title: 11C-Methionine-PET in Multiple Myeloma: Correlation with Clinical Parameters and Bone Marrow Involvement.
abstract: Multiple myeloma (MM) remains an essentially incurable hematologic malignancy originating from clonal plasma cells. This study evaluated the usefulness of the radiotracers (11)C-methionine (MET) and (18)F-2`-deoxy-2`-fluorodeoxyglucose (FDG) for staging and re-staging in MM. 43 patients with MM underwent both MET- and FDG-PET/CT for staging or re-staging within 3±2 days. Scans were compared on a patient and on a lesion basis. Tracer uptake was correlated with the degree of bone marrow (BM) involvement and standard clinical parameters of disease activity. Additionally, BM samples were stained for L-type amino acid transporter 1 (LAT1) expression in 15 patients. MET-PET detected focal lesions (FL) in 39/43 subjects (90.7%), whereas 10 patients were missed in FDG-PET/CT (detection rate, 33/43; 76.7%; p<0.05). MET depicted more FL in 28/43 patients (65.1%; p<0.001), whereas in the remainder (34.9%, n=15) both tracers yielded comparable results. LAT1 was highly expressed on the cell surface of myeloma cells. Both FDG and MET uptake correlated significantly with biopsy-proven BM involvement (p<0.001), with MET demonstrating a stronger correlation (SUVmean, r=0.9 vs r=0.6; SUVmax, r=0.88 vs r=0.58). Abnormal beta-2-microglobulin and free light chain levels correlated with the presence of focal intramedullary lesions detected in MET- or FDG-PET/CT (MET, p=0.006 and p=0.01, respectively; FDG, p=0.02 and p=0.01). MET appears to be superior to FDG for staging and re-staging of both intra- and extramedullary MM lesions. Tracer uptake correlates with BM involvement, β2m and FLC levels and appears to be a more accurate marker of tumor burden and disease activity.
authors.affiliation: 1. University Hospital Würzburg, Department of Nuclear Medicine, Würzburg, Germany; 4. Comprehensive Cancer Center Mainfranken, Würzburg, Germany.
authors.forename: Constantin
authors.initials: C
authors.lastname: Lapa
authors.affiliation: 2. University Hospital Würzburg, Department of Hematology and Oncology, Würzburg, Germany; 4. Comprehensive Cancer Center Mainfranken, Würzburg, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Knop
authors.affiliation: 2. University Hospital Würzburg, Department of Hematology and Oncology, Würzburg, Germany; 4. Comprehensive Cancer Center Mainfranken, Würzburg, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Schreder
authors.affiliation: 3. Institute for Pathology, University of Würzburg, Würzburg, Germany; 4. Comprehensive Cancer Center Mainfranken, Würzburg, Germany.
authors.forename: Martina
authors.initials: M
authors.lastname: Rudelius
authors.affiliation: 2. University Hospital Würzburg, Department of Hematology and Oncology, Würzburg, Germany; 4. Comprehensive Cancer Center Mainfranken, Würzburg, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Knott
authors.affiliation: 1. University Hospital Würzburg, Department of Nuclear Medicine, Würzburg, Germany; 4. Comprehensive Cancer Center Mainfranken, Würzburg, Germany.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Jörg
authors.affiliation: 1. University Hospital Würzburg, Department of Nuclear Medicine, Würzburg, Germany; 4. Comprehensive Cancer Center Mainfranken, Würzburg, Germany.
authors.forename: Samuel
authors.initials: S
authors.lastname: Samnick
authors.affiliation: 1. University Hospital Würzburg, Department of Nuclear Medicine, Würzburg, Germany; 4. Comprehensive Cancer Center Mainfranken, Würzburg, Germany.
authors.forename: Ken
authors.initials: K
authors.lastname: Herrmann
authors.affiliation: 1. University Hospital Würzburg, Department of Nuclear Medicine, Würzburg, Germany; 4. Comprehensive Cancer Center Mainfranken, Würzburg, Germany.
authors.forename: Andreas K
authors.initials: AK
authors.lastname: Buck
authors.affiliation: 2. University Hospital Würzburg, Department of Hematology and Oncology, Würzburg, Germany; 4. Comprehensive Cancer Center Mainfranken, Würzburg, Germany.
authors.forename: Hermann
authors.initials: H
authors.lastname: Einsele
authors.affiliation: 1. University Hospital Würzburg, Department of Nuclear Medicine, Würzburg, Germany; 4. Comprehensive Cancer Center Mainfranken, Würzburg, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Lückerath
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001853:Bone Marrow / Q000378:metabolism / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008715:Methionine; D008875:Middle Aged; D064847:Multimodal Imaging; D009101:Multiple Myeloma / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D014057:Tomography, X-Ray Computed
chemical_list: D014408:Biomarkers, Tumor; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; C086242:carbon-11 methionine; D008715:Methionine
keywords: 11C-methionine; FDG; PET/CT; multiple myeloma