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

To determine whether whole-body metabolic tumor burden, measured as either metabolic tumor volume (MTVWB) or total lesion glycolysis (TLG(WB)), 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 F-18-FDG-PET/CT scan imaging before therapy. The MTVWB, TLG(WB), 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), TLG(WB) (HR = 1.47, p < 0.001). The patients with a MTVWB a parts per thousand currency sign median of 65.7 ml and TLG(WB) a parts per thousand currency sign median of 205.11 SUVmean * ml had a median OS of 41.1 and 35.4 months compared with 9.5 and 9.7 months for those with a MTVWB > 65.7 ml and TLG(WB) > 205.11 SUVmean * ml, respectively. From a series of multivariate Cox regression models, the MTVWB and TLG(WB) 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 TLG(WB) as metabolic tumor burden measurements in F-18-FDG-PET/CT are independent prognostic markers and are significantly better than SUVmaxWB and SUVmeanWB at prognostication.