Does Local Excision Without Salvage Surgery Affect the Prognostic Outcome of Patients With Malignant Colorectal...

Management of malignant colorectal polyp has been a treatment dilemma for clinicians. This study aims to evaluate the long-term survival outcome of patients with and without salvage surgery after local excision.

From January 2000 to December 2022, patients with T1 malignant colorectal polyp diagnosed after local excision managed by two institutions were included for retrospective review. After propensity score matching, disease-free, cancer-specific, and overall survival between local excision alone (LE alone) group and local excision with salvage surgery (LE + SS) group were compared using Kaplan-Meier curves and log-rank test. Multivariate analysis was performed with Cox regression model to identify independent risk factors affecting disease-free survival.

Seventy-nine propensity score-matched pairs were extracted from 309 patients with a mean follow-up of 65.3 $\pm$ 42.6 months. There was no significant difference in the 8-year disease-free survival (LE alone, 86.7%; LE + SS, 90.4%; p = 0.206), cancer-specific survival (LE alone, 94.4%; LE + SS, 100%; p = 0.114) and overall survival (LE alone, 84.1%; LE + SS, 90.5%; p = 0.400). Piecemeal resection (HR, 7.051; 95% CI, 1.856-26.794; p = 0.004) and two or more pathological risk factors (HR, 8.552; 95% CI, 1.058-69.095; p = 0.044) were independent risk factors for worse disease-free survival in multivariate analysis. Salvage surgery and presence of single risk factor alone were not associated with disease-free survival.

Local excision alone is non-inferior to local excision followed by salvage surgery in terms of long-term oncological outcome. With better risk profile assessment, local excision alone can be a safe treatment option in patients with T1 colorectal cancer.