Prognostic value of pre-treatment maximum standardized uptake value and CRP in radiotherapy of esophageal cancer

The aim of the present study was to evaluate the prognostic value of the pre-treatment maximum standardized uptake value (SUVmax) and CRP in patients who underwent chemoradiotherapy for esophageal squamous cell carcinoma. A retrospective review of 69 consecutive patients with esophageal cancer who underwent concurrent chemoradiotherapy between 2013 and 2016 was performed. The total radiotherapy doses were 50, 50.4 or 60 Gy. The endpoints of the present study were overall survival (OS) and disease-free survival (DFS). The median follow-up for censored cases was 45.7 months. In 56 patients, F-18-fluorodeoxyglucose positron emission tomography was performed within 1 month prior to chemoradiotherapy. Data on CRP within 1 month prior to chemoradiotherapy were available for all patients. In the group of SUV max >12.85, the rates of 2-year OS and DFS were 49.0 and 35.7%, respectively. In the group of SUVmax <= 12.85, these values were 72.4 and 67.1%, respectively (P=0.048 and P=0.057, respectively). In the group of CRP >= 1 mg/dl, these percentages were 38.5 and 25.0%, respectively. In the group of CRP <1 mg/dl, these rates were 71.2 and 59.7%, respectively (P=0.013 and P<0.001, respectively). A multivariate analysis revealed that pre-treatment serum CRP levels remained an independent prognostic factor for both OS and DFS [OS: hazard ratio (HR), 0.25, P=001; DFS: HR, 0.28, P=0.005]. In conclusion, high SUVmax was associated with lower OS, while high CRP was associated with lower OS and DFS.