Carcinomas of the colon and rectum. A comparison of staging classifications.

Five staging methods for colorectal cancer were compared to the Dukes method in order to assess which methods were most sensitive and specific. Three hundred fifty-two patients with resected carcinomas of the colon and rectum were followed from 6 to 11 years or until death. All patients were staged by intraoperative and pathological criteria. Survival curves were constructed for each stage. The pTNM system was most sensitive at predicting death. The Gastrointestinal Tumor Study Group (GITSG) system was the most specific at predicting survival. However, the Dukes system did no worse than either of these staging systems and predicted relatively few false-positive and false-negative cases. The sensitivity and correctness of the Dukes system was improved by adding information regarding percent of lymph node metastases, ulceration of the primary tumor, and adjacent organ invasion.