Quality control of endoscopic ultrasound in preoperative staging of esophageal cancer

Background and study aims: Endoscopic ultrasonography (EUS) is generally established as the most sensitive diagnostic tool for the assessment of locoregional tumor stage in esophageal carcinoma. It therefore has a crucial impact on the decision whether patients should undergo surgery as primary treatment or should receive neoadjuvant therapy. This study retrospectively evaluates the accuracy of EUS in tumor and nodal staging of prospectively evaluated patients with esophageal carcinoma in relation to tumor type, tumor grading, tumor site, and the influence of dilation. Patients and methods: All 214 patients included in the study underwent surgery without neoadjuvant therapy and had tumor-free resection margins with no evidence of distant metastasis. EUS investigations were done at our Department of Interdisciplinary Endoscopy. EUS results were compared with the pathological findings. Results: EUS correctly identified T status in 141 patients (65.9%). The sensitivity and specificity in relation to T status were 68.1% and 98.2% respectively for T1, 40.9% and 83.4% for T2, 84.3% and 64.6% for T3, and 14.3% and 98.8% for T4. The overall diagnostic accuracy of EUS in relation to N status was 64.5% (n = 138); sensitivity and specificity for the diagnosis of N1 were 93.8% and 20%, respectively. Sixty-eight (80%) of 85 pNO-staged tumors were overstaged as uN1. Dilation had a significant influence on the accuracy of EUS staging in advanced tumors (P = 0.02), whereas tumor grading impacted on EUS staging in early tumors (P=0.01). Tumor site and tumor type did not show any influence. Conclusions: Endosonographic staging of esophageal carcinoma is still unsatisfactory. An improvement in staging accuracy may be achieved by adding fine-needle aspiration biopsy (FNA) to EUS, because FNA improves N-stage accuracy, but it has no bearing on T-stage accuracy.