Pre-operative staging of recto-sigmoid colon carcinoma by upper gastrointestinal endoscopic ultrasonography

BACKGROUND/AIMS: To assess the accuracy of a new generation endoscopic ultr asonography (EUS) (GF-M200) in pre-operative staging of recto-sigmoid colon carcinoma invasion and lymph node metastasis. METHODOLOGY: Seventy-three patients with biopsy proven colon cancer were in cluded in this study. These comprised 60 patients with rectal carcinoma and 13 patients with sigmoid carcinoma. All patients were pre-operatively exam ined by EUS. Pathological findings of the depth of tumor invasion and prese nce of lymph node metastasis were correlated with EUS. RESULTS: EUS has an overall accuracy rate of 89% in staging of recto-sigmoi d cancer. The diagnostic accuracy rate was 83% for T1, 83% for T2, 93% for T3, and 71% for T4. Understaging and overstaging occurred in 6% and 6%, res pectively. In determining lymph node metastasis, the overall accuracy rate was 77%, with a sensitivity and specificity rate of 77% and 76%, respective ly. CONCLUSIONS: EUS is a valuable staging modality in the staging of the depth of tumor invasion, not only for rectal carcinoma but also for tumors locat ed at the sigmoid colon.