[18F]FDG PET-CT in patients with DLBCL treated with CAR-T cell therapy: a practical approach of reporting pre- and post-treatment studies

Abstract

Purpose: The introduction of CD19-speci c chimeric antigen receptor T-cell therapy (CAR-T) for treatment of relapsed/refractory diffuse large B cell lymphoma (R/R DLBCL) gives hope to patients with otherwise dismal prognosis. Therapy outcomes depend, however, on selection of patients and on accurate early identi cation of non-responders. Patients treated with CAR-T usually undergo [ 18 F]FDG PET-CT at time of decision (TD), time of CAR-T transfusion (TT), one month (M1) and three months (M3) post therapy. The purpose of the current study was to identify the speci c parameters that should be addressed when reporting PET-CT studies in the clinical setting of CAR-T therapy.Methods: A total of 138 PET-CT scans (30 TD, 42 TT, 44 M1, 22 M3) of 48 patients treated with CAR-T were included. SUVmax, TMTV, TLG were calculated in all scans. Response was assessed using Deauville scale and ΔSUVmax method. Overall survival (OS) was the primary endpoint. Median follow-up was 12.8 (IQR 6.4-16.0) months from CAR-T infusion.Results: In a univariate analysis, TD-SUVmax > 17.1 and TT-SUVmax > 12.1 were associated with shorter OS (Pv<0.05). In a multivariate analysis, three factors were signi cantly associated with shorter OS: TD-

Early Hyperprogression of Lymphoma Detected by 18F-FDG PET/CT After Chimeric Antigen Receptor T-Cell Therapy

“…4 The usefulness of 18 F-FDG PET/CT in predicting the efficacy of CAR-T therapy in refractory non-Hodgkin lymphoma has been demonstrated. [5][6][7][8][9] Pseudoprogression detected by 18 F-FDG PET/CT after CAR-T therapy has also been reported. However, the findings of hyperprogression on 18 F-FDG PET/CT are rarely reported.…”

“…Reported hyperprogression incidence on checkpoint inhibitors varied between 2.5% and 29.4% of all responses 4 . The usefulness of 18 F-FDG PET/CT in predicting the efficacy of CAR-T therapy in refractory non-Hodgkin lymphoma has been demonstrated 5–9 . Pseudoprogression detected by 18 F-FDG PET/CT after CAR-T therapy has also been reported.…”

Positron emission tomography-imaging assessment for guiding strategy in patients with relapsed/refractory large B-cell lymphoma receiving CAR T cells

“…It has been shown in ZUMA-1 and JULIET trials that reaching complete metabolic response (CMR) or partial metabolic response (PMR) according to Lugano criteria three months after infusion is predictive of sustained response and had similar outcome 1,3 . Although the median time to response is around one month in pivotal trials and real-world experiences 1,2,4,7 , the prognostic value of PET assessment after CAR T-cells infusion is under investigation 10 , and the conversion rate of response from one month to three months post CAR T-cells not fully documented.…”

Whole body FDG PET/MR for progression free and overall survival prediction in patients with relapsed/refractory large B-cell lymphomas undergoing CAR T-cell therapy

“…A lower tumor burden and/or lower tumor FDG uptake have been linked to better outcomes. An early metabolic response after treatment has also proved predictive of therapy success, assessed visually [ 13 , 16 ] or semi-quantitatively using SUV max [ 12 , 13 , 15 ]. In general, the studies performed are however small and mixed results have been reported in terms of which predictive metric to use.…”

“…In addition, FDG PET/CT is a promising tool for identifying responding/non-responding patients after CAR T-cell therapy. In patients with LBCL undergoing CAR T-cell therapy, usage of pre-therapy FDG PET tumor metrics such as the Metabolic Tumor Volume (MTV), Total Lesion Glycolysis (TLG) and maximum Standardized Uptake Value (SUV max ) have been associated with treatment outcome [10][11][12][13][14][15]. A lower tumor burden and/or lower tumor FDG uptake have been linked to better outcomes.…”