Limited Excised Functional Liver Tissue in Hepatectomy for Large Hepatic Tumors Proved by a Three-Dimensional Reconstruction Technique

Abstract

Three-dimensional (3D) reconstruction techniques have been widely used in the preoperative evaluation of hepatectomy. Here we used a 3D reconstruction technique to estimate the remnant liver volume and clarify a clinical speculation that limited functional liver tissue would be excised in hepatectomy for large hepatic tumors. Hepatectomy simulation by IQQA-Liver software was applied to 108 patients of hemihepatectomy divided into two groups (tumor diameter ≥ 10 cm vs.<10 cm). Liver volume (LV), standard liver volume (SLV), tumor volume (TV), functional liver volume (FLV), excised liver volume (ELV), excised functional liver volume (EFLV) and residual liver volume (RLV) were measured. Then we compared the rate of total liver resection (ELV/LV), the rate of functional liver resection (EFLV/FLV), and the relative rate of future liver remnant (RLV/FLV and RLV/SLV) between the two groups. The ELV calculated by the 3D reconstruction procedure were highly consistent with the actual liver excised volume (r=0.994, p<0.001), showing the accuracy of the simulation. Significantly smaller EFLV/FLV was seen in patients with a tumor diameter ≥ 10 cm than in patients with a tumor diameter<10 cm (p<0.01), in both the right and left hemihepatectomy subgroup. In contrast, significantly larger RLV/FLV was seen (p<0.01), and there was no difference of the RLV/SLV (p>0.05). Twenty-five patients had RLV/LV<30%, a recognized ratio of future liver remnant for safe hepatectomy. However, only one patient had RLV/SLV<30%. 97.2% of the patients had RLV/FLV>40%, and 98.1% had RLV/SLV>40%, accounting for the overwhelming majority of all patients. There was no hepatic failure or death within 30 days of surgery. In summary, it is better to use a 3D reconstruction method for preoperative safety assessment of liver resection for large hepatic tumors, through the hepatectomy simulation and volume calculation. In the same range of anatomical hepatectomy, a larger tumor mass meant less excised functional liver volume and more remnant liver volume. Our results indicated that neither ELV nor RLV/LV, but RLV/SLV was the better determinant of safety of hepatectomy.