Positron emission tomography for the assessment of survival after subsequent surgery in multimodality treatment for patients with locally advanced esophageal squamous cell carcinoma.

Abstract

e14636 Background: Recent studies imply that positron emission tomography with fludeoxyglucose F 18(FDG-PET) correlates with histopathologic response and survival in patients with esophageal cancer undergoing neoadjuvant chemoradiotherapy (CRT) followed by surgical resection. To evaluate the rating system of FDG-PET after the completion of neoadjuvant CRT for the assessment of histopathologic response and prognosis inthe multimodality treatment of patients with esophageal cancer. Methods: Seventy patients (58 men, 12 women; median age, 61 years) with locally advanced esophageal squamous cell carcinoma who received neoadjuvant CRT underwent FDG-PET before chemoradiotherapy and transthoracic en bloc esophagectomy in evaluation of pathologic response to CRT and postoperative survival. Lack of FDG uptake was defined as primary tumors with SUVmax at least 2.5, and FDG-PET complete response after CRT (PET-CR) was defined as SUVmax<2.5 or SUVmax<3 with mild hyper metabolic activity around the primary tumor. Results: After CRT, lack of FDG uptake was noted 34 patients, PET-CR was noted 49 patients and pathological CR was noted 31 patients. PET-CR indicated stronger correlation with postoperative survival than lack of FDG uptake and rate of decrease in SUV. PET-CR and pathologic CR predicted for improved outcomes (3-year disease free survival 70.3% vs 42.6% P=0.0032; log-rank test, 76.4% vs 37.6% P=0.0008; log-lank test). But on multivariate analysis using the Cox proportional hazards model, only pathologic CR was found to be correlated with post-CRT disease free survival (HR 0.190, 95%CI 0.049-0.73, P=0.017). Conclusions: To evaluate the value of FDG-PET for the assessment of prognosis in the multimodality treatment for patients with locally advanced esophageal squamous cell carcinoma, we tried different rating system of FDG-PET but no recommendation was made for the use of FDG-PET.