Role of endoscopic ultrasonography in diagnosis, staging, and outcome of gastrointestinal diseases.

Using endoscopic ultrasound imaging, highly accurate gastrointestinal tumor characterization and staging is now possible without surgery. Precise endosonographic preoperative staging allows use of the TNM pathological staging system to stratify treatment for esophageal, gastric, rectal, and pancreatobiliary tumors. Endoscopic ultrasonography often establishes a diagnosis in malignant and, in certain patients, benign disease; accurately evaluates anastomoses for recurrent tumor; and characterizes submucosal masses. When histology is required, endoscopic ultrasonography has a critical role in defining an abnormal area for deep submucosal biopsy from the gastrointestinal lumen. Endoscopic ultrasonography is unsurpassed in determining resectability of gastrointestinal neoplasms. It can be used to monitor treatment of downstaged tumors prior to attempted resection. Using endoscopic ultrasonography for earlier diagnosis and precise staging will significantly improve the clinical outcome of patients with gastrointestinal disease as significant advances both in surgical techniques and in combined chemotherapy and radiotherapy continue to be made and applied selectively.