Assessment of Diffuse Large B-Cell Lymphoma Beyond Geometric Characterization

Abstract Introduction: Lugano classification and Deauville scoring system are used for staging of lymphoma. As Lugano staging system is concerned about geometric characterization as size and location of the lesions while Deauville score is concerned about lesions with the highest SUVmax readings; other metabolic biomarkers in FDG PET/CT studies such as Metabolic tumor volume (MTV) as well as Total lesion glycolysis (TLG) are measuring overall tumor metabolic activity and gives idea about the disease total active burden in the patient. In our study we aim to investigate and compare the different estimated varieties of metabolic activity within the same group staging as per Lugano and Deauville systems. Methods: on a random sample of 30 adult patients newly diagnosed with DLBC lymphoma, 18F-FDG PET/CT imaging was done for staging. The patients after then divided by using Lugano staging and Deauville scoring system. Numeric analysis of the FDG PET/CT findings was done including SUVs, MTV and TLG. Comparison was done of the estimated results within different groups. Results: Metabolic biomarkers were irrelevant to the disease staging according to Lugano and/or Deauville systems. Even within the same staging group we found wide variation of the numeric values of metabolic biomarkers which are reflecting wide variation of disease active condition. Discussion: Further efforts were needed to detect and measure the functionality of the disease and actual active tumor burden and aggressiveness of the disease beyond the geometric characterization; size, location, distribution …etc. In our study we found wide range of variation of MTV and TLG at the same stage as per Lugano and/or Deauville classification systems. Conclusion: Quantitative evaluation of the metabolic status of the disease is an independent factor referring to the actual aggressiveness of the disease and giving more detailed functional evaluation of the disease condition. Both MTV as well as TLG are reliable parameters at 18F-FDG PET/CT scans in DLBC Lymphoma referring to the whole-body active disease burden with wide variation of estimated numbers even within the same Lugano stage and/or Deauville scoring with different expected outcomes and course of disease.