Radiologic staging of gastrointestinal neoplasms

With the advent of several noninvasive imaging methods, such as gray scale ultrasonography and computed tomography (CT), both of which can delineate not only local tumor spread but also distant metastases, there is a renewed interest in using radiologic methods for preoperative staging of gastrointestinal (GI) tumors. However, ultrasonographic examinations are often unsuccessful due to overlying bowel gas or adjacent bony structures. Because CT images are more readily accepted by the clinicians, CT has now become the procedure of choice for staging GI tumors in many centers. With recent improvements in scanning technology resulting in increased contrast sensitivity and better spatial resolution, a diagnostic CT scan can be obtained in almost every patient. In this article, the ability of CT as well as other imaging methods to detect local and distant metastases in patients with either newly diagnosed or suspected recurrent GI tumors is discussed. The role of the radiologic examination in the diagnosis of complications resulting from different types of treatment is also adressed.