How Much Dissection Is Enough? Mesenteric Vessel Skeletonization Length and Lymph Node Harvest Quality in Rectal...

BackgroundAdequate lymph node retrieval is essential for rectal cancer staging, but the quantitative association between inferior mesenteric artery (IMA) vascular pedicle skeletonization and harvest quality remains unclear. This study assessed that association during laparoscopic total mesorectal excision.MethodsThis single-center retrospective study included 299 patients with middle or low rectal adenocarcinoma who underwent laparoscopic radical resection from January 2021 to March 2025. Skeletonization length was measured from operative videos. Patients were divided into high (≥5.2 cm; n = 150) and low (<5.2 cm; n = 149) skeletonization groups. Multivariable regression and receiver operating characteristic analyses were performed.ResultsThe high skeletonization group had more retrieved lymph nodes [18 (14-23) vs 14 (11-17)] and higher rates of retrieval of ≥12 nodes (94.0% vs 79.2%) and ≥1 No. 253 lymph node (89.3% vs 65.8%; all P < 0.001). Skeletonization length was independently associated with total lymph node yield (standardized β = 0.398, P < 0.001) and retrieval of ≥12 nodes (OR = 1.785, 95% CI: 1.426-2.234). The area under the curve was 0.768, with an exploratory cutoff of 4.8 cm. High skeletonization increased operative time by 16.2 minutes without increasing postoperative complications.ConclusionGreater IMA vascular pedicle skeletonization length was associated with improved lymph node harvest quality without increased short-term morbidity, although operative time was longer. The 4.8-cm cutoff requires external validation.