The effect of non-curative endoscopic resection on cT1N0M0 colorectal carcinoma patients who underwent additional surgery

Background and aim: Radical surgery is recommended for T1 colorectal cancer with non-curative endoscopic resection. However, there is still insufficient evidence about whether the non-curative endoscopic resection prior to surgical resection affects the short-term and long-term outcomes of patients. The purpose of this study was to investigate the effect of non-curative endoscopic resection before surgical resection on short-term and long-term outcomes in patients with T1 colorectal cancer.

Patients and methods: Patients with clinical T1N0M0 (cT1N0M0) colorectal cancer who underwent direct surgery or additional radical surgery after non-curative endoscopic resection were collected. We evaluated postoperative complications and long-term prognosis between the two groups.

Results: From 2011 to 2017, 779 patients were clinically diagnosed with T1N0M0 colorectal cancer at Zhongshan Hospital. We assessed patients who underwent additional surgery following the prior non-curative endoscopic resection (n = 145) and patients who underwent radical surgery directly (n = 336). There was no significant difference in 5-year OS (99.3% vs. 99.4%, P = 0.866) and 5-year DFS (97.2% vs. 97.3%, P = 0.909) between the two groups. The total complication rate was slightly higher in prior endoscopic resection group (15.2% vs. 9.5%, P = 0.111). The 5-year OS and 5-year DFS of patients who refused additional surgery (n = 95) were significantly lower than ER prior to surgery group (For OS, 92.6% vs. 99.3%, P = 0.017; for DFS, 91.2% vs. 97.2%, P = 0.021).

Conclusion: In patients who underwent additional surgery, non-curative endoscopic resection of cT1 colorectal carcinoma did not have adverse effect on short-term and long-term outcomes. Additional surgery should be recommended in patients who received non-curative ER.