Laparoscopic Total Mesorectal Excision With Lateral Lymph Node Dissection And Total Mesorectal Excision Alone: A Short-term Control Study

Objective To explore the necessity,judgment of preoperative indicators,security,and feasibility of laparoscopy in total mesorectal excision(TME)add lateral lymph node dissection(LLND)for rectal cancer.Methods A retrospective collection of rectal cancer patients in the Anorectal Department of Gan Su Provincial Hospital from October 2019 to February 2021 who underwent laparoscopic TME with LLND and TME alone,combined with the inclusion and exclusion criteria,screened a total of 143 patients into this study.Among them,38 patients underwent laparoscopic TME with LLND as the L-TME+LLND group,and 105 patients underwent laparoscopic TME as the L-TME group.In the L-TME+LLND group,6 patients underwent LLND after neoadjuvant chemoradiotherapy(NACRT),as the L-TME+LLND-A group.32 patients received LLND without NACRT,as L-TME +LLND-B group.Based on the preoperative and postoperative data of patients in the L-TME+LLND-A group and the L-TME+LLND-B group,the necessity of LLND and the short-diameter cut-off value of the lymph node during LLND were analyzed.Combining the patient’s gender,age,BMI,American Society of Anesthesiologists classification,distance from the lower edge of the tumor to the anal edge,preoperative medical history,tumor diameter and pathological stage and other clinical baseline data,propensity score matching to match the baseline data of the two groups,and The 1:1 matching was achieved through the nearest neighbor matching method.L-TME+LLND group and L-TME group each had 30 cases successfully matched.After pairing,the intraoperative results,short-term postoperative results,postoperative pathological results,and complications within 30 days after the pairing were compared disease.Results In the L-TME+LLND-A group,2 cases still had lateral lymph node metastasis.In the L-TME+LLND-B group,there was no significant difference in the rate of lateral lymph node metastasis in the three groups with a cut-off value of ≥5 mm,≥ 8 mm,and ≥ 10 mm.After the propensity score is matched,The operation time of the L-TME+LLND group was333(174-388)min,which was significantly longer than the operation time of the L-TME group 180(150-205)min.The difference between the two groups was statistically significant(P=0.0002).In addition,the former operation The amount of bleeding was 246(112-422)ml,which was significantly more than the amount of bleeding of 100(50-100)ml in the L-TME group.The difference was statistically significant(P=0.002).There was no significant difference in the main indicators of the two groups after surgery.(P>0.05),focusing on many aspects such as catheter indwelling time,first postoperative ventilation time,postoperative hospital stay,total hospitalization cost and so on.In addition,there was no significant difference in the level of tumor differentiation between the two groups(P=0.830).The total number of postoperative lymph node dissections in the L-TME+LLND group was 28.5(15-37),which significantly exceeded the 16(7-31)in the L-TME group,so the difference was very significant(P=0.026);there were 9 cases in the L-TME+LLND group(30%)postoperative pathology reports lateral pelvic lymph node(LPLN)metastasis,5 cases(16.7%)had obturator lymph node metastasis,3(10%)had intrailiac vascular lymph node metastasis,and 1(3.3%)had iliac Lymph node metastases in the external and common iliac vascular areas.For LPLN-positive patients,the rates of lymph node metastasis in the obturator area,internal iliac vascular area,and external iliac area were 55.6%,33.3%,and 11.1%.In the L-TME+LLND group and L-TME group,no patients died within 30 days of the operation.In addition,for the L-TME+LLND group,the complication rate within 30 days after the operation was 26.7%(8/30),and the other group reached 23.3%(7/30),they are not statistically significant(P=0.766).The complications of Clavien Dindo at all levels are not significant,so they are not statistically significant.Conclusion 1.The Laparoscopic TME add LLND is safe and feasible;2.NACRT is not enough to treat LPLN metastasis,it is still necessary to perform LLND after NACRT;2.It is meaningful to perform LLND when the lateral lymph node short diameter≥5mm.