Identification of mesenteric lymph nodes in robotic complete mesocolic excision by near-infrared fluorescence imaging.

Abstract

One of the most important prognostic factors in colorectal cancer is nodal status at the time of surgical treatment. Complete mesocolic excision (CME) with central vascular ligation, which follows similar oncologic principles to total mesorectal excision, has revolutionized the surgical treatment of colon cancer, showing a higher degree of lymphadenectomy and better oncologic outcomes compared to standard colectomy [1]. The rationale behind this technique is to remove the entire mesocolon and all potential routes of lymphatic spread by dissecting along embryologic tissue planes and transecting the supplying vessels at their origin [1, 2]. Since 2001, surgical treatment for colorectal cancer has seen another substantial development due to the introduction of robotic technology [3]. Thanks to its potential for overcoming the limitations of standard laparoscopy, the robotic approach is increasingly being employed in colorectal surgery. Recently, the technical feasibility and safety of robotic surgery in the CME technique for right colon cancer also has been reported [4]. Although CME is now the technique for optimal clearance of lymph nodes, a more sophisticated capability to visualize the actual lymphatic drainage from the tumor site into the colonic mesentery may further maximize nodal harvest in CME. This may also be of use in the determination of a suitable mesentery division line, especially in obese patients with excessive mesenteric adipose tissue. The near-infrared fluorescence imaging (NIFI) system has been developed for this type of navigation surgery, and now, this system is also available in robotic technology. The utility of NIFI has been previously reported in various colorectal procedures [5–7], but its role in the identification of both the lymphatic flow distribution and lymphatic basin in robotic CME has not been described. Here, we present a video to demonstrate intraoperative lymph node identification in an obese patient undergoing robotic CME for cecal adenocarcinoma. The patient was a 76-year-old female with a body mass index of 39.6 kg/m. One day before surgery, indocyanine green (ICG) solution was injected via colonoscopy into the submucosa in four quadrants around the lesion; 0.5 ml of ICG (2.5 mg/ml) was delivered with each injection. Intraoperatively, the da Vinci Xi Firefly NIFI system (Intuitive Surgical Inc., Sunnyvale, CA, USA) was used to assess lymphatic flow distribution from the colonic wall into its mesentery. The lymphatic ducts and lymph nodes were clearly visualized in real time, and this proved useful in choosing the extent of mesenteric dissection. No complications occurred during surgery. Total operative time was 395 min, and blood loss was 100 ml. The patient did not show any adverse reaction to the ICG injection and was discharged home on postoperative day 5 following an uneventful recovery; histopathologic examination revealed a T3 tumor. The total number of harvested lymph nodes was 25, none of which were metastatic (pT3N0M0). Electronic supplementary material The online version of this article (doi:10.1007/s10151-015-1413-3) contains supplementary material, which is available to authorized users.