Erica Leigh Martin-Macintosh MD, Presenter: Nothing to Disclose

Geoffrey Bates Johnson MD, PhD, Abstract Co-Author: Nothing to Disclose

Benjamin Matthew Howe MD, Abstract Co-Author: Nothing to Disclose

Christopher Harker Hunt MD, Abstract Co-Author: Nothing to Disclose

Patrick James Peller MD, Abstract Co-Author: Nothing to Disclose

Durie-Salmon score (DSS), international staging system (ISS), and genetic characterization via fluorescence in-situ hybridization (FISH) using the Mayo Stratification for Myeloma And Risk-adapted Therapy (mSMART) offer prognostic stratification in newly diagnosed multiple myeloma. The extent of bone lesions seen on 18F-FDG PET/CT is also known to predict patient outcomes. However it is unclear if volumetric parameters of metabolic disease seen on PET/CT correlate with clinical risk stratification.

Patients with newly diagnosed multiple myeloma who had undergone pretreatment 18F-FDG PET/CT and genetic analysis were reviewed retrospectively. Multiple PET/CT parameters were evaluated including mean and maximum standardized uptake values (SUVmean, SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) using MIRADA volume viewer software. The significance of these metabolic parameters and the general PET/CT disease appearance (focal plasmacytomas versus diffuse disease) were then compared to the clinical myeloma risk stratification and laboratory variables. Statistical analysis was performed with JMP software.

Thirty-one patients with a mean age of 59 ± 12 years were reviewed. Multiple patients were identified in each stage based on DSS and ISS and in each genetic risk group of mSMART. FISH detected 22 specific mutations. Neither DSS, ISS, nor mSMART correlated with volumetric PET/CT parameters. Several specific mutations correlated with the PET/CT appearance. Multiple focal plasmacytomas were seen with p53 (n=4), t(11:14) mutations (n=6), and hyperdiploidy (n=7). Diffuse bone marrow activity was seen with t(4:14) mutations (n=2). MTV of 440 ±855 cm3 correlated with serum LDH 201 ± 128 U/L (P<0.0001) and B2 microglobulin 4.79 ± 4.96 mg/L (P=0.049) levels.

The presence of plasmacytomas is more common in patients with specific mutations and hyperdiploidy. Metabolic volume of myeloma identified by PET/CT correlates with serum LDH level. The lack of relationship between high-risk genetic markers and metabolic disease volume and intensity suggests quantitative FDG uptake may be a risk factor independent from the established staging systems.

Quantitative PET/CT FDG uptake in newly diagnosed multiple myeloma appears to be a risk factor independent from the established staging and risk stratification systems.

Martin-Macintosh, E, Johnson, G, Howe, B, Hunt, C, Peller, P, Correlation of Pretreatment 18F-FDG PET/CT Metabolic Volumetric Analysis to Clinical Staging and Genetic Risk Parameters in Patients with Multiple Myeloma.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12034612.html