Endoscopic ultrasonography using a miniprobe for staging of stenotic esophageal cancer

Using miniprobes even highly stenotic tumors can be examined. The aim of the study was to assess the accuracy of miniprobe EUS (MEUS) in staging stenotic esophageal cancer.

Between January 2001 and July 2004, n=97 consecutive patients with esophageal cancer having preoperative EUS and/or MEUS and undergoing esophageal resection were included in the study. Patients receiving neoadjuvant treatment protocols or not having a complete tumor resection were excluded, as they did not provide a valid pathohistology. Endoscopic features were also used as diagnostic tests for discriminating T0–2 vs. T3–4.

The overall staging accuracy was 60.8% (50.4–70.6) for T stage and 74.2% (64.3–82.6) for N stage. Staging accuracy for T stage was not different for miniprobe alone in stenotic tumors (59.6%) versus conventional probe + miniprobe in non-stenotic tumors (63.2%, p=0.83). Discrimination of T0–2 vs. T3–4 stages had an accuracy of 78.9% for conventional probe + miniprobe and 64.9% for miniprobe alone (p=0.17). This differentiation was better for tumors located in the esophagus than in the cardia (75.7% vs. 52.2%, p=0.04). Based on the preoperative EUS results, 82.5% of patients would have been assigned to the appropriate therapy protocol (neoadjuvant therapy, if T3–4 and/or N pos.). Using the endoscopic tumor length as a diagnostic test for differentiation of T0–2 vs. T3–4 tumors (cut-off 5cm), the test accuracy was 71.3% (p=0.87 vs. EUS), providing a sensitivity of 64.7% and a specifity of 75.5%.

MEUS used for stenotic esophageal cancers provided the same accuracy for T and N stage as the conventional probe used for non-stenotic tumors. Therefore, MEUS should be routinely used for stenotic tumors. Obviously clinical routine use of EUS leads to lower accuracies than reported in smaller series.