Surgery for hilar cholangiocarcinoma or Klatskin tumours is technically very challenging. The position of the tumour is such that it is almost always involving critical structures as they enter or leave the liver in such a way that reconstruction is potentially very difficult. A number of factors limit and determine what can be done in terms of resection of hilar cholangiocarcinoma. In simple terms what is required is two contiguous segments of liver with an artery, portal vein branch and venous drainage plus a bile duct for bilioenteric reconstruction. Often this means that we must try to preserve the left lateral section or segments 2 and 3. The advantages of doing this are that the left bile duct is long, the left hepatic artery usually comes off as a branch distant from and proximal to the biliary hilus and the left portal vein is long which allows the opportunity for resection and reconstruction if required.
Segment 1 also known as the caudate lobe is invariably involved in hilar cholangiocarcinoma and it should be resected in the great majority of cases to give the best possible chance of achieving R0 resection margins.
I am going to run through a case to illustrate some of the preparatory work which may be necessary to get a patient to the point of surgery. This patient presented with painless obstructive jaundice and was found to have dilated intrahepatic ducts and a collapsed extrahepatic biliary tree on ultrasound scanning. She had no gallstones. The hospital which admitted her realised immediately that there was a potential that she had a hilar cholangiocarcinoma and performed an MRCP. This showed stricturing of the right hepatic ducts at the hilus of the liver extending to the common hepatic duct.
Importantly the referring hospital recognised this as a hilar cholangiocarcinoma and did not undertake any invasive cholangiography and referred the case to a specialist centre -the Royal Infirmary of Edinburgh.
There is a temptation in such cases to perform ERCP. This can seriously prejudice the possibility of undertaking potentially curative surgery for the following reasons.
1. Endoscopically placed stents are difficult to direct and frequently end up on the wrong side of the liver e.g the right lobe when the patient is likely to need a right or extended right hepatectomy.
2. Cholangiography can introduce sepsis into obstructed ductal systems causing cholangitis and the need to drain ductal sectors unnecessarily.
3. Stenting from below stops accurate imaging from above to define the level of ductal obstruction and to plan resection.
4. Stenting from below will traverse the tumour which may be disadvantageous from an oncological perspective.
Advice to referring clinicians in cases of suspected hilar cholangiocarcinoma is to undertake cross sectional imaging with CT and MRCP and or MRI and to discuss the case early with a specialist centre.
Looking at the cross sectional imaging for this patient the tumour can be seen involving predominantly the right ductal system but also obstructing the origin of the left duct and extending toward the caudate lobe. This tumour would therefore be classified as a Bismuth type 3A tumour.
This patient was considered to need an extended right hepatectomy and caudate lobe excision.
The first intervention which we undertook was to place a percutaneous drain in the segment 3 bile duct. This confirmed the MRCP findings that the segment 3 and 2 ducts communicated and demonstrated the level of obstruction of the left duct, it also provided biliary drainage of the left lateral section which would be the future liver remnant.
The drain can be seen in the segment 3 duct and the tip lies above the stricture. There is still some communication between the left and right duct systems as can be seen by the presence of contrast in the right duct system following PTC cholangiography. Following insertion of the biliary drain the patient’s bilirubin began to fall rapidly.
The patient then underwent hepatic volumetry of the future liver remnant
The volume measurements of the future liver remnant were
•PrePVE Total liver vol 2187ml
Seg II/III 327 ml Ratio 15%
This volume is too small for safe resection and would incur a very significant risk of post operative liver dysfunction and failure. A useful working rule for safety for the future liver remnant volume is 25% of the total functional liver volume (Schindl et al). A larger future liver remnant volume may need to considered in patients with chemotherapy associated sinusoidal obstruction syndrome, steatosis of any cause or in the presence of hepatic fibrosis.
This patient will therefore need manipulations to increase the future liver remnant and the next part of this blog will deal with portal vein embolization. Coming soon……