The Prognostic Value of Baseline 18F-FDG PET/CT in Stage IV Non–Small Cell Lung Cancer Patients Receiving Osimertinib Treatment

Purpose: This study aimed to evaluate the role of various metabolic parameters derived from baseline 18 F-FDG PET/CT in predicting the prognosis of stage IV non–small cell lung cancer (NSCLC) patients scheduled to receive osimertinib treatment. Patients and Methods: A retrospective analysis was conducted on 177 NSCLC patients (98 males, 79 females; mean age 58.5 ± 11.0 y) who underwent osimertinib therapy and 18 F-FDG PET/CT scanning before treatment. Clinical and PET/CT parameters were assessed, including age, sex, smoking history, brain metastasis, bone metastasis, CEA level, SUVmax, SUVmean, SUVpeak, metabolic tumor volume (MTV), and total lesion glycolysis (TLG). Receiver operating characteristic (ROC) curve analysis was used to calculate the optimal cutoff values for all parameters. Progression-free survival (PFS) was analyzed using log-rank tests, Kaplan-Meier curves, and Cox proportional hazard models to identify prognostic markers. Results: The mean follow-up period was 15.24 ± 8.14 months. Univariate analysis revealed that SUVmax, SUVmean, MTV, and TLG were significantly associated with PFS, with cutoff values of 12.3, 8.57, 13.49 cm 3 , and 162.37, respectively. The hazard ratios were 1.776 ( P = 0.007), 2.155 ( P ＜0.001), 3.312 ( P < 0.001), and 3.370 ( P < 0.001), respectively. Multivariate survival analysis indicated that MTV was an independent prognostic factor for PFS (HR = 2.323; P = 0.012). Conclusions: Baseline PET/CT metabolic parameters before osimertinib treatment may help identify potential NSCLC patients who could derive clinical benefit, and baseline MTV of the primary tumor from 18 F-FDG PET/CT is a reliable prognostic indicator for PFS in stage IV NSCLC patients treated with osimertinib.