Prognostic value of interim and end-of-treatment 18F-FDG PET/CT responses based on the Deauville five-point score in peripheral T-cell lymphoma: a systematic review and meta-analysis

Studies on interim and end-of-treatment Deauville five-point score (D5PS)-based 18 F-fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) responses in patients with peripheral T-cell lymphoma (PTCL) were comprehensively reviewed. English-language articles were identified through searches of PubMed, EMBASE, and the Cochrane Library. The prognostic significance of interim and end-of-treatment 18 F-FDG PET/CT responses, based on D5PS, was analyzed using pooled hazard ratios (HRs). In total, 9 studies involving 851 patients with PTCL were included in this study. Patients with higher interim and end-of-treatment 18 F-FDG PET/CT response scores showed an association with worse progression-free survival (PFS), with pooled HRs of 2.83 (95% confidence interval [CI] = 1.85–4.33, I 2 = 67.2%; P = 0.001) and 4.20 (95% CI = 1.75–10.11, I 2 = 77.9%; P = 0.001), respectively. In addition, higher interim and end-of-treatment 18 F-FDG PET/CT response scores were also associated with worse overall survival (OS), with pooled HRs of 3.12 (95% CI = 1.83–5.34, I 2 = 73.6%; P < 0.001) and 8.26 (95% CI = 3.43–19.91, I 2 = 75.6%; P = 0.003), respectively.Subgroup analysis indicated that the PFS HR of the univariate analysis group was 2.67 (95% CI = 1.35–5.29, I2 = 16.4%; P = 0.274), and the OS HR of the Asian group was 14.23 (95% CI = 5.80–34.93, I2 = 0.0%; P = 0.508), without significant between-study heterogeneity. Although various strategies have been used for different PTCL types, interim and end-of-treatment 18 F-FDG PET/CT responses were identified as significant predictors of PTCL prognosis. Nevertheless, large prospective studies are required to confirm the prognostic value of PET/CT parameters in patients with PTCL.