[Risk factors analysis of the early colorectal carcinoma after endoscopic non-curative resection: A retrospective clinical study of 56 cases]

Objective: To explore the risk factors contributing to the progression-free survival rate of patients undergoing endoscopic non-curative resection.

Methods: Clinicopathological data of patients with early colorectal carcinoma and intraepithelial neoplasia undergoing endoscopic resection in our department from January 2009 to January 2015 were collected. Associated factors affecting the progression-free survival rate of the early colorectal carcinoma after endoscopic non-curative resection were analyzed. Any of the following conditions was defined as endoscopic non-curative resection: (1) positive lateral or vertical cutting margin; (2) submucosa invasion depth ≥1 000 μm; (3) vascular or lymphatic invasion; (4) low differentiation, including signet ring cell carcinoma or mucinous adenocarcinoma; (5) high grade tumor budding.

Results: Clinicopathological data of 840 cases were collected. According to China's Endoscopic Screening, Diagnosis and Treatment Guidelines for Early Colorectal Cancer, 56(56/840, 6.7%) cases were defined as the non-curative resection, the metastasis or recurrence rate was 14.3%(8/56), 3-year progression-free survival rate was 85.7%(48/56), and 3-year overall survival rate was 94.6%(53/56). Univariate prognostic analysis showed that 3-year progression-free survival rate in low and moderate-high differentiation adenocarcinoma was 25.0% and 90.4%(χ²=6.711, P=0.010), in patients with submucosa invasion depth ≥2 000 μm and <2 000 μm was 75.0% and 93.8%(χ²=6.745, P=0.009), and in patients with and without vascular or lymphatic invasion was 60.0% and 88.2%(χ²=7.708, P=0.005), whose differences were all significant. Multivariate Cox regression analysis revealed that low differentiation adencarcinoma (P=0.015, HR=8.021, 95%CI: 1.499-42.921), invasion depth ≥2 000 μm (HR=6.823, 95%CI: 1.299-35.848) and vascular or lymphatic invasion (HR=18.143, 95%CI: 2.079-158.358) were independent risk factors for the progression-free survival rate of the early colorectal carcinoma after endoscopic non-curative resection.

Conclusion: Pathology after endoscopic non-curative resection for early colorectal carcinoma indicates that low differentiation adenocarcinoma, submucosa invasion depth ≥2 000 μm and vascular or lymphatic invasion are independent risk factors of poor prognosis.