[Prognostic Value of Interim PET/CT in 227 Patients of DLBCL].

Objective: To investigate the prognostic evaluation value of fluorodeoxyglucose (FDG) interim positron emission tomography/computed tomography (PET/CT) for diffuse large B cell lymphoma (DLBCL).

Methods: Two hundred and twenty-seven patients with pathologically diagnosed DLBCL underwent 18F-FDG scans at baseline and before 3 cycles of a rituximab-containing chemotherapy regimen. The Visual Deauville score (DS) and changes in maximum standard uptake values (ΔSUVmax) were calculated for tracer for the predominant lesion of each patient, for prediction of progression-free survival (PFS) and overall survival (OS) using Kaplan-Meier method and COX regression.

Results: The median follow-up period was 71 months. Receiver operating characteristic analysis indicated that the best ΔSUV cut-off values for FDG (ΔSUVFDG) was 71%. The sensitivity, specificity and accuracy of DS and ΔSUVmax were 86.9%, 74.3%, 82.8% and 77.8%, 63.5%, 73.1%, respectively in response assessment. Kaplan-Meier analysis showed DS, ΔSUVmax and IPI had significance for prediction of PFS and OS (P = 0.001). The DS 4-5 and IPI 3-5 were independent risk factors of poor prognosis by COX regression analysis.

Conclusion: Interim PET/CT is important predictor for evaluation therapeutic response and prognosis in DLBCL patients.