Prognostic value of pretransplantation positron emission tomography using fluorine 18-fluorodeoxyglucose in patients with aggressive lymphoma treated with high-dose chemotherapy and stem cell transplantation.

The study assessed the prognostic value of fluorine 18-fluorodeoxyglucose positron emission tomography ([18F]FDG-PET) after salvage chemotherapy before high-dose chemotherapy with stem cell transplantation (HDT/SCT) in patients with induction failure or relapsing chemosensitive lymphoma. Retrospective analysis of the clinical and conventional imaging data of 60 patients scheduled for HDT/SCT was performed in parallel with the analysis of the [18F]FDG-PET results. To determine the ability of [18F]FDG-PET to predict clinical outcome, PET images were reread without knowledge of conventional imaging and clinical history. Presence or absence of abnormal [18F]FDG uptake was related to progression-free survival (PFS) and overall survival (OS) using Kaplan-Meier survival analysis. Thirty patients showed a negative [18F]FDG-PET scan before HDT/SCT; 25 of those remained in complete remission, with a median follow-up of 1510 days. Two patients died due to a treatment-related mortality but without evidence of recurrent disease at that time (228-462 days). Only 3 patients had a relapse (median PFS, 1083 days) after a negative [18F]FDG-PET scan. Persistent abnormal [18F]FDG uptake was seen in 30 patients and 26 progressed (median PFS, 402 days); of these 26, 16 died from progressive disease (median OS, 408 days). Four patients are still in complete remission after a positive scan. Comparison between groups indicated a statistically significant association between [18F]FDG-PET findings and PFS (P <.000001) and OS (P <.00002). [18F]FDG-PET has an important prognostic role in the pretransplantation evaluation of patients with lymphoma and enlarges the concept of chemosensitivity used to select patients for HDT/SCT.