Endoscopic ultrasound downstage after neoadjuvant chemotherpy predicts survival of locally advanced esophageal cancer

Abstract

4196 Background: Endoscopic ultrasound (EUS) plays a central role in the initial staging and treatment of esophageal cancer (EC). Use of EUS for re-staging patients (pts) after neoadjuvant therapy is controversial. Few studies have suggested that EUS post-neoadjuvant therapy can accurately predict tumor response and overall survival in pts with locally advanced disease. Methods: EUS data from an ongoing study on neoadjuvant chemotherapy for locally advanced EC with Paclitaxel 125 mg/m2, Fluorodeoxyuridine 150 m/Kg or 80 mg/Kg, Leucovorin 500 mg/m2 and Cisplatin 100 mg/ m2 was collected. EUS performed pre- and post-chemotherapy in all pts. Maximum tumor thickness was measured on EUS pre- and post-chemotherapy and EUS stage compared to surgical pathology (AJCC TNM stage). More than 50% wall thickness reduction was classified as a response by EUS. Results: 38 pts were included, mean age 62 yrs. There were 35 adenocarcinomas of the gastroesophageal junction and three squamous cell carcinomas. The median follow-up time among 26 pts still alive was 19 months (range: 3–75 months). The 1-, 3- and 5-yrs overall survival was respectively: 88%, 63% and 45%. The 1- and 3-yrs survival of pts who had more than 50% reduction in tumor thickness after chemotherapy was superior to those with less than 50%: 1yr survival:92% vs. 85% and 3-yrs: 70% vs. 59% (p=0.39 Log-rank test). On EUS post- chemotherapy, patients who had either T or N downstage had better survival than those without downstage; 3-yrs survival: 88% vs. 40% respectively; p=0.004. Presence of N1 disease on surgical pathology was associated with worse 1- and 3-yrs survival: N0 disease (94% and 83%) vs. N1 disease (7% and 47%) (Log-rank test, p= 0.012). Conclusions: Patients with tumor response (>50% reduction of wall thickness) to neoadjuvant chemotherapy verified by EUS appears to have an improved survival but it did not reach statistical significance in our study at this point. Tumor downstaging after neoadjuvant chemotherapy verified by EUS and absence of nodes on pathological staging are associated with improved survival. The role of EUS appears promising in predicting patient’s survival based on tumor response after neoadjuvant chemotherapy. No significant financial relationships to disclose.