Prognostic value of total lesion glycolysis and metabolic active tumor volume in non-small cell lung cancer

Abstract

Introduction: To predict the outcome of patients with non-small cell lung cancer (NSCLC) the currently used prognostic system (TNM) is not accurate enough. The prognostic significance of the SUV_max measured by PET remains controversial. This study aims to evaluate the prognostic value in overall survival and progression free survival of SUV_max, the total lesion glycolysis (TLG) and the mean metabolic active volume (MATV) in NSCLC.

Methods: We retrospectively reviewed 105 patients (72 males, 33 females) with a new diagnosis of NSCLC (TNM stage I: 27.6%, II: 10.5%, III: 40.9% and IV: 21.0%) who underwent scanning with a PET/CT. For VOI definition a semi-automatic delineation tool was used. On PET images SUV_max, SUV_mean and MATV of the primary tumor and the whole tumor burden were measured. TLG and MATV were measured by using a threshold of 50% of SUV_max.

Results: OS and PFS are found to be higher in patients with low-SUV_Tmax and low-TLG_T values. OS and PFS were significantly higher for low-SUV_WTBmax, low-MATV_WTB and low-TLG_WTB values of the whole-tumor burden. Multivariate analysis of the whole-tumor burden revealed that the most important prognostic factors for OS are high MATV_WTB and TLG_WTB values, increasing stage and male gender. TLG_WTB and stage are also independent prognosticators in PFS.

Conclusion: Only whole-body TLG is of prognostic value in NSCLC for both OS and PFS. Stratification of patients by TLG_WTB might complement outcome prediction but the TNM stage remains the most important determinant of prognosis.

Microabstract: In order to predict the outcome of patients with non-small cell lung cancer (NSCLC) the currently used prognostic system (TNM) is not accurate enough. The prognostic significance of the standard uptake value (SUV) measured by PET remains controversial. This study aims to evaluate the prognostic value in overall survival (OS) and progression free survival (PFS) of the standard uptake value (SUV), the total lesion glycolysis (TLG) and the mean metabolic active volume (MATV) in NSCLC. The study reveals that TLG of the whole-tumor burden is an independent prognostic factor for OS and PFS in patients with NSCLC.