Abstract

Introduction: Preoperative T staging of rectal cancer is essential for an adequate treatment strategy. Endoscopic ultrasonography (EUS) is one of the available modalities. The reported accuracy of this technique for T staging is variable. This inconsistency might be due to neoadyuvancy, and its downstaging properties. Aim: Determine the accuracy of rectal EUS for T staging of middle and lower rectal tumors in patients not treated with neoadyuvant chemo-radiotherapy. Materials and Methods: Clinical records of all consecutive patients evaluated by rectal EUS between years 2001-2009 in the Catholic University Clinical Hospital were accessed. Of 2.120 patients, 294 had the exam performed for middle or lower rectal cancer. Those who did not receive neoadyuvant chemo-radiation and whose histopathology was available were analyzed. Result: Data was obtained for 69 patients. The overall accuracy of EUS for T staging was 85%. For T1 tumors, the sensibility, specificity and accuracy were 82%, 96% and 94% respectively. For T2 tumors the sensibility, specificity and accuracy were 72%, 83% and 78 respectively. For T3 tumors the sensibility, specificity and accuracy were 82%, 83% and 83% respectively. Conclusion: Rectal EUS continues to be a valuable staging procedure for tumor depth invasion, with an overall accuracy of 85%.