Relationship between Overall Survival of Patients with Non-Small Cell Lung Cancer and Whole-Body Metabolic Tumor Burden Seen on Postsurgical Fluorodeoxyglucose PET Images.

Abstract

To test the hypothesis that whole-body metabolic tumor burden (MTBWB) on postsurgical fluorodeoxyglucose (FDG) positron emission tomographic (PET)/computed tomographic (CT) images in patients with non-small cell lung cancer (NSCLC) is associated with their overall survival (OS). The institutional review board approved this study and waived the requirement for obtaining informed consent. One hundred forty-two patients with NSCLC (69 men, 73 women; median age, 67.7 years) who underwent postsurgical FDG PET/CT were retrospectively reviewed. The whole-body metabolic tumor volume (MTVWB), whole-body total lesion glycolysis (TLGWB), and whole-body maximum standardized uptake value (SUVWBmax) were measured. OS served as the primary end point of the study. Kaplan-Meier curves and Cox regression were used to assess the association between PET/CT markers and OS. The interobserver variability was low, as demonstrated with intraclass correlation coefficients higher than 0.94 for SUVWBmax, MTVWB, and TLGWB. When compared with those with negative postsurgical FDG PET/CT findings, a significant decrease of OS was found in patients with the presence of FDG-avid tumor on the basis of both a log-rank test (P = .001) and a univariate Cox model (hazard ratio = 2.805, P = .001). In patients with FDG-avid tumor, there was a significant association between OS and ln MTVWB (P < .001), ln TLGWB (P < .001), and ln SUVWBmax (P < .010) in either univariate or multivariate analysis, after adjusting for patient age, sex, TNM restage, and therapy after postsurgical PET/CT studies. The OS differences between the groups dichotomized by the median value of MTVWB (11.54 mL, P = .004), TLGWB (32.38 mL, P < .001), or SUVWBmax (4.93, P = .023) were significant. MTBWB and tumor maximum standardized uptake at postsurgical FDG PET/CT are related to the patient's OS in NSCLC, independent of age, sex, TNM restaging, and therapy after postsurgical PET/CT studies.