What pathologic features influence survival in patients with local residual tumor after resection of colorectal cancer?

Background: 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.
Study Design: 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.
Results: 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.
Conclusions: 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.