A Radiological and Pathological Assessment of Ileocolic Pedicle Length As a Predictor of Lymph Node Retrieval Following Right Hemicolectomy for Caecal Cancer

Background: In colon cancer, the number of harvested lymph nodes is critical for pathological staging. It has been proposed that the more central the mesenteric vascular ligation, the greater the nodal yield. The aim of the current study was to determine the association of radiological and pathological ileocolic pedicle length on nodal harvest following right hemicolectomy for caecal cancer.

Methods: A series of 50 patients undergoing right hemicolectomy for adenocarcinoma underwent specimen evaluation. Preoperative computed tomography images were reconstructed and analysed to determine the direct (vessel origin to caecum) ileocolic pedicle length.

Results: The median pathological distance from the tumour to the high vascular tie was 80 mm, and median nodal yield was 16.5 nodes. Radiological pedicle length did not correlate with the pathological distance from the tumour to the high vascular tie or nodal yield; however, the pathological pedicle length did correlate with the total nodal yield (r (2): 0.343, p = 0.015). The median pathologically determined length of colon resected (r (2): 0.153, p = 0.289), ileum resected (r (2): 0.087, p = 0.568) and total specimen length resected (r (2): 0.182, p = 0.205) did not correlate with the total nodal yield. An ileal specimen length ≤25 mm [hazard ratio (HR) 14.8, 95 % confidence interval (CI) 1.1-194.5, p = 0.040] and a well-differentiated tumour (HR 10.5, 95 % CI 1.1-95.9, p = 0.037) increased the likelihood of retrieving <12 lymph nodes.

Conclusions: Based on these data, pathologic pedicle length is a determining factor in lymph node retrieval. Preoperative radiological calculation of pedicle length does not help predict the number of lymph nodes retrieved.