Assessment of hepatic reserve for indication of hepatic resection: decision tree incorporating indocyanine green test

Preoperative assessment of liver function and prediction of postoperative remaining functional liver parenchymal mass and reserve is of paramount importance to minimize surgical risk, especially in patients with hepatocellular carcinoma (HCC), the majority of whom have liver cirrhosis as a complication. We have established a decision tree for deciding the safe limit of hepatectomy based on three variables: whether ascites is present, the serum total bilirubin level, and the indocyanine green retention rate at 15 minutes (ICGR-15), an indicator of sinusoidal capillarization. In patients who show a sign of decompensated cirrhosis as reflected by an elevated bilirubin value or uncontrollable ascites, hepatectomy is not indicated. In patients without ascites and with normal bilirubin level, the ICGR-15 value becomes the main determinant for the resectability and hepatectomy procedure. Incorporation of ICGR-15 into the decision tree enables patients conventionally classified into Child-Turcotte-Pugh class A or score 5-6 to be subdivided into several groups in which various hepatectomy procedures are feasible: enucleation, limited resection, segmentectomy, mono- to bisectoriectomy, and trisectriectomy. During strict application of this decision tree to 1429 consecutive hepatectomies, of which 685 were performed on HCC patients, during the last 10 years, we encountered only a single mortality.