LAUSR

Objective This study explored whether integrated texture parameter (ITP) of the fluorine-18-fluorodeoxyglucose PET (18F-FDG PET) is a stratification factor for the survival of nonoperative patients with locally advanced non-small-cell lung cancer (LA-NSCLC). Patients and methods Thirty-five patients with LA-NSCLC treated with chemoradiotherapy or radiotherapy were included in the retrospective study. Eight principal components (PCs) were extracted from 72 18F-FDG PET texture features (TFs) using PC analysis. The survival rates between PC subgroups (group by median value) were compared using Kaplan–Meier method. Seventy-two factor loadings for PC7 were evaluated using t-test. Standardized values of the TFs with significant factor loading were multiplied by the corresponding PC7 component coefficient, and the products were added together to obtain ITP. The survival rates between ITP subgroups (group by median value) were compared using Kaplan–Meier method. Patient characteristics between ITP subgroups were compared using &khgr; 2-test, Mann–Whitney U-test, or t-test. Results The median follow-up time was 20.7 months. The median overall survival (OS) and progression-free survival (PFS) were 32.5 and 14.4 months, respectively. The patients with high PC7 value had lesser OS (P=0.006) and PFS (P=0.010) than those with lower value. Factor loadings of standardized uptake value kurtosis, run percentage, and zone percentage were significant for PC7 (P<0.01). The patients with high ITP value had lesser OS (P=0.001) and PFS (P=0.002) than those with lower value. There were no significant differences in patient characteristics between ITP subgroups (P>0.2). Conclusion This study demonstrated that ITP might be a stratification factor for the survival of nonoperative patients with LA-NSCLC.