Lymph node yield, survival benefit, and safety of high and low ligation of the inferior mesenteric artery in colorectal cancer surgery: a systematic review and meta-analysis.

PURPOSE: The aim of this meta-analysis was to compare high inferior mesenteric artery (IMA) ligation (HL) with low IMA ligation (LL) for the treatment of colorectal cancer and to evaluate the lymph node yield, survival benefit, and safety of these surgeries. METHODS: PubMed, Embase, Cochrane Library, Web of Science, and China Biomedical Literature Database (CBM) were systematically searched for relevant articles that compared HL and LL for sigmoid or rectal cancer. We calculated the odds ratio (OR) with 95% confidence intervals (CIs) for dichotomous outcomes and the weighted mean difference (WMD) for continuous outcomes. RESULTS: In total, 30 studies were included in this analysis. There were significantly higher odds of anastomotic leakage and urethral dysfunction in patients treated with HL compared to those treated with LL (OR = 1.29; 95% CI = 1.08 to 1.55; OR = 2.45; 95% CI = 1.39 to 4.33, respectively). There were no significant differences between the groups in terms of the total number of harvested lymph nodes, the number of harvested lymph nodes around root of the IMA, local recurrence rate, and operation time. Further, no statistically significant group differences in 5-year overall survival rates and 5-year disease-free survival rates were detected among all patients nor among subgroups of stage II patients and stage III patients, respectively. CONCLUSIONS: LL can achieve equivalent lymph node yield to HL, and both procedures have similar survival benefits. However, LL is associated with a lower incidence of leakage and urethral dysfunction. Thus, LL is recommended for colorectal cancer surgery.

Preservation of left colic artery with lymph node dissection of IMA root during laparoscopic surgery for rectosigmoid cancer. Results of a retrospective analysis.

BACKGROUND: During sigmoid or rectal cancer surgery, dissection of lymph-nodes at the origin of inferior mesenteric artery is mandatory. Nevertheless, ligation of the origin of IMA should compromise blood supply to left colon and affect anastomosis. The aim of this retrospective evaluation is to compare high IMA ligation and low IMA ligation with preservation of LCA and skeletonization of the origin of IMA during laparoscopic colorectal resection. METHODS: All 120 patients included were affected by clinically M-0 sigmoid or rectal cancer. A laparoscopic colorectal resection with low or high ligature of IMA was performed. Low ligation was carried out with lymphadenectomy of the arterial root. Patients were divided in 2 groups according to type of treatment: Group A, high IMA ligation (N=65), Group B, low ligation with lymphadenectomy of IMA root (N=55). RESULTS: Preoperatively 59 patients had stage I, 42 patients had stage II  and 19 patients had stage III tumor. A mean of 20.3 +/- 4.5 lymph nodes were removed in group A patients and 18.9 +/- 9.1 in group B patients, and this difference was not statistically significant. Operative time, intraoperative and postoperative complication rates were not different between the two group. CONCLUSIONS: Low IMA ligation combined with lymph-node dissection at its origin is safe and effective, not time consuming and not associated to increased risk of complications and nerve damage. This technique can be considered as alternative to standard high IMA ligation in selected patients.