[Clinical staging of malignant tumors of the digestive system by the TNM system].

Computed tomography has decisively improved the determination of the clinical stage of tumors of the esophagus- and rectum. This method enables tumors to be diagnosed and localized as well as the extend of tumor spread to adjacent organs and metastatic lymph node involvement to be evaluated in most cases without additional invasive imaging procedures. CT is rarely used for tumors of the stomach, small bowel and colon.