Endoscopic ultrasound: current role and future perspectives in managing rectal cancer patients.

As therapeutic regimens for rectal cancer have seen considerable changes, an accurate staging is mandatory for choosing the adequate strategy. Locoregional staging is the decisive factor in selecting patients for neoadjuvant chemoradiation therapy and for determining the extent of surgery. Endoscopic ultrasound (endorectal ultrasound--ERUS) is a very effective method for assessing the local extent of rectal cancer, especially regarding the depth of tumor infiltration. Although a significant limitation is represented by its lower accuracy for diagnosis of lymph node metastases, this is still a point of concern for other imaging tests as well. In this review we report the current data on ERUS, presenting both its advantages and limitations, and making a comparison to other staging methods. Recent developments of the technology that might enhance staging accuracy are also discussed.