Keywords
late-onset hemobilia - arteriobiliary fistula - arterial injury - radionecrosis
Introduction
Although rare, a variety of conditions, including percutaneous biliary procedures
and liver tumors, may lead to hemobilia.[1]
[2] Late presentation is merely described in a couple of manuscripts in the literature.[3] We present an acute arteriobiliary fistula that emerged 6 months after biliary drainage
and subsequent transarterial radioembolization (TARE) in a patient with cholangiocarcinoma.
Case Report
A 55-year-old male who presented with obstructive jaundice caused by a magnetic resonance
imaging (MRI)-proven 4-cm liver mass in segment six was referred for biliary drainage.
The tumor had invaded the right portal vein and the main bile duct while abutting
the right hepatic artery as revealed in the MRI. An external-internal biliary drainage
catheter was placed, and biopsy was proven to be a cholangiocarcinoma. Our institutional
multidisciplinary tumor board recommended TARE and concomitant systemic chemotherapy.
The initial planning arteriography demonstrated tumor vascularity supplied from the
right hepatic artery. Right lobar TARE with 7 GBq of yttrium-90 glass microspheres
was performed to deliver an estimated dose of 110 Gy to the treatment volume and 190
Gy to the tumor volume. After four cycles of systemic chemotherapy including gemcitabine
and cisplatin, surveillance MRI was performed 3 months posttreatment which showed
necrosis and size reduction of the tumor from the maximal width of 38 to 26 mm indicating
partial response according to RECIST 1.1.
Clinical findings and pathological investigations had been unremarkable during follow-up
except for somewhat fluctuating liver functions. Six months after TARE, the patient
was brought to the emergency department with hematemesis and collapse. Heart rate
was slightly high at 116 beats per minute, blood pressure was around 90/55 mm Hg,
and hemoglobin level was 8.2 g/dL. Patient had deteriorated when upper gastrointestinal
endoscopy was scheduled. An emergency computed tomography depicted widespread necrosis
of the right lobe and extravasation of intravascular contrast agent into common bile
duct ([Fig. 1A, B]). This finding was confirmed by a catheter angiography, which showed a right hepatic
artery fistula to common bile duct. The segmental branches of the right hepatic artery
distal to the fistula were not filling on angiography. The proximal right hepatic
artery displayed diffuse wall irregularity starting from its origin up to the fistula
site which was new when compared with the angiography performed before TARE. The fistula
was catheterized with a 2.7F microcatheter (Progreat; Terumo, Tokyo, Japan) placed
coaxially through a 5F Simmons-1 catheter (Radiofocus Glidecath; Terumo). The entire
segment of the proximal right hepatic artery was embolized with two 0.018-inch pushable
hydro-coils (Azur; Terumo) ([Fig. 2A, B]). The patient was stable after the procedure and did not need any further transfusions.
Fig. 1 Computed tomography (CT) angiography shows extravasation of contrast agent into the
common bile duct (white arrow) which is seen coursing along the drainage catheter
(A). Widespread necrosis of the right lobe (white asterisk) is noted on portal phase
contrast-enhanced CT (B).
Fig. 2 Proximal right hepatic artery (arrows) demonstrates wall irregularity starting from
its origin up to the fistula site (A). Postembolization angiogram showing coil embolized proximal right hepatic artery
with pushable hydro-coils (B).
Discussion
A fistula between the biliary tree and the accompanying vascular structures—either
the hepatic arterial or portal venous system—is a rare cause of upper gastrointestinal
bleeding. Percutaneous biliary intervention is the most common cause of this condition,
while other causes such as inflammation and liver tumors are infrequent.[1] To the best of our knowledge, there is only one reported case of arteriobiliary
fistula related to chemoradiotherapy of intrahepatic cholangiocarcinoma.[2] Hemobilia might rarely be observed months or even years after the procedure.[3] Since an arterial injury is the most common cause in such cases, it requires immediate
management due to severity of the clinical presentation.[3]
TARE is utilized increasingly in intrahepatic cholangiocarcinomas as the efficacy
of systemic chemotherapy is limited. While biliary obstruction does not pose an absolute
contraindication, radioembolization is not proposed in hilar cholangiocarcinomas.
Biliary complications including radiation cholecystitis, radiation-induced cholangitis,
abscess, bilomas, strictures, and necrosis have been reported up to 10% after TARE.
Microvascular injury and vasculitis of biliary plexus were the proposed biliary injury
mechanism in these cases.[4] Widespread necrosis is accepted to be the principal culprit in major arterial injuries
seen after radiotherapy of head and neck tumors. At the same time, radiation has also
been implicated to weaken the arterial wall by obliterating the vasa vasorum.[5]
In our case, an external-internal drainage catheter had been placed through the intrahepatic
cholangiocarcinoma before TARE. During the 6-month follow-up, continuous erosion due
to drainage catheter and developing radiation necrosis of tumor in the vicinity of
hepatic hilum could have led to hepatic artery injury and arteriobiliary fistula.
Unlike other direct hepatic artery injuries that usually spare vascular structures
other than the fistula site, we observed wall irregularity throughout the right hepatic
artery. Therefore, coil embolization of the entire parent artery starting from its
origin up to the biliary fistula site was performed. Hayano et al proposed that presence
of hepatic arterial wall irregularity in the segment proximal to the fistula may suggest
tumoricidal effects of radiotherapy extending beyond the tumor to involve the blood
vessels in the radiated depth as the possible cause for hepatic artery injury rather
than direct catheter-induced erosion.[2] This finding was similar to ours in which the right hepatic artery showed wall irregularity
in its entire proximal segment up to the fistula compared with a normal angiogram
6 months prior. Given the imaging findings, we think both factors—tumor necrosis and
catheter erosion—might have played a role in our case.
Conclusion
TARE of liver tumors that cause biliary obstruction could cause unpredictable large
necrosis; such radiation-induced necrosis if affecting an encased blood vessel may
contribute to late presenting arterial injuries.
