Endoscopic ultrasound for preoperative staging of esophageal carcinoma

Endoscopic ultrasound (EUS) is potentially the best method for pretreatment staging of esophageal carcinoma once distant metastases have been excluded by other methods. However, its apparent accuracy might be influenced by the use of neoadjuvant therapy. To determine the accuracy of EUS in patients undergoing esophageal resection, the authors reviewed their experience with EUS.

A total of 73 patients with esophageal carcinoma who underwent an esophagectomy between April 2000 and February 2005 were examined using preoperative EUS and computed tomography (CT). Of these patients, 39 also underwent preoperative neoadjuvant chemoradiotherapy. Both EUS and CT scan were used to determine the depth of tumor penetration (T-stage) and the presence of lymph node metastases (N-stage). These results then were compared with staging determined after pathologic examination of the resected surgical specimen.

For patients not undergoing neoadjuvant therapy, T-stage was accurately determined by EUS in 79%, N-stage in 74%, and tumor node metastasis (TNM) classification in 65% of the cases. However, when patients who had undergone neoadjuvant chemoradiotherapy were included, the overall accuracy of EUS was 64% for T-stage, 63% for N-stage, and 53% for TNM classification. For the patients who underwent neoadjuvant therapy, EUS indicated a more advanced T-stage in 49%, N-stage in 38%, and TNM classification in 51% of the cases, as compared with pathology. The overall accuracy of EUS for T- and N-stage carcinomas was superior to that of CT scanning.

For patients who do not undergo preoperative neoadjuvant chemotherapy and radiotherapy, EUS is a more accurate method for determining T- and N-stage resected esophageal carcinomas. Neoadjuvant therapy, however, results in apparent overstaging, predominantly because of tumor downstaging, and this reduces the apparent accuracy of EUS (and CT scanning) in this patient group. Nevertheless, EUS staging before neoadjuvant therapy could be more accurate than pathologic staging after treatment, thereby providing better initial staging information, which can be used to facilitate treatment.