The role of baseline 18F-FDG PET/CT for survival prognosis in NSCLC patients undergoing immunotherapy: a systematic review and meta-analysis

Background: The value of pretreatment baseline 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET)/computed tomography (CT) as a prognostic factor for survival of patients with non-small-cell lung cancer (NSCLC) receiving immunotherapy remained uncertain. Objectives: To investigate the prognostic ability of baseline 18F-FDG PET/CT in patients with NSCLC receiving immunotherapy. Design: A systematic review and meta-analysis. Data sources and methods: We searched the PubMed, EMBASE, and Cochrane Central Register of Controlled Trials databases until May 7, 2024, and extracted data related to patient characteristics, semiquantitative parameters of 18F-FDG PET/CT, and survival. We pooled hazard ratios (HRs) to evaluate the prognostic value of the maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) for overall survival (OS) and progression-free survival (PFS). Results: A total of 22 studies (1363 patients, average age range 30–88 years) were included. Baseline 18F-FDG PET/CT-derived MTV was significantly associated with both OS (HR: 1.124, 95% confidence interval (CI) 1.058–1.195, I2 = 81.70%) and PFS (HR: 1.069, 95% CI: 1.016–1.124, I2 = 71.80%). Other baseline 18F-FDG PET/CT-derived parameters, including SUVmax (OS: HR: 0.930, 95% CI: 0.718–1.230; PFS: HR: 0.979, 95% CI: 0.759–1.262), SUVmean (OS: HR: 0.801, 95% CI: 0.549–1.170; PFS: HR: 0.688, 95% CI: 0.464–1.020), and TLG (OS: HR: 0.999, 95% CI: 0.980–1.018; PFS: HR: 0.995, 95% CI: 0.980–1.010), were not associated with survival. Sensitivity analyses by removing one study at a time did not significantly alter the association between MTV and PFS or between MTV and OS. There was no evidence of publication bias. Conclusion: Pretreatment baseline 18F-FDG PET/CT-derived MTV might be a prognostic biomarker in NSCLC patients receiving immunotherapy. Further studies are needed to support routine use. Plain language summary Using PET/CT scans to predict survival in lung cancer patients receiving immunotherapy: a study review Aims and Purpose of the Research We wanted to know if a type of scan called 18F-FDG PET/CT can help predict how long people with a type of lung cancer (NSCLC) will live after treatment with immunotherapy. Background of the Research This research matters because NSCLC is a common and serious type of lung cancer. Knowing how long patients might live after treatment can help doctors plan b