Experimental Study About The Feasibility Of Hepatectomy Combined With Hepatic Artery Resection

【Objective】Hilar cholangiocarcinoma(HCC),arising from bile duct epithelium and commonly occurs in the main bile duct or at the bile duct confluence,is a rare malignant tumor with a poor prognosis.Surgery remains the only treatment to prolong survival.With advances in surgical techniques,the number of curative resection for HCC has increased.Resectional surgery offers a curative intent and a survival benefit for patients with HCC.In the present, extended partial hepatectomy(PH) for HCC is required to achieve adequate safety margins and become tendency.The patients suffering HCC present obstructive jaundice mostly and often have advanced disease.Under the condition of conspicuous bilirubinemia,patient operated extended hepatic resection associated with high morbidity.So,some scholars suggest that preoperative biliary drainage should be practiced on patients with obstructive jaundice.But in patients with malignant biliary obstruction,preoperative biliary tract manipulation and drainage has been associated with increased infectious complications and mortality.Thus,controversy exists as to whether selective biliary duct drainage is preferable as a preoperative procedure before extended hemihepatectomy for HCC, especially with regard to the functional reserve of the future remnant liver.Due to the central anatomic localization within the liver hilum and special biology behavior characteristics,HCC invade hepatic artery mostly.Recently,hepatic artery resection(HAR) as a aggressive surgical method for HCC has become hot issue and evoked extensive contention in academic circles.Controversies surrounding the issues of HAR for HCC focus on complications and patient's safety after operation.To better understand the mechanism,we designed the animal model to study influence about liver function,hepatic energy metabolism,liver regeneration and hepatocye apoptosis on the SD rats with obstructive jaundice after PH combined with HAR and internal biliary drainage. 【Methods】The rcsearch includcs two parts.In the first part,we studied that the influence of hepatic extrahepatic collaterals rescction on normal rat.41 male SD rats divided rankly into three groups.6 male SD rats were established as sham operation group.10 male SD rats underwent hepatic artery resection;Other 25 male SD rats underwent hepatic artery and extrahepatic collaterals resection.Levels of TB,ALT,ALB and ALP in serum were dynamic detected in 24h,72h,and 7d after operation.Mortality was calculated.In the secondary part of research,246 male SD rats were in research.6 male SD rats were established as sham operation group.40 male SD rats underwent bridge between common bile duct and duodenum after 70%PH with HAR or 70%PH,and 200 male SD rats which underwent common bile duct ligation(CBDL) for 5 days were randomized into five groups:reperfusion of bile flow(BDO-RBF) group;the 42%PH with bile duct obstruction combined with BDO-RBF group;the 70%PH with BDO-RBF group;42%PH with HAR and BDO-RBF group or 70%PH with HAR and BDO-RBF group.Levels of TB,ALT,ALB and ALP in serum;HGF,bcl-2 mRNA and protein;ATP,ADP and AMP in hepatic tissues;hepatocyte proliferation/ apoptosis index were dynamic observed after operation(24h,72h and 7d) respectively.Mortality was calculated.【Results】There were high mortality in group of rats operated hepatic artery and extrahepatic collaterals resection,and whose liver function did not recovery until 7d after operation.In contrast,benefiting from rapid recovery of liver function after operation,survival rate was excellent in HAR group.Rats without obstructive jaundice would have an excellent liver regeneration after 70%PH.Combined with internal biliary drainage(IBD),the liver function and hepatocyte energy metabolism;condition of HGF,bcl-2 mRNA content of liver tissue and the hepatocyte proliferation/apoptosis index in partial(42%or 70%) hepatectomy and 42% PH with HAR group were greatly influenced while recovered rapidly(P＜0.05). Compared with other groups,the liver function;HGF,bcl-2 mRNA content of liver tissue and the hepatocyte proliferation/apoptosis index in 70%PH with HAR and IBD group were aggravated and has had a significantly increased mortality on obstructive jaundice rats(P＜0.05). 【Conclusions】1.Liver ischemia induced by HAR can be compensated by extra blood supply through extrahepatic collaterals.This phenomenon demonstrates that extrahepatic collaterals play an important physiological role in maintaining liver function.2.Under the condition of conspicuous bilirubinemia,the influence of hepatectomy combined with internal biliary drainage on liver hepatocyte energy metabolism,liver function,liver regeneration and hepatocyte apoptosis is severer than that of normal rats operated 70%PH,while also did the rats recovered rapidly in conspicuous bilirubinemia groups.The database suggested that it was not necessarily the case to operate preoperative external biliary drainage when performing hepatic resection.3.The liver regeneration and hepatocyte apoptosis were not significantly influenced on normal rats operated 70%PH and 70%PH with HAR,moreover,hepatocyte energy metabolism and liver function recovered rapidly in both groups.While it was influenced by conspicuous bilirubinemia in obstructive jaundice rats which operated PH or PH combined with HAR.4.Under the condition of conspicuous bilirubinemia,the influence of 70%PH with HAP,on hepatocyte energy metabolism,liver regeneration and apoptosis is severer than its counterpart of 42%in obstructive jaundice rats.Thus,the later was feasible but the former was not safe in spite of decline preoperative bilirubin.