Selective central vascular ligation (D3 lymphadenectomy) in patients undergoing minimally invasive complete mesocolic excision for colon cancer: optimizing the risk-benefit equation

Abstract

Aim: Complete mesocolic excision (CME) with central vascular ligation (CVL) has been advocated for right colon adenocarcinoma (RC), but the radicality of vascular dissection remains controversial. Our aim is to report outcomes of selective CVL (D3 lymphadenectomy) during minimally invasive CME for RC.

Method: A prospective database identified patients who were treated for RC between 2009 and 2016. Minimally invasive CME was standard. The radicality of lymphadenectomy was defined as high ligation (HL) versus CVL based on operative reports and videos. Two blinded radiologists independently evaluated the pre- and postoperative CT scans for radiographically abnormal nodes.

Results: Of 197 patients who underwent CME, HL was performed in 56 (28%) and CVL in 141 (72%). There were no baseline differences in age, sex, body mass index, American Society of Anesthesiologists score or pathological staging, and there were no major intra-operative complications in either group (including no major vascular injuries). The median total number of nodes retrieved was 27 and 31 (P = 0.011) in HL and CVL groups, resepctively, with pathologically positive nodes identified in 33.9% and 39.8% (P = 0.704), respectively. Preoperative imaging identified abnormal cN3 nodes in 1.5% of patients; all of whom underwent CVL. No abnormal cN2 or cN3 nodes remained on postoperative imaging. The 60-day mortality was 0.5%, and major morbidity was 4%. One patient (0.5%) had an anastomotic recurrence after a median follow-up of 22 months.

Conclusion: With imperfect preoperative clinical nodal staging, and in the absence of randomized data, the low morbidity and oncological outcomes observed support the approach of CME with HL as a minimum standard, with CVL (D3 lymphadenectomy) in selected cases.

Keywords: CME; D3; central vascular ligation; complete mesocolic excision; lymph nodes; lymphadenectomy.