In the evolving landscape of colorectal cancer surgery, a pivotal question has persistently intrigued surgeons and oncologists alike: what is the optimal surgical technique for ligating the inferior mesenteric artery (IMA) during resections for rectal and sigmoid colon cancers? The inferior mesenteric artery, a major vessel supplying blood to the large intestine, plays a crucial role in the success of these operations. A recent meta-analysis published in BMC Cancer sheds new light on this critical aspect, comparing the outcomes of high ligation versus low ligation of the IMA in colorectal cancer surgery. The findings are poised to influence surgical standards and enhance patient recovery protocols globally.
The study rigorously analyzed data across sixteen randomized controlled trials encompassing a cohort of 1778 patients. This comprehensive research effort meticulously compiled evidence from several major medical databases, including PubMed and EMBASE, to ensure robust and up-to-date coverage of the literature until March 2025. The focus was to discern the impact of ligation level on surgical outcomes such as anastomotic leakage, postoperative gastrointestinal recovery, operative blood loss, lymph node harvest, tumor recurrence, and long-term survival metrics.
Ligation of the inferior mesenteric artery traditionally follows two surgical techniques: high ligation at the artery’s root near the aorta and low ligation positioned distally at the origin of the left colic artery. This procedural choice has far-reaching implications, as it determines blood flow preservation to the remaining colon and potentially affects postoperative complications and cancer prognosis. The debate over which method yields better clinical results has persisted, underpinned by conflicting data and varied surgical philosophies.
The meta-analysis’ pivotal revelation is that low ligation significantly reduces the incidence of anastomotic leakage—a complication where the surgical connection between bowel segments leaks intestinal contents. Anastomotic leakage remains a dreaded postoperative complication due to its association with prolonged hospital stays, increased morbidity, and even mortality. The study found that patients undergoing low ligation had less than half the risk of leakage compared to those with high ligation, a statistically and clinically significant finding.
Beyond reducing leakage risk, low ligation demonstrates a pronounced acceleration in postoperative gastrointestinal function recovery. Faster return of bowel movements and improved defecation ease are critical for patient comfort and reducing hospitalization duration. The study quantified this improvement using standardized mean difference measures, confirming that the low ligation technique supports quicker restoration of digestive tract motility without imposing additional risks.
Interestingly, the study also highlights that the choice of ligation level does not significantly impact other important clinical outcomes. Hospital length of stay, intraoperative blood loss, number of lymph nodes harvested for pathological examination, and rates of tumor recurrence were comparable between the two techniques. These findings suggest that low ligation offers protective benefits against certain complications without compromising oncological radicality or surgical safety.
Long-term outcomes, including five-year overall survival and disease-free survival rates, did not differ significantly between high and low ligation groups. This crucial insight reassures clinicians that adopting low ligation techniques does not adversely affect cancer control or patient survival, affirming its viability as a surgical standard. Similarly, concerns regarding urinary retention, urinary incontinence, and sexual dysfunction—a known sequela of pelvic surgeries—were unfounded, with no statistical differences discerned between the techniques.
The implications of these results resonate through the surgical oncology community. The ability to minimize anastomotic leakage holds immense importance, not just for immediate postoperative recovery but also for influencing long-term outcomes positively. Leakage episodes have been associated with higher local recurrence rates and impaired patient quality of life. Thus, the demonstrated advantage of low ligation could translate into improved cancer survivorship and reduced healthcare burdens.
Anatomical and physiological considerations underlie these findings. High ligation involves ligating the IMA at its origin, which disrupts blood flow more proximally and may compromise perfusion to the anastomotic site, predisposing to ischemia and leakage. Conversely, low ligation preserves the left colic artery, which maintains collateral circulation and enhances blood supply to the downstream colon. This preservation likely explains lower leakage rates and improved bowel function observed with the low ligation strategy.
While low ligation’s surgical technique may be perceived as more challenging due to intricate vascular anatomy and the need for precise dissection near the left colic artery, the long-term benefits justify the expertise required. Training programs and surgical guidelines should emphasize anatomical mastery to optimize patient outcomes. Moreover, the study encourages reappraisal of existing protocols favoring high ligation in certain centers that may have prioritized technical simplicity over patient-centric outcomes.
The meta-analysis’ methodological strength lies in its inclusion of randomized controlled trials, providing the highest level of clinical evidence in surgical research. The use of validated tools like AMSTAR-2 for assessing the quality of systematic reviews ensures that conclusions are drawn from reliable and unbiased data. Nonetheless, the authors acknowledge heterogeneity among trials regarding surgical expertise, patient selection, and postoperative care protocols, calling for standardized approaches in future studies.
Further research directions could explore the molecular and microvascular effects of differing ligation levels, providing insights into the biological mechanisms underpinning surgical outcomes. Evaluating patient-reported outcomes and cost-effectiveness analyses would also enrich the evidence base, enabling healthcare systems to adopt best practices aligned with both clinical efficacy and economic sustainability.
In conclusion, this landmark meta-analysis compellingly advocates for low ligation of the inferior mesenteric artery during rectal and sigmoid colon cancer surgeries. The procedure emerges not only as a safer option with reduced anastomotic leakage but also facilitates quicker gastrointestinal recovery without compromising oncological safety or patient quality of life. As colorectal cancer remains a global health challenge, refinement in surgical techniques such as this can significantly impact patient outcomes and optimize therapeutic strategies in oncology.
Subject of Research: Surgical outcomes of inferior mesenteric artery ligation levels in rectal and sigmoid colon cancer
Article Title: The surgical effect of inferior mesenteric artery ligation level in rectal cancer and sigmoid colon cancer: a meta-analysis of randomized controlled trials
Article References:
You, JH., Deng, YB., Li, YB. et al. The surgical effect of inferior mesenteric artery ligation level in rectal cancer and sigmoid colon cancer: a meta-analysis of randomized controlled trials. BMC Cancer 25, 1531 (2025). https://doi.org/10.1186/s12885-025-14959-3
Image Credits: Scienmag.com
DOI: https://doi.org/10.1186/s12885-025-14959-3
Tags: anastomotic leakage in colorectal surgerycolorectal cancer surgical outcomeshigh vs low ligation in colon cancerimpact of blood supply on colon surgeryinferior mesenteric artery ligation techniqueslong-term survival after colon cancer surgerylymph node harvest in colorectal resectionsmeta-analysis of colorectal cancer resectionspostoperative recovery in colon cancerrandomized controlled trials in cancer surgerysurgical standards in colorectal cancertumor recurrence in colorectal cancer
