Evaluation of Indocyanine Green Fluorescence Imaging for Intraoperative Identification of Liver Malignancy

There is early evidence that indocyanine green (ICG) fluorescence imaging has the ability to detect metastatic and primary malignancies in the liver that are too small to be identified by other methods. However, the rate of false positives and false negatives remains unknown.

This is a single institution prospective single-arm study. Patients with suspected hepatic or pancreatic malignancies were intravenously injected with ICG one to three days prior to their scheduled surgical therapy. At the beginning of the procedure, the liver was assessed with fluorescence imaging and all identified lesions were biopsied and evaluated.

Twenty-three patients were enrolled from April 2015 through February 2016. Fifteen patients with confirmed malignancy had adequate fluorescence imaging evaluation of the liver; 10 with pancreatic primary malignancies and five with hepatic primaries. Fluorescence imaging was the only modality that identified nine concerning hepatic lesions, all of which were benign on pathology examination. Out of 11 malignant hepatic masses, six were visible on fluorescence imaging. Out of nine benign hepatic lesions, five were visible. No side effects or complications of the fluorescence imaging were encountered. The sensitivity for ICG fluorescence was 45.5%, the specificity 21.2%, the positive predictive value 25%, and the negative predictive value 40%.

Intraoperative hepatic assessment with ICG fluorescence imaging to identify malignancy in the liver is feasible and safe. However, in this study the significant number of false positives limit the utility of the technique. Our preliminary data do not support its routine use for detection of malignancies in the liver.