Oncological outcome of T1 rectal cancer undergoing standard resection and local excision

Aim We studied the outcome and prognostic factors for T1 rectal cancer patients undergoing standard resection or transanal excision. Method One hundred and twenty‐four patients with T1 rectal cancer were included in the study, of whom 66 (53.2%) underwent standard resection and 58 (46.8%) underwent transanal excision. Survival analysis was performed to compare the outcome. Results The 5‐year local recurrence rate was 11.0% in the transanal excision group versus 1.6% in the standard resection group (P = 0.031) but the 5‐year disease‐free survival and overall survival rates were not significantly different between the two groups. Multivariate analysis suggested that a high tumour grade and perineural or lymphovascular invasion were independent risk factors for local recurrence and recurrence‐free survival. For high‐risk patients (with at least one of the above risk factors), the 5‐year local recurrence and 10‐year recurrence‐free survival rates were 21.2% and 74.5%, versus 1.2% and 92.0% in low‐risk patients (P = 0.00003 and P = 0.003). In patients undergoing transanal excision, none in the low‐risk group had local recurrence during follow up, while 40% (6 of 15) of patients in the high‐risk group developed local recurrence within 5 years after surgery. The 5‐year local recurrence rate was 45.0%. Conclusion Transanal excision in T1 rectal cancer may result in a high rate of local failure for patients with a high‐grade tumour, or perineural or lymphovascular invasion. Local excision should be avoided as a curative treatment in high‐risk patients.