Intraoperative fluorescence imaging with indocyanine green in hepatic resection for malignancy: a systematic review and meta-analysis of diagnostic test accuracy studies.

BACKGROUND: Fluorescence imaging during hepatic resection has the potential to identify additional malignant tumors, increasing the chance for complete tumor resection. Indocyanine green (ICG) is an FDA approved, fluorescent dye used in a variety of surgical procedures. The objective of this study was to define the sensitivity of intraoperative ICG fluorescent imaging in the detection of hepatic malignancy in adult patients during hepatic resection, which was accomplished by performing a systematic review and meta-analysis. METHODS: The databases Medline, EMBASE, Scopus and Web of Science were assessed in September 2018. Article inclusion criteria was (1) Liver resection for malignancy (2) ICG injected pre or intraoperatively (3) Use of infrared electronic endoscopy or near-infrared fluorescence imaging intraoperatively (4) Patient age >/= 18 years (5) N > 5 patients (6) Human and English studies only. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) guidelines were used for quality assessment. Data synthesis was completed using Meta-Disc and MedCalc software. A DerSimonian-Laird random effects model was used for the meta-analysis. RESULTS: 21 studies and 841 patients were included in our systematic review. Seven studies and 319 patients were included in the meta-analysis. The pooled sensitivity of intraoperative ICG fluorescence was 0.75 (0.71-0.79). Sensitivity for superficial tumors ranged from 0.96 to 1.00. Heterogeneity (I(2)) was calculated at 65.1%. ICG-related fluorescence imaging detected new malignant tumors not detected by conventional means in 42 of 362 patients across 13 studies. CONCLUSION: The sensitivity of intraoperative ICG-related imaging for superficial tumors is high; however, overall sensitivity is low, at 0.75, suggesting that it would have to be used in combination with current identification methods such as intraoperative ultrasound. Our study also found that intraoperative ICG fluorescence imaging was able to detect additional malignant hepatic tumors in 11.6% of patients.