Laparoscopic middle colic artery-preserved right hemicolectomy with true D3 lymph node dissection for right-sided colon cancer: modified complete mesocolic excision.

Abstract

Complete mesocolic excision (CME) has been demonstrated to be a useful surgical procedure for advanced colon cancer. We previously reported on laparoscopic (Lap) CME with true central vascular ligation (CVL) for advanced right-sided colon cancer. Lap CME with true CVL is highly plausible from the perspective of surgical oncology. However, true CVL of the middle colic artery (MCA) may require extensive resection of the transverse colon. The Japanese Classification of Colorectal Cancer defines D3 as main lymph node dissection around the superior mesenteric artery (SMA), and true CVL is not listed as a required condition. Our institution has been performing a Lap procedure (Lap D3/modified CME) that consists of the dissection of main lymph nodes around the root of the MCA (#223LNs) while preserving the left branch of the MCA. Two videos of a Lap D3/modified CME are presented, and the short-term outcome is reported. Lap D3/modified CME was defined as Lap ligation surgery at the root of the right branch of the MCA that preserves the MCA with #223LNs on the resection side. The present study retrospectively examined 11 cases of Lap D3/modified CME performed at the Tokyo Medical University Hospital between 2015 and 2020. When the SMA is difficult to visualize in Type V/A cases, the SMV is pulled using some silicone string, and the surrounding lymph nodes are dissected while visualizing the SMA. The median operating time was 289min, and the median blood loss was 57ml. The median total number of dissected lymph nodes was 38, and the median number of dissected #223LNs was three. No metastasis was found in the dissected #223LNs. Although this surgery can be performed safely, we believe that this surgery needs to be performed for suitable cases by a highly experienced and skilled surgical team.