Section: Surgical Oncology Curriculum: Curriculum, page 70

Indications and Patient Selection

Fall into four groups:
- Cirrhosis (waitlists usually based off MELD score)
- Acute Fulminant Liver Failure
- Metabolic Liver Disease
- Primary Hepatic Malignancy
Most common indication is Chronic Liver Failure
- Hep C in USA
- Hep B in Asia and endemic countries
- Primary biliary cirrhosis
- Primary sclerosing cholangitis
- NASH
Biliary Atresia most common indication in children
- Children account for ~ 10–15% of all liver transplants
Acute fulminant liver failure requiring transplantation on an urgent basis accounts for approximately 10%
- Usually viral or drug-induced (e.g. paracetamol OD)
Metabolic diseases
- Wilson’s Disease, Oxalosis and α1-Antitrypsin Deficiency
Primary hepatic malignancy is more common in cirrhosis, esp. virally induced
- May be best treated by transplantation because tumour resection may leave insufficient functional liver tissue behind
Cholangiocarcinoma has a high recurrence rate and is seldom an indication for transplantation

MELD Score

Model for End-stage Liver Disease
- Statistical model that predicts 3 month mortality in patients with cirrhosis
- Developed to predict who would benefit from TIPSS (score < 14) or those who would benefit from direct to transplant (score > 24)
- Now used to prioritise liver transplants
- If a patient has dialysed twice in the last week - the value for the serum creatinine should be 4
- NOT designed for HCC pts
HCC patients
- The MELD score will not appropriately prioritise HCC patients (will under-predict there mortality)
- Decompensation/derangement may happen late in the cancer disease progression
- Pts may not get prioritised for transplantation early enough
  - Priority points now given to HCC patients (Modified MELD)
In the UK they have modified the MELD to include sodium in the formula - called the MELD-NA
- Is likely more accurate

Transverse abdominal incision with a midline extension
- Diseased liver is mobilised
- Because of portal hypertension, the recipient hepatectomy is often the most difficult part, esp. if previous surgery
- CBD divided as close to liver as possible
- Mobilisation
  - Dissect the intrahepatic vena and control it with a nylon tape.
  - Divide the peritoneal attachments of the liver, starting with the left triangular ligament and proceeding to the falciform ligament, thus exposing the anterior surface of the supra-hepatic vena cava.
  - Completely mobilising the retrohepatic vena cava from the posterior abdominal wall, ligating and dividing the right adrenal vein.
- Ligate the portal vein and hepatic artery - maximising the length of the vessels for subsequent re-implantation of the new graft.
Occlusion of the vena cava and portal vein results in a reduction in cardiac output and may necessitate the use of veno-venous bypass

After placing the donor liver in position
- Supra- and infrahepatic caval anastomoses are performed
- The portal vein and the hepatic arterial anastomoses are then completed and the graft is reperfused
- Finally, biliary drainage is re-established
  - Duct-to-duct anastomosis, end-to-end (without a T-tube)
  - Roux-en-Y may be needed for biliary atresia or sclerosing cholangitis
Many pts undergoing liver transplantation are ill and the surgery involved can be very demanding
Optimal peri-operative management crucial for success and presents a major challenge
- Blood loss during and after the transplant procedure can be considerable
- Management of coagulopathy is particularly important
- Measured repeatedly and corrected appropriately with FFP, cryoprecipitate and platelets

Haemorrhage
- Haemostasis essential
- Liver may need packing and re-exploration
- Evacuation of haematoma required to avoid infection
Hepatic Artery Thrombosis
- May occur spontaneously or as a result of acute rejection
- More common in children
- Presents – unexplained transaminase rise, fever, bile leak
- Doppler USS or angiography to diagnose
- Urgent re-transplantation usually required
Portal Vein Thrombosis
- More insidious
- Doesn’t’t usually require re-transplantation
Biliary
- Leaks uncommon
- Stenosis more common
- Usually occurs late
- Managed by endoscopic dilatation and stenting

Until recently, major factor limiting paediatric liver transplantation was the lack of donor livers of suitable size
Development of techniques for using adult livers reduced in size by cut-down techniques has helped - Split liver techniques
For small children the lateral segment of the left lobe is often used
But the entire left lobe or the right lobe may also be used

Depends on underlying disease
Best results are seen in patients with chronic liver disease
Transplantation for acute liver failure
- Higher mortality rate in the early post-transplant period
- Because of multi-organ failure,
- But those who recover have very good long-term liver allograft survival
Transplanted for tumour
- Very good early outcome
- Ultimately fare less well because of recurrence
Liver transplantation following Hep B or C may develop graft failure as a result of recurrent viral disease
- But the availability of improved anti-viral therapy has helped reduce this problem

Rationale
- Removed both detectable and undetectable tumour nodules from both lobes
- Simultaneously treats underlying cirrhosis
- Prevents underlying complications associated with Portal HTN and Liver failure
Patient Selection
- Based on the fact that patients should have same survival post-op as patients for that have transplants for other reasons
- Low risk of tumour recurrence (low tumour burden)
Milan Criteria
- A single tumor that is no larger than 5 cm in diameter
- Up to three tumors, each no larger than 3 cm in diameter
- No evidence of vascular invasion or extrahepatic disease
University of California San Francisco Criteria (UCSF)
- Single tumour < 6.5cm or 2-3 tumours < 4.5cm
- With total tumour diameter < 8cm
- No vascular invasion
- No extra-hepatic spread

Waitlist often long (can be > 12 months)
- Up to 25% may be subsequently excluded from transplant while waiting due to disease progression
Potential ways to manage this
- Live-donor liver transplant
- No waitlist, faster
- But risk to donor, small grafts, difficulty with finding donor
Amendments to liver allocation policies
- Priority MELD points given to those with HCC
Treatment of tumour while waiting
- Resection, TACE, Ablation
- May avoid progression so stays within transplant criteria