Prognostic significance of FDG PET/CT parameters in patients with non-small cell lung cancer of radiotherapy

Objective To investigate the metabolic parameters of primary lesions of non-small cell lung cancer (NSCLC) obtained by 18F-FDG PET/CT and their prognostic values in patients with NSCLC who underwent radiotherapy. Methods The clinical data of 170 NSCLC patients who underwent PET/CT scan before the first course of radiotherapy in Cancer Hospital, Chinese Academy of Medical Sciences, from January 2007 to December 2013 were analyzed retrospectively. The prognostic values of clinical factors, maximum standard uptake value (SUVmax) standard uptake value (SUVmean), metabolic tumour volume (MTV), and total lesion glycolysis (TLG) were analyzed. The Kaplan-Meier method was applied for univariate survival analysis, the log-rank test was applied to compare the survival rate between groups, and the Cox proportional hazards regression was applied for multivariate survival analysis; P<0.05 was considered statistically significant. The number of patients who received the follow-up visit at 5 years were 48. Results The 5-year overall survival was 24.7%. The univariate analysis showed that age, N stage, clinical TNM stage, tumor size, SUVmax, MTV, and TLG were the prognostic factors in NSCLC patients who underwent radiotherapy (P=0.001-0.040). The Cox proportional hazards regression analysis of the above parameters showed that age and MTV of the primary lesion were the independent prognostic factors for overall survival (P=0.016, 0.005). Conclusions Age, N stage, clinical TNM stage, tumor size, SUVmax, MTV, and TLG are the prognostic factors in NSCLC patients undergoing radiotherapy, while age and MTV of the primary lesion are the independent prognostic factors. Key words: Lung neoplasms/radiotherapy; Tomography, positron-emission; Tomography, X-ray computed; Fluorodeoxyglucose; Prognosis