Assessment of Total Lesion Glycolysis and Metabolic Tumor Volume Improve the Clinical Value of Focal Lesion Assessment By FDG PET/CT in Myeloma

• Published in: Blood 2015-12, Vol.126 (23), p.724-724
• Main Authors: McDonald, James E, Kessler, Marcus M, Gardner, Michael, Buros, Amy, Waheed, Sarah, Ntambi, James, van Rhee, Frits, Zangari, Maurizio, Heuck, Christoph, Petty, Nathan, Schinke, Carolina, Thanendrarajan, Sharmilan, Mitchell, Alan, Hoering, Antje, Barlogie, Bart, Morgan, Gareth J, Davies, Faith E
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood.V126.23.724.724

Introduction: Focal lesions are important anatomical features seen in the bone marrow of multiple myeloma patients that contribute to drug resistance and disease relapse. Fluroine-18 fluorodexyglucose positron emission tomography with CT attenuation correction (18F-FDG PET/CT) is useful in the detection and enumeration of focal lesions and in semi-quantitative characterization of metabolic activity by calculation of glucose uptake reported as a standardized uptake value (SUV). Lesion count and SUV are predictors of outcome. Two additional variables, total lesion glycolysis (TLG) and metabolic tumor volume (MTV) can also be assessed and have the potential to improve the value of this approach. The purpose of this study was to determine whether TLG and MTV can predict progression free survival (PFS) and overall survival (OS), and to determine whether they are superior to traditional assessment methods. Materials and Methods: 191 patients underwent whole body PET/CT in the Total Therapy 3A trial and were evaluated using 3 dimensional region of interest analysis with TLG, MTV, and standard measurement parameters derived for all focal lesions with peak SUV above the background red marrow signal. Survival analysis was performed using Kaplan-Meier and log-rank tests. Univariate and multivariate analyses were performed using Cox proportional hazards regression. Results: Baseline characteristics show that 43/191 patients (23%) had no detectable lesions by PET. 1-3 lesions were present in 55/191 (28%) of patients and over 3 lesions in 93/191 (49%) of patients. A baseline TLG >205g was seen in 18% (34/191) of patients, with a TLG >620g being seen in 7% (14/191). A baseline MTV >210cm3 was seen in 7% (14/191). The distribution of patients with high TLG scores between molecular subgroups was not even with patients in the PR, MF and HY subgroups having higher scores. The 3 year PFS and OS for patients with no PET focal lesions was 83.1% and 88.3%, for patients with 1-3 lesions was 83.9%, and 85.5%, and for patients with >3 lesions 59.6% and 63.5% (p