To explore the application effect of "four-step" dissection of lymph node No.253 in radical resection of rectal cancer with left colic artery (LCA) preserved.

A total of 90 patients who received laparoscopic radical resection for rectal cancer from January 2020 to May 2021 were retrospectively selected and divided into two groups according to digital table method, with 45 cases in each group. Low ligation of inferior mesenteric artery (IMA) to retain LCA and No.253 lymph node dissection were performed during the operation. The control group was cleaned by traditional method, and the observation group was cleaned by "four-step method". SPSS 19.0 software was used to analyze the data. Perioperative relevant indicators, No.253 lymph node dissection and other indicators were expressed by (), and independent sample t test was performed. The occurrence of complications was represented by [cases (%)], and χ² tests were performed. Survival was analyzed by Kaplan-Meier method and Log-Rank test was performed. P<0.05 was considered statistically significant.

The operation time of observation group was shorter than that of control group (P<0.05). There were no significant differences in other perioperative indicators, lymph node dissection, postoperative complication rate, postoperative recurrence rate, metastasis rate and cumulative 3-year overall survival rate between 2 groups (P>0.05).

"Four-step" lymph node dissection for No.253 in laparoscopic radical resection of rectal cancer with LCA preservation can effectively shorten the operation time, has similar lymph node dissection effect and prognosis with traditional methods, and does not increase the occurrence of postoperative complications, so it is safe and feasible.