Choice Of Preoperative Biliary Drainage For Resectable Hilar Cholangiocarcinoma

BACKGROUND Hilar cholangiocarcinoma(HCC)was first recognized by Klatskin on a series of 13 patients in 1965,so it is also known as Klatskin tumor.It is a kind of rare malignant tumor located at the junction of the left and right hepatic ducts.The incidence of hilar cholangiocarcinoma is significantly higher in the eastern countries than the western countries,especially in Thailand,where its incidence is about 90 per 100,000.The hilar cholangiocarcinoma is a kind of mucinous adenocarcinoma,which can be divided into two types,sclerotic or nodular one.It invades the surrounding tissues and thus leads to bile duct stricture,and then the specific clinical symptoms start to appear.Patients often come to see a doctor for painless obstructive jaundice.Radical resection is considered the only treatment of Klatskin tumor for curative intent.However,intrahepatic cholestasis caused by long-term biliary obstruction and a series of pathophysiological changes,including liver dysfunction,coagulation abnormalities,the depressed immune function,malnutrition,the decreased blood flow volume of portal vein system,are bound to pose challenges for surgical resection,for example,increasing the morbidity and mortality after the surgery.Preoperative biliary drainage(PBD),including percutaneous transhepatic biliary drainage(PTBD)and endoscopic biliary drainage(EBD),is proposed to build a safer surgical environment,which could improve the nutritional status,liver function,immunity and the regeneration capacity of liver after the surgery.For those who suffer from severe obstructive jaundice should undergo preoperative biliary drainage to control the risk of the surgery.However,which method of PBD is the optimal solution still remains disputable.OBJECTIVE This article intends to search published literatures systematically to extract information about patients with resectable hilar cholangiocarcinoma undergoing preoperative PTBD or EBD,and then to evaluate their advantages and disadvantages respectively by statistical analysis,providing the optimal methods of PBD for patients who are suffering from severe obstructive jaundice and scheduled to perform the surgery.METHODS A systematic literature research was conducted in CNKI,Wanfang Data,CBMdisc,PubMed,Embase and the Cochrane Library to identify relevant literatures published before October 1st,2019.A systematic review and meta-analysis were then performed.RESULTS Percutaneous transhepatic biliary drainage(PTBD)was associated with lower incidence of cholangitis(OR=0.32,95%CI:0.18?0.58,P<0.05),pancreatitis(OR=0.18,95%CI:0.05?0.60,P<0.05)and conversion rate(OR=0.13,95%CI:0.05?0.33,P<0.05)compared with endoscopic biliary drainage(EBD).The incidence of hemorrhage of digestive tract or hemobilia in PTBD group is higher than that in EBD group(OR=2.93,95%CI:1.33?6.45,P<0.05)and therapeutic successful rate of PTBD is higher than EBD(OR=3.72,95%CI:1.99?6.93,P<0.05).The incidence of cholangitis is divided into two subgroups according to patients'nationality for subgroup analysis and the result indicates that the incidence of cholangitis in the foreign EBD group is higher than that in the PTBD group(OR=0.21,95%CI:0.08?0.52,P<0.05),whereas there is no difference between the two groups in domestic subgroup(OR=0.48,95%CI:0.22?1.07,P=0.07).Drainage methods are divided into four subgroups by Bismuth classification.In the Bismuth IV type subgroup,the therapeutic successful rate in PTBD group is higher than that in EBD group(OR=23.89,95%CI:2.39?239.09,P<0.05)and there is no difference among the rest three subgroups.The differences in complications after drainage,biliary peritonitis,duodenum or biliary tract perforation,stent or tube dislocation,postoperative morbidity,postoperative liver dysfunction and tumor dissemination are not significant between the two groups.CONCLUSION 1.Among the aspects of complications after drainage,biliary peritonitis,duodenum or biliary tract perforation,stent or tube dislocation,postoperative morbidity,postoperative liver dysfunction and tumor dissemination for patients with resectable hilar cholangiocarcinoma,the incidence is similar between PTBD and EBD2.In term of the therapeutic successful rate,PTBD gains more satisfaction than EBD,especially among patients with Bismuth IV type HCC.3.The incidence of cholangitis and pancreatitis is higher in EBD than in PTBD.It is suggested that the method that is going to be performed should be considered carefully.4.Given the convenience,higher success rate and less complications of PTBD,patients with hilar cholangiocarcinoma who are able to undergo surgical resection can choose PTBD as a preoperative biliary drainage method.5.Which method is the optimal choice for this kind of patients to achieve preoperative biliary drainage still need high-quality and large-scale randomized controlled trials to verify.