Using "PET Response Criteria in Solid Tumors (PERCIST)" in Evaluating Response to Neoadjuvant Chemoradiotherpy for Esophageal Cancer

Background: Esophageal cancer is one of the leading malignancies in Taiwan. Accuracy tumor staging can direct to appropriate therapy planning and provide prognostic implications. Positron emission tomography (PET) with [18F]-fluoro-2-deoxy-D-glucose (FDG) has been shown to have better N staging and prognostic stratification abilities than conventional imaging modalities, such as endoscopic ultrasonography (EUS) and CT.

Purpose: This study is aimed to evaluate the effectiveness of 18F-FDG PET in the initial staging, therapy planning, and therapeutic response monitoring for esophageal cancer patients.

Method: Patients with pathological proven esophageal cancer, age 20-90 year-old, will be included in this study. Each patient will receive a baseline PET study. For those patients who received pre-operative CCRT, another PET will be performed 1-4 weeks after completion of CCRT.

Primary outcome: 1. The incremental staging information by using 18F-FDG PET 2. The impact of the PET results on the patients' subsequent therapy planning 3. To compare treatment response using RECIST criteria and FDG PET results.

Secondary outcome: To correlate the PET response rate and the patients' disease free survival and overall survival.