Abstract
A total of 2994 cases of previously untreated colorectal carcinomas taken from the database of the International Cancer Patient Data Exchange System of the UICC were analyzed. The objective was to compare pretherapeutic and postsurgical data and to investigate the impact of missing information on the quality of tumor staging under routine conditions. In clinical staging, a higher percentage of items were marked "unknown" in the questionnaires than in histopathological staging. The clinical and postoperative assessment of TNM stages Ib, II, and III frequently diverged, indicating a low precision for clinical staging. Fistulae were rarely observed in either colon or rectum carcinoma.