[Preoperative tumor staging in rectal cancer--a prospective study].

A precise preoperative tumor staging is the prerequisite of distinct treatment planning and subtle operative regimen. Diagnostic contribution of the various examination techniques especially of imaging modalities were determined in a prospective study and correlated to intra- and postoperative findings. The TNM classification of malignant tumors of the UICC, both in its present valid and the modified form to be introduced in January 1987, formed the basis of our clinical diagnostic staging. Diagnostic accuracy in tumor staging increased significantly from 63.4% to 83.9%, if digital rectal examination, rectoscopy and barium enema were accompanied by computed tomography. Staging prediction solely concerning the surgically important differentiation between tumors "organ limited" (T1/T2 stage) and "organ extended" (T3/T4 stage) achieved an accuracy of 91/4 (97.0%).