carbon-11-acetate and Multiple-Myeloma

A 67-year-old man with newly diagnosed multiple myeloma underwent both FDG and C-acetate PET/CT sequentially on different days. There was increased FDG activity only in L1 vertebral body, but there was diffuse abnormal C-acetate activity throughout the skeletal system. After the successful therapy, the patient who was on remission clinically underwent follow-up PET/CT scans. Interestingly, L1 remained to have elevated FDG, although with less intensity. In contrast, there was no abnormal C-acetate activity anywhere in the body. The patient remained in remission clinically.

Topics: Acetates; Carbon; Humans; Male; Multiple Myeloma; Positron Emission Tomography Computed Tomography; Treatment Outcome

We prospectively compared (11)C-acetate with (18)F-FDG in a PET/CT evaluation of multiple myeloma (MM), specifically on diagnostic accuracy, identification of high-risk patients, and monitoring of treatment response.. Dual-tracer PET/CT was performed on 35 pathologically and clinically confirmed and untreated patients (26 with symptomatic MM, 5 with smoldering MM, and 4 with monoclonal gammopathy of unknown significance) and 20 individuals with normal marrow.. (11)C-acetate showed significant incremental value over (18)F-FDG (84.6% vs. 57.7%) for positively identifying patients with diffuse and focal symptomatic MM, and was negative in patients with indolent smoldering MM and monoclonal gammopathy of unknown significance. Three functional parameters-number of (11)C-acetate-avid and (18)F-FDG-avid focal bone lesions and (11)C-acetate general marrow activity-strongly correlated with β-2-microglobulin as surrogate imaging markers of tumor burden. After induction chemotherapy, the metabolic change in (11)C-acetate general marrow activity correlated with clinical response.. Metabolic characterization of MM in diagnosis, risk stratification, and treatment monitoring can be done more accurately by assessing lipid metabolism with (11)C-acetate than by assessing glucose metabolism with (18)F-FDG.

Topics: Acetates; Adult; Aged; Aged, 80 and over; Carbon; Case-Control Studies; Female; Fluorodeoxyglucose F18; Glucose; Humans; Lipid Metabolism; Male; Middle Aged; Multimodal Imaging; Multiple Myeloma; Paraproteinemias; Positron-Emission Tomography; Prospective Studies; Radiopharmaceuticals; Reproducibility of Results; Risk; Sensitivity and Specificity; Tomography, X-Ray Computed; Treatment Outcome; Tumor Burden

Multiple myeloma is a malignancy of plasma cells. The (18)F-FDG PET findings of multiple myeloma have been reported previously. However, the (11)C-acetate PET findings have not been clarified. Here, we report a case of multiple myeloma detected with (11)C-acetate PET in a 51-year-old male patient with known hepatocellular carcinoma. The patient was admitted for management of a pathologic fracture of the right tibia. Imaging workup including X-ray, magnetic resonance image, bone scintigraphy; (18)F-FDG led to a suspicion of metastatic bony lesions. Further, these lesions showed increased uptake on (11)C-acetate PET. Wide excision of the right tibia was performed, and histopathological examination of the lesion confirmed multiple myeloma. This case illustrates the characteristic (11)C-acetate PET findings of multiple myeloma.

Topics: Acetates; Bone and Bones; Carbon; Humans; Incidental Findings; Male; Middle Aged; Multiple Myeloma; Positron-Emission Tomography