Lymph Node With the Highest FDG Uptake Predicts Distant Metastasis-Free Survival in Patients With Locally Advanced Nasopharyngeal Carcinoma

PURPOSE: Distant failure is a major concern in patients with nasopharyngeal carcinoma. We evaluated whether the metabolic features on F-FDG PET/CT can predict distant metastasis-free survival (DMFS) in patients with locally advanced nasopharyngeal carcinoma. METHODS: We retrospectively reviewed 51 patients stage III, IVA, and IVB nasopharyngeal carcinoma who underwent F-FDG PET/CT at staging. The SUVmax for the primary site and the lymph nodes with the highest uptake as well as at the farthest station were divided by the SUVmean of the background liver (TLR, NLR-H, and NLR-F, respectively). The prognostic value of clinicopathologic factors and SUV parameters for predicting DMFS were assessed using a Cox proportional hazards model. Differences in DMFS were examined by the Kaplan-Meier method. RESULTS: In the median follow-up period of 50.4 +/- 39.3 months (median +/- interquartile range; range, 3.8-130.9), distant metastasis developed in 11 patients (21.6%). In univariate analyses, N stage (N3b) (P = 0.003) and NLR-H >5.70 (P = 0.02) were significant prognostic factors for DMFS, and remained significant in multivariate analysis, whereas TLR (P = 0.18) and NLR-F (P = 0.76) did not. The Kaplan-Meier curves showed significantly poorer DMFS in patients with NLR-H >5.70 than in those with lower NLR-H (</=5.70) (1-year DMFS rate, 84.2% vs 93.5%; P = 0.01). CONCLUSIONS: In addition to anatomical N stage, higher NLR-H on pretreatment F-FDG PET/CT is an independent prognostic factor for worse DMFS in patients with locally advanced nasopharyngeal carcinoma.restrictio