A Study Of The Relationship Between The Surgical Margins Of Laparoscopic Sigmoid Colon Cancer And The Prognosis And Of The Distribution Of Pericolic Positive Lymph Nodes

Objective:By analyzing the clinical and pathological differences between patients with sigmoid colon cancer with the shortest cut margin,to explore the influence of different short cut margins of laparoscopic sigmoid colon cancer on the prognosis of patients,and to explore the safe margin of sigmoid colon from the distribution rule of parenteral lymph nodes.Methods:Radical resection from Nanfang Hospital Southern Medical University Department of general surgery from January 2010 to January 2015 280 cases of laparoscopic sigmoid colon cancer patients with stage Ⅰ-Ⅲ,and according to the postoperative samples of different shortest margin will be divided into 3 groups(the shortest<5cm margin in 34 cases,more than 5cm and<10cm in 201 cases,more than 10cm in 45 cases),and the clinical data and prognosis were retrospectively analyzed.At the same time,we prospectively collected postoperative pathological specimens from 151 patients with sigmoid colon cancer from April 2016 to October 2017.The parenteral lymph nodes were grouped according to the distance from tumor to 2cm,2-5cm,5-7cm and>7cm,and the number and metastasis of lymph nodes at different distances were statistically analyzed.Results:A retrospective analysis of three groups of patients had no difference in baseline statistics,the median follow-up time was 37(3-93)months after three groups of patients with 3 year survival rate(82.4%,88%and 82.2%,P=0.398)had no significant difference,but the 5 year survival rate(64.4%,87.1%and 85.3%,P=0.002)were significantly different,the prognosis of patients with<5cm margin,margin is greater than or equal to 5cm and<10cm and prognosis of difference between the margin is greater than or equal to 10cm is not obvious.Multivariate analysis showed that the sigmoid colon was the shortest cut edge of<5cm is an independent risk factor for 5 years OS(HR 1.324,95%CI 1.107-1.584,P=0.001);at the same time found in the three group,the number of intestinal lymph nodes and adjacent positive rate difference(P=0.050,P=0.038),the number of lymph node resection margin<5cm and lymph node positive rate is lower than the other two groups.In a prospective study,5cm can obtain a sufficient distance from the tumor lymph node number(average number of 27.7),the farther away from the tumor lymph node,the less the number of positive lymph nodes;all of the tumors located at a distance of more than 5cm,near 5cm,found no positive lymph nodes;multivariate analysis showed that tumor distance 2cm positive lymph node is the distance from the tumor 2-5cm independent risk factors for the existence of positive lymph nodes(HR0.123,95%CI0.025-0.590,P=0.001).Conclusions:In the laparoscopic radical resection of sigmoid colon cancer,the prognosis of patients with short margin,margin for<5cm positive intestinal lymph node residual caused by poor prognosis,at a distance of more than 5cm in the range of tumors,not found positive intestinal lymph node,5cm for sigmoid colon was the shortest safe distance.