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Paper text:
a 63-year - old man , who had been under treatment for alcoholic cirrhosis and hepatocellular carcinoma , was admitted emergently to our hospital because of black stool .
a blood test revealed increase of the serum levels of hepatobiliary enzymes , jaundice , and anemia .
an urgent upper gastrointestinal endoscopy was performed , which did not reveal the bleeding source .
lower gastrointestinal endoscopy and capsule endoscopy were also performed ; however , the site of bleeding could not be identified .
based on the findings of abdominal ultrasonography ( us ) and abdominal enhanced computed tomography ( ct ) , hepatocellular carcinoma with invasion of the left intrahepatic bile duct and biliary duct dilatation was suspected ( fig .
endoscopic retrograde cholangiopancreatography ( ercp ) revealed a filling defect in the area extending from the beginning of the left intrahepatic bile duct to the hepatic portal region , confirming bleeding from the duodenal papilla , which led to the diagnosis of hemobilia ( fig .
hepatocellular carcinoma was detected by brushing cytology of the filling defect area ; thus , the hemobilia was determined to be caused by hepatocellular carcinoma invasion of the bile duct . because it was difficult to stop the bleeding by transcatheter arterial embolization ( tae ) , partly as a result of repeated sessions of transcatheter arterial chemoembolization ( tace ) which the patient had previously undergone
, we placed a fully covered metallic stent that extended from the common bile duct to the right intrahepatic bile duct branch , compressing the filling defect area of the common bile duct . during the 2 months until the patient died of cancer , the gastrointestinal bleeding and anemia
hemobilia represents gastrointestinal bleeding that develops as a result of communication between blood vessels and the biliary tract , which causes the blood to reach the duodenal papilla .
it is characterized by biliary colic as the initial symptom , and the complications of cholangitis , obstructive jaundice and/or anemia .
the causes of hemobilia include inflammation , calculus , tumor , injury , blood vessel disorder , and surgery . in regard to tumor causes
, hemobilia is often caused by invasion of the bile duct by hepatocellular carcinoma , a hypervascular tumor .
tace or radiofrequency ablation therapy is widely performed for the treatment of hepatocellular carcinoma at present .
recurrence or progression of cancer or repeated treatment of the cancer using the aforementioned modalities may cause invasion of the biliary tract by the hepatocellular carcinoma ; sometimes , arterial injury due to treatment may cause formation of a pseudoaneurysm .
our patient had undergone repeated sessions of tace for the hepatocellular carcinoma , which had resulted in invasion of the biliary tract by the liver cancer . in general , definitive diagnosis is made by esophagogastroduodenoscopy , which confirms bleeding from the duodenal papilla .
abdominal us and abdominal enhanced ct are performed to identify the source of the bleeding , as well as ercp for biliary drainage to control the comorbid cholangitis . in the present case ,
in general , if biliary tract drainage is required , a biliary tract drainage tube is placed after the cholangiography . however , because the tube is prone to blockage by blood clots , a cleanable external fistula tube is recommended rather than an internal fistula tube . if active hemorrhage accompanied by worsening of the anemia is suspected , abdominal angiography is performed to selectively image the hepatic artery .
then , definitive diagnosis can be made if the culprit vessel is identified and extravasation into the biliary tract is demonstrated .
then , embolization of the culprit vessel is recommended because it is less invasive and associated with a high likelihood of hemostasis [ 1 , 2 , 3 , 4 , 5 , 6 ] .
however , since this patient had undergone repeated sessions of tace , it was difficult to approach the culprit vessel and stop the bleeding . in cases where even tae fails to establish hemostasis , surgical therapy , such as hepatic artery ligation or hepatectomy ,
is required . however , since this patient had advanced hepatocellular carcinoma and cirrhosis of the liver , such highly invasive surgical therapy was not opted for . in patients with difficult hemostasis , as in this patient , there are a few reports of cases treated by placement of a covered metallic stent in the biliary tract [ 7 , 8 ] . in general , placement of a covered metallic stent in the hepatic hilar bile duct may cause cholangitis due to bile duct branch occlusion , and is not recommended . in this case , however , we placed a fully covered metallic stent in the hepatic hilar bile duct to control hemobilia secondary to bile duct invasion caused by hepatocellular carcinoma , because of the difficulty in establishing hemostasis and the advanced terminal cancer . in the end , because of the direct compression hemostasis to the tumor site ( common bile duct ) achieved with the fully covered metallic stent and secondary compression hemostasis due to blood clots ( left intrahepatic bile duct ) , the bleeding could be controlled .
although cholangitis did not occur in our case , measures such as placement of an endoscopic nasobiliary drainage tube into the stent - obstructed bile duct may need to be considered for the control of potentially complicating cholangitis .
thus , placement of a covered metallic stent would seem to be a valid option that can be used for the treatment of hemobilia in patients with advanced cancer and difficulty in the establishment of hemostasis .
hemobilia represents gastrointestinal bleeding that develops as a result of communication between blood vessels and the biliary tract , which causes the blood to reach the duodenal papilla . 
 it is characterized by biliary colic as the initial symptom , and the complications of cholangitis , obstructive jaundice and/or anemia . in general , 
 definitive diagnosis is made by esophagogastroduodenoscopy which confirms bleeding from the duodenal papilla . 
 abdominal us and abdominal enhanced ct are performed to identify the source of the bleeding , as well as ercp for biliary drainage to control the comorbid cholangitis . 
 if active hemorrhage accompanied by worsening of the anemia is suspected , abdominal angiography is performed to selectively image the hepatic artery . 
 then , embolization of the culprit vessel is recommended . in our patients with difficult hemostasis , because of the direct compression hemostasis to the tumor site achieved with the fully covered metallic stent and secondary compression hemostasis due to blood clots , the bleeding could be controlled .