Safe D3 Right Hemicolectomy for Cancer Through Multidetector Computed Tomography (MDCT) Angio

Overview

When performing a resection of the right colon due to cancer one aims not only to remove the tumor bearing bowel segment, but also lymph nodes draining the affected area. These lymph nodes are located along the arteries supplying the right colon. Through using a preoperative CT scan which can map these arteries very precisely one can ligate these vessels closer to their origin and thus remove more lymph nodes which may potentially harbor cancer cells. This study aims to compare patients operated more radically through use of preoperative CT which maps the mentioned arteries with patients operated in the standard way.

The Norwegian gastrointestinal cancer group has recommended D3 resection as the standard operative technique for colon cancer. D3 resection implies ligation of the blood vessels at their origin. There is evidence that the recurrence free period and survival improves with the number of lymph nodes harvested at surgery. However, the current practice in Norway, while performing right hemicolectomy for cancer is to ligate the feeding vessels for the right colon on the right hand side of the superior mesenteric vein (SMV). Significant arterial stumps have been demonstrated in patients operated for right colon cancer with this technique (right colic artery and ileocolic artery vascular stumps with an average length of 3.5 cm and 2.5 cm, respectively). This leaves reason to believe that a certain number of central lymph nodes remain after the procedure. The complex anatomical relationship between the right colic artery and ileocolic artery with the superior mesenteric vein make D3 resection demanding, especially if the right colic artery lies posterior to the SMV. These relationships are investigated in detail in postmortem anatomical studies. These studies show that the right colic artery lies most often anterior to the SMV, while the ileocolic artery lies most often posterior to the SMV. Data has also been provided that a CT angiography can verify these relations as well as postmortem anatomical studies in living patients, thus allowing the surgeon to be aware of them prior to surgery. This could prove to be crucial in planning the procedure.