Independent prognostic value of whole-body metabolic tumor burden from FDG-PET in non-small cell lung cancer

Abstract

To determine whether whole-body metabolic tumor burden, measured as either metabolic tumor volume (MTVWB) or total lesion glycolysis (TLGWB), using FDG-PET/CT is an independent prognostic marker in non-small cell lung cancer (NSCLC). 328 patients with histologically proven NSCLC were identified for this retrospective analysis. This study was approved by our Institutional Review Board. All patients underwent baseline (18)F-FDG-PET/CT scan imaging before therapy. The MTVWB, TLGWB, maximum standardized uptake value (SUVmaxWB) and mean standardized uptake value (SUVmeanWB) of tumors throughout the whole body were measured from FDG-PET images with semi-automated 3D contouring software. In univariate analysis, there was a statistically significant association of overall survival (OS) with the MTVWB (hazard ratio (HR) = 1.62, p<0.001), TLGWB (HR = 1.47, p<0.001). The patients with a MTVWB≤ median of 65.7ml and TLGWB≤ median of 205.11 SUVmean * ml had a median OS of 41.1 and 35.4months compared with 9.5 and 9.7months for those with a MTVWB >65.7ml and TLGWB>205.11SUVmean * ml, respectively. From a series of multivariate Cox regression models, the MTVWB and TLGWB were significantly better than SUVmaxWB and SUVmeanWB at prognostication and significantly associated with patients' OS with HRs of 1.50 (p<0.001) and 1.42 (p<0.001), respectively, after adjustment for patient's age, gender and treatment intent as well as the tumor SUVmaxWB, histology and stage. MTVWB and TLGWB as metabolic tumor burden measurements in (18)F-FDG-PET/CT are independent prognostic markers and are significantly better than SUVmaxWB and SUVmeanWB at prognostication.