fig. 2 Axial CT (first column), PET (second column) and PET/CT (third column) showed multiple areas of symmetrically increased FDG uptake corresponding to several muscle groups (yellow arrows), without any significant abnormalities at the corresponding CT scan. ... Fig. 3 Axial PET (first row), CT (second row) and PET/CT (third row) images showed also the presence of an area of asymmetrical increased FDG uptake corresponding to the left gluteus medius muscle (red arrows), with a SUVmax of 7.9. CT scan demonstrated swelling ...