Prognostic value of metabolic volume measured by F-18 FDG PET-CT in patients with esophageal cancer

Abstract

Purpose: The aim of this study was to evaluate the usefulness of the metabolic tumor volume (MTV) measured by F-18 Fluorodeoxyglucose positron emission tomography (FDG PET-CT) in predicting recurrence free survival (RFS) in patients with esophageal cancer. Methods: Forty-five patients with squamous cell carcinoma, who had undergone whole-body F-18 FDG PET-CT scans before surgical resection, were included in this study. All patients were treated with Ivor-Lewis esophagectomy. The MTV was quantified within the primary tumor using the 50% threshold of the maximum standardized uptake value (SUV_max) of the FDG uptake areas. The cutoff value of MTV₅₀ was determined through receiver-operating characteristic curve. The Kaplan Meier method was used to find out the relationship between RFS and MTV₅₀. Univariate analysis and multivariate proportional hazards regression analysis were applied to test the significance of volumetric parameter of F-18 FDG PET-CT and other conventional prognostic factors for the prediction of RFS. Results: Overall median follow up period was 17.87 months (range: 1.07–63.27 months). The median survival between treatment completion and recurrence was 15.5 months (range: 1.37–72.43 months). Recurrence was found in eight patients. On univariate analysis, MTV₅₀ (P = 0.0032), N stage (P = 0.0004), American Joint Committee on Cancer stage (P = 0.0101), tumor location (P = 0.0054) and adjuvant treatment (P = 0.0373) were significant predictors of RFS. Multivariate analysis showed that the independent prognostic factors were MTV₅₀ (P = 0.0465), N stage (P = 0.0303) and tumor location (P = 0.0270). Conclusion: Volume based parameter of F-18 FDG PET-CT may have a role in providing prognostic information in esophageal cancer patients who received esophagectomy.