Prognostic Value of Metabolic Tumor Volume Measured by 18F-FDG PET/CT in Esophageal Cancer Patients

OBJECTIVE In this study, we aimed to explore prognostic importance of definition of preoperative metabolic tumor volume in esophageal cancer patients. METHODS 22 patients who have histologically proven stage IIA-III esophageal cancer and underwent (18)F-FDG PET/CT for preoperative staging of disease were included to the study. After (18)F-FDG PET/CT, all the patients underwent surgery within 4 weeks period. Patients have been followed up until death or Sept 15(th), 2012. Dates of death were recorded for survival analysis. During evaluation of (18)F-FDG PET/CT images, metabolic tumor volumes were calculated by drawing the isocontour region of interests from all visually positive FGD uptake lesions. RESULTS 22 patients (15M, 7F; mean age: 65.1±8.4, min-max:48-80) underwent (18)F-FDG PET/CT for preoperative staging of esophageal cancer. Preoperative diagnosis was squamous cell and adeno cancer in 17 (%77) and 5 (%23) patients, respectively. Location of primary tumor is distal, proximal and mid-esophagus in 13 (%59), 6 (%27) and 3 (%13) patients, respectively. Primary tumor of all the patients were FDG avid (mean SUVmax: 18.85±7.0; range: 5.5-35.1). Additionally, (18)F-FDG uptake was seen in mediastinal lymph nodes in 13 patients (5.45±8.15; range: 2.6-29.9). Mean metabolic tumor volumes of primary esophageal lesions were calculated as 8.77±8.46cm(3) (range: 2.3-34.2). Mean MTV of lymph nodes was 2.44±1.01cm(3) (range: 0.4-3.6). Mean total metabolic tumor volume was calculated as 9.99±8.58cm(3) (range: 2.3-27.3). 10 patients died during 447±121 days follow-up period. Mean survival time was 11.9±1.5 months (95%CI: 8.99-14.74) for entire patient group. Total metabolic tumor volume had a significant effect on survival (p=0.045) according to Cox proportional hazards regression analysis. One unit increase in MTV caused 1.1 (95%CI:1.003-1.196) fold increase in hazard, at any time. CONCLUSION Definition of preoperative metabolic tumor volume has a prognostic value in the prediction of postoperative survival times. Patients who have higher preoperative metabolic tumor volumes could be good candidates for more aggressive chemo-radiation therapy regiments. CONFLICT OF INTEREST None declared.