Background: Despite recent advances in imaging techniques, adequate classification of esophageal lesions is still challenging. Accurate staging of tumors of the esophagus is a precondition for targeted therapy. In this retrospective, multicenter study, we report the role of high-frequency endoscopic ultrasound (EUS) catheter probes in pretherapeutic staging of esophageal neoplasms and thus guiding treatment decisions.
Methods: A total of 143 patients (mean age of 63.8 ± 10.7 years) with esophageal carcinoma were recruited from five German centers (Münster, Oldenburg, Hannover, Wiesbaden, and Lüneburg). Tumor type was adenocarcinoma in 112 (78 %) cases and squamous cell carcinoma in 31 (22 %). Tumor localization was as follows: proximal 3, mid esophagus 7, and distal third 133. Histological correlation either through EMR or surgery was available. In all patients, pretherapeutic uT and uN classifications were compared to pT/pN classification obtained from surgically (esophagectomy, n = 93) or endoscopically (EMR, n = 50) resected tissue.
Results: Overall, accuracy of uT classification was 60 % and of uN classification was 74 %. Sensitivity, specificity, and accuracy rates for local tumor extension were as follows (%): T1: 68/97/83; T2: 39/84/75; T3: 72/81/79; T4: 13/97/93; T1/2: 73/81/75; T3/4: 78/82/81. Relating to positive lymph node detection, sensitivity and specificity were 76 and 71 %, respectively.
Conclusions: Miniprobe EUS is an established method for the staging of esophageal tumors. Our large multicenter cohort shows a solid accuracy of miniprobe EUS with respect to differentiating locally advanced from limited cancer and assisting to determine the treatment regimen in the era of neoadjuvant therapy; consequently, 78 % of patients would have been assigned to the adequate therapeutic regimen, whereas 11 % of patients would have been overtreated and 11 % undertreated.