Local residual tumor predicts poor patient survival after resection for colorectal cancer. The aim of this study was to determine the prevalence of residual tumor in a line of resection in a large prospective series and to identify other pathology variables that may influence survival in the absence of distant metastases in such patients.

This study was based on all patients who had a resection for colorectal cancer at Concord Hospital between 1971 and 2001. Patients were followed up annually until death or December 2002. Survival analysis used the Kaplan-Meier method and log rank test. Proportional hazards regression was used in multivariate modeling.

The overall prevalence of residual tumor in a line of resection was 5.9%. Of 12 pathology variables examined, only high grade and apical node metastasis were independently associated with survival in the subset of 120 patients with residual tumor in a line of resection but without distant metastases. The 2-year survival rate for patients with neither of these adverse features was 46.4% (95% CI, 31.7% to 59.9%) as compared with only 7.7% (CI, 0.5% to 29.2%) in those who had both.

These results show that presence of local residual tumor after colorectal cancer resection does not carry a universally poor prognosis. Two specific histopathologic features independently associated with diminished survival were identified.