Detection of indocyanine green fluorescence to determine tumor location during laparoscopic gastrectomy for gastric cancer: Results of a prospective study

Abstract

Introduction In laparoscopic gastrectomy, a method to locate the margin of an early‐stage cancerous lesion that is invisible from the serosal surface and impalpable during laparoscopic procedures is needed to determine an appropriate transection line. We conducted a prospective study to develop a new marking method using preoperative submucosal injection of indocyanine green (ICG). Methods Patients undergoing laparoscopic gastrectomy for T1 gastric cancer were recruited. The first 11 patients comprised the learning set and the subsequent 18 patients the validation set. ICG was endoscopically injected in the submucosal layer of the stomach approximately 1 cm away from the tumor edge 1 or 3 days before surgery. The diameters of the visualized ICG were compared with those of a conventional marking method using India ink in 10 historical controls. Results In the learning set, the optimal amount of ICG was determined to be 0.1 mL at a concentration of 0.5 mg/mL. In the validation set, the same procedure was repeated. No technical problems or adverse reactions related to ICG injection were observed. In all cases, ICG was successfully detected, and negative surgical margins were pathologically confirmed. The mean long diameter of the visualized ICG fluorescence measured at the mucosal surface of the stomach was significantly smaller in the current study than in the historical controls in whom India ink was used (21 vs 52 mm, P < 0.0001). Conclusions The preoperative submucosal ICG marking was safely performed and successfully detected without excessive blurring during laparoscopic gastrectomy.

Analysis of safety and efficacy of laparoscopic radical gastrectomy combined with or without indocyanine green tracer fluorescence technique in treatment of gastric cancer: a retrospective cohort study

“…ICG fluorescence laparoscopy has been applied in gastrointestinal surgery in recent years. Several studies have found that, in gastric cancer surgery, preoperative smaller doses of ICG injection in the submucosa around the tumor are conducive to clear imaging of tumor location intraoperatively, and indicate that ICG fluorescence laparoscope could be used to determine the accurate position of intraoperative tumors (18)(19)(20). These studies support the findings of the present study.…”

Preoperative endoscopic marking of the gastrointestinal tract using fluorescence imaging: submucosal indocyanine green tattooing versus a novel fluorescent over-the-scope clip in a survival experimental study

“…This NIR imager produces pictures with a superior fluorescent signal contrast than the imaging system used in our study [27]. Currently, there is no consensus on the ICG concentration required for submucosal GI tattooing and the literature has a large dose variability [13][14][15][16][17][18]. The ICG dosing chosen for our study was the same utilized in the successful work by Ushimaru et al on gastric tumor tattooing [14].…”

“…The main advantage of ICG over non-fluorescent dyes (India ink and SPOT™) is that, in cases of intraperitoneal spillage, the surgical dissection planes are potentially less compromised under white light. For this reason, several authors have recently successfully used ICG as an efficient and safe alternative gastrointestinal tattooing method in clinical trials [13][14][15][16][17][18]. However, in most of those trials, the endoscopic ICG tattooing was performed 1 to 3 days preoperatively which is clinically improbable.…”

“…This has motivated researchers to seek more efficient alternatives. Recently, preoperative endoscopic tattooing of gastric [13,14] and colorectal [15][16][17][18] lesions using indocyanine green (ICG), an exogenous fluorophore visible in real time using near-infrared (NIR) cameras, has been described. ICG is a cyanine dye, which is a brilliant visible green at high concentrations, but remains invisible at lower concentrations.…”

Near-Infrared Fluorescence Image-Guided Surgery in Esophageal and Gastric Cancer Operations

“…Similar results of fluorescent marking with ICG were presented by Ushimaru et al; 16 in a group without ICG injection, a positive resection margin was found in 5% of cases, whereas in a group with ICG tumor position marking, it was found in 0% of cases. Tanaka et al 17 proposed a dosage of 0.1 mL at a concentration of 0.5 mg/mL for optimal visualization of injection sites. Diameters of ICG injection sites were much smaller (i.e., 21 mm) than historical controls with India ink (52 mm).…”