A Novel Noninvasive Method for Predicting Liver Fibrosis by Quantifying the Estrangement of Indocyanine Green Retention Rate and Tc-99m-diethylenetriamine-penta-acetic Acid-galactosyl Human Serum Albumin Scintigraphy

Background/Aim: Indocyanine green (ICG) clearance test is one of the most popular dynamic methods for evaluating preoperative liver function to avoid posthepatectomy liver failure (PHLF). Tc-99m-diethylenetriamine-penta-acetic acid-galactosyl human serum albumin scintigraphy (GSA) also facilitates the direct estimation of functional hepatocytes and can estimate the ICG retention rate (R15); however, in some cases, there is a discrepancy between results of a preoperative examination of ICG-R15 and the estimated ICG-R15 obtained by 99mTc-GSA (GSA-R15). This study evaluated the gap between ICG-R15 and GSA-R15 (ΔICG) for predicting background liver fibrosis in patients who underwent hepatectomy. Patients and Methods: Sixty-four consecutive patients who underwent hepatectomy and preoperative ICG-R15 and GSA-R15 examinations from 2016 to 2019 were retrospectively evaluated. The gap between GSA-R15 and ICG-R15 was defined as ΔICG and the factors predicting liver fibrosis were investigated. Results: In the pathologically-proven cirrhotic group, platelet counts were significantly lower and ΔICG values were significantly larger than those in the non-/early-cirrhotic group. A multivariate analysis identified a higher total bilirubin level, a higher AST level, and a larger ΔICG level as significant predictive factors for liver cirrhosis. Conclusion: Larger ΔICG was found to be an independent preoperative predictor of liver fibrosis and may positively contribute to decision-making before hepatectomy to avoid PHLF.