OBJECTIVETo explore the safety and feasibility of the combined medial and caudal approach in laparoscopic D3 lymphadenectomy plus complete mesocolic excision(CME) for right hemicolectomy in the treatment of right hemicolon cancer complicated with incomplete ileus.

METHODSClinical data of 65 patients with incomplete obstructive right-sided colon cancer (T1 to 4M0) diagnosed by abdominal CT enhanced scan or MRI and/or electric colonscope undergoing laparoscopic right hemicolectomy (D3 lymphadenectomy + CME) at Department of Emergency Medicine and Department of Gastrointestinal Surgery from June 2014 to June 2017 were retrospectively analyzed. Among them, 33 patients received the combined medial and caudal approach (combined medial and caudal approach group) and the other 32 patients received the cephalo medial-to-lateral approach (cephalo medial-to-lateral approach group). The operation highlights of the combined medial and caudal approach group were as follows: (1) The superior mesenteric vein (SMV) was first identified and exposed using the combined medial and caudal approach, and lymph node dissection along the anterior and right of SMV was performed. (2) With horizontal part of duodenum as landmarks, the dorsal mesenteric membrane of terminal ileum was opened by caudal-to-cranial approach, and right retroperitoneal space along the Toldt's space was separated. The anterior of pancreatic head and the right Toldt's space were then exposed. (3) Finally using medial-to-lateral approach, the roots of ileocolic vessels, middle colic vessel and right colic vessel were disconnected and ligated along the left border of SMV. The right branch of gastrocolic trunk of Henle was ligated and lymph node dissection along SMV was performed again. Patients in cephalo medial-to-lateral approach group underwent conventional operation. Baseline information, intraoperative blood loss, operation time, number of harvested lymph nodes, proportion of no less than 12 harvested lymph nodes per case, postoperative hospital stay and postoperative morbidity in both groups were analyzed and compared.

RESULTSThirty-eight males and 27 females with age of 31 to 72 (56.8±11.7) years were enrolled in this study. There was no significant difference in baseline information between combined medial and caudal approach group and cephalo medial-to-lateral approach group(all P>0.05). Intraoperative blood loss [(106.5±24.5) ml vs. (308.4±27.1) ml, t=-31.501, P=0.000] was significantly less, and operative time [(176.3 ± 18.0) minutes vs. (208.4 ± 47.3) minutes, t=-3.602, P=0.001] was significantly shorter in the combined medial and caudal approach group. The proportion of no less than 2 harvested lymph nodes per case [87.9%(29/33) vs. 84.4%(27/32)], the number of harvested lymph nodes (22.5±8.9 vs. 21.5± 7.6), postoperative morbidity of complication [6.1%(2/33) vs. 12.5%(4/32)] and postoperative hospital stay [(11.9±1.5) days vs. (13.4±4.4) days] were not significantly different between the two groups(all P>0.05).

CONCLUSIONThe combined medial and caudal approach in laparoscopic right hemicolectomy (D3+CME) in the treatment of incomplete obstructive right-sided colon cancer is safe and feasible, and has advantages of less intraoperative blood loss and shorter operation time compared to the cephalo medial-to-lateral approach.