Prognostic models for primary mediastinal (thymic) B-cell lymphoma derived from 18-FDG PET/CT quantitative parameters in the International Extranodal Lymphoma Study Group (IELSG) 26 study

The International Extranodal Lymphoma Study Group-26 study evaluated the prognostic role of 18-fluorodeoxyglucose positron-emission tomography (PET) in primary mediastinal large B-cell lymphoma. We assessed quantitative PET parameters at diagnosis and post-treatment in 100 patients. The end-of-therapy total lesion glycolysis (TLG) was the best individual outcome predictor, but the combination of baseline TLG and end-of-therapy visual analysis with Deauville Score (DS) showed a better positive predictive value. A model in which baseline TLG is combined with interim DS might identify patients with shorter progression-free survival. PET metrics combined with interim DS may allow early risk assessment and warrants further studies.