Propensity-score-matched analysis of short- and long-term outcomes in patients with an ileocolic artery crossing anterior vs posterior to the superior mesenteric vein during curative resection for right-sided colon cancer.

BACKGROUND

Colorectal cancer is one of the most common malignant diseases worldwide. However, laparoscopic lymph node dissection is technically demanding and time-consuming in right-sided colon cancer surgery because of variable vessel anatomy. We evaluated whether the ileocolic artery (ICA) crossing anterior to the superior mesenteric vein (SMV) was associated with better intraoperative parameters and survival compared with the ICA crossing posterior to the SMV, following laparoscopic curative resection for right-sided colon cancer.

METHODS

This was a propensity-score-matched retrospective study including data for 540 patients with right-sided colon cancer undergoing laparoscopic curative resection (299 with the ICA crossing anterior to the SMV (group A) and 241 with the ICA crossing posterior to the SMV (group B). We compared propensity-matched scores between the two groups to evaluate surgical and oncological outcomes.

RESULTS

We found no significant difference in 5-year overall survival rates between groups for any disease stage (0-III). However, 5-year disease-free survival (DFS) rates did differ significantly between groups (p = 0.011), especially in patients with stage III disease (p = 0.013). We then performed univariate and multivariate analyses to determine the associations between DFS and ICA location and tumor-node-metastasis (UICC) stage. ICA location and UICC stage had a poor association with DFS on univariate analysis: ICA hazard ratio (HR) 2.52, CI 1.19-5.78, p = 0.014 vs HR 3.18, CI 1.08-9.46, p = 0.03, and on multivariate analysis: HR 2.48, CI 1.17-5.69, p = 0.016 vs HR 3.86, CI 1.90-7.96, p = 0.0002.

CONCLUSION

Our results showed that an ICA crossing posterior to the SMV was associated with worse DFS compared with an ICA crossing anterior to the SMV. We recommend careful laparoscopic technique in patients with an ICA crossing posterior to the SMV, during lymph node resection in right-sided colon cancer surgery.