The role of pretreatment FDG-PET in nasopharyngeal carcinoma treated with intensity-modulated radiotherapy.

Abstract

Pretreatment with 2- [(18)F] fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) was evaluated as a predictor of local failure-free survival (LFFS), disease-free survival (DFS), and overall survival (OS) in patients with nonkeratinizing nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT) alone or concurrently with chemotherapy (CCRT). Seventy-five M0 NPC patients who received FDG-PET before treatment were analyzed. The primary tumor FDG uptake was measured as the maximum standardized uptake value (SUVmax). The LFFS, DFS, and OS were calculated by the Kaplan-Meier method, and the differences were evaluated on log-rank test. The prognostic significance was assessed by univariate and multivariate analyses. Eighteen patients received IMRT alone and 57 received CCRT. The mean SUVmax was significantly higher in 12 patients with locoregional or distant failure than in those without failure (p <0.001). On multivariate analysis, the SUVmax was the only significant variable for 5-year LFFS (p = 0.017) and DFS (p = 0.000) but not for OS (p = 0.065). SUVmax is a potential independent prognostic predictor of clinical outcomes in patients with nasopharyngeal carcinoma treated with IMRT alone or with CCRT. A high (18)F-FDG uptake (SUVmax >5) indicates poor outcome in patients with NPC.