A Novel Parameter Identified Using Indocyanine Green Fluorescence Angiography may Contribute to Predicting Anastomotic Leakage in Gastric Cancer Surgery

Background Anastomotic leak is one of the most serious postoperative complications, and intraoperative adequate perfusion plays a key role in preventing its development in gastric cancer surgery. This study aimed to investigate the relationships between anastomotic leak and the parameters defined by an assessment of intraoperative anastomotic perfusion using a near-infrared indocyanine green (ICG) fluorescence system and to evaluate the usefulness of this ICG fluorescence assessment in gastric cancer surgery. Methods We retrospectively reviewed data of 100 patients who underwent gastric cancer surgery. In a visual assessment based on fluorescence intensity, we classified ICG fluorescence image patterns as homogeneous, heterogeneous, or faint. In a chronological assessment, the first or second time point of ICG fluorescence appearance on one or the other side of the anastomosis was defined as FT or ST, respectively. The time difference in ICG fluorescence appearance between FT and ST was defined as TD. The relationships between anastomotic leak and the evaluated clinical factors, including the parameters identified by the ICG fluorescence assessment, were evaluated using univariate or multivariate analysis. Results Although no signs of leak were found by surgeons’ subjective judgments, four patients developed postoperative anastomotic leak of Clavien–Dindo grade III or IV. Multivariate analysis revealed that TD was an independent predictor of anastomotic leak (odds ratio 35.361, 95% confidence interval 1.489–839.923, p = 0.027). Conclusions A novel parameter identified using near-infrared ICG fluorescence assessment may be useful to predict anastomotic leak in gastric cancer surgery. Trial Registration UMIN Clinical Trials Registry: #UMIN000030747 ( https://www.umin.ac.jp/ctr/index.htm ).