In recent years, the incidence of fatty liver caused by alcohol consumption, the metabolic syndrome, NAFLD, and non-alcoholic steatohepatitis (NASH) has increased. Additionally, the administration of irinotecan-based chemotherapeutic regimens for colorectal cancer has been shown to correlate with the development of steatohepatitis, [11–12] and it increases the need for hepatectomy to remove the metastatic carcinoma from steatotic livers. The influence of steatosis following resection of fatty liver tissue remains uncertain, despite numerous reports.
In clinical practice, elevated serum transaminase and TB levels, decreased PT, and decreased PLT count of the peak value rates are used to estimate the approximate surgical damage to the liver. Elevated serum transaminase indicates the volume of hepatocytes that were impaired during surgery, and the changes in the TB level and PT are considered to have a significant effect on liver regeneration. In this study, AST and the ALT elevation rate after hepatectomy were significantly higher in patients with viral hepatitis, and there was no significant difference between patients with steatohepatitis and steatosis. Postoperative transitions in the TB and Alb levels and the PT did not differ between the groups, and there were no significant differences in the postoperative complications and hospital stay length between the groups.
Although the transaminase level showed the most noticeable changes, ALT elevation correlated with a longer Pringle time and lower preoperative liver stiffness, and was not related to the degree of steatosis. The negative correlation between the liver stiffness value and the ALT value is consistent with a previous report that postoperative transaminase elevation was uncommon in patients with cirrhosis. Sugiyama et al. reported that a cirrhotic remnant liver, including one with marked fibrosis, may release smaller amounts of aminotransferase as compared to normal livers after warm ischemia-reperfusion (IR).  They observed the presence of collateral circulation and suggested that the absence of portal congestion in patients with cirrhotic livers may explain the improved tolerance to the Pringle maneuver. There were no differences in the postoperative course, including the complication rate, post-hepatectomy liver failure rate,  and length of hospital stay after surgery between patients with viral hepatitis, steatosis, and steatohepatitis.
However, hepatic steatosis is reported to be a risk factor for postoperative graft dysfunction in transplantation. [2, 15] In cases of transplantation, macrovesicular steatosis affecting more than 30% of the hepatocytes which is thought to be associated with the metabolic syndrome and alcohol abuse, was reported to be associated with an increased risk of primary graft dysfunction and graft loss due to IR injury. [2–3, 5, 15, 17–18] Macrovesicular steatosis, which is characterized by intracellular lipid accumulation and increases in the hepatocyte volume, leads to obstruction of the adjacent sinusoid spaces, and increasing vascular resistance in the hepatic microcirculation leads to mitochondrial dysfunction during reperfusion. [16, 19–20]
Generally cold IR ins used in transplantation, while warm IR is used in hepatectomy. There are fundamental differences between warm and cold IR. Warm IR injury is caused by inflow occlusion during transection of the liver and damages the hepatocytes, while cold IR injury damages liver the sinusoidal endothelial cells (LSEC). [21–23] Some studies have reported that liver regeneration requires increased expression of the hepatocyte growth factor by the LSECs and increased LSEC proliferation. [4, 24–25] Therefore, liver regeneration is suppressed by cold IR.
Most patients in this study had serum blood test abnormalities, which improved to normal ranges by the fifth or seventh postoperative day. They were discharged without significant postoperative complications, long-term hospital admission, or death from postoperative liver failure.
This study was not without limitations. The number of hepatectomies performed in patients with cirrhosis was small and the Pringle time seemed to have been short. Thus, it is necessary to perform further studies to determine both the effects of hepatectomy on fatty liver and to determine the volume of tissue that can be safely excised from patients with fatty liver.