Liver questions Flashcards
What three factors are critical to deciding resectability of a liver lesion ?
1) Size of Lesion 2) Location(liver segments involved) 3) Future Liver remnant (FLR)
As a general rule, hepatic resection in a liver with normal parenchyma (no cirrhosis) requires what conditions?
1) Atleast 20% of total estimated volume post resection 2) Normal vascular inflow, outflow & biliary trainage in atleast TWO adjacent liver segments
How is FLR (Future Liver Remnant) determined?
Most common technique is CT volumetry based on 3D analysis of the liver – FLR%= %remaining liver/ Total calculated volume. – Indocyamine green retention has been used, but not widely adopted.
What FLR is recommended in patients with chronic liver disease, High dose chemotherapy or severe fibrosis?
– >40% is advised. – If resected segment/lobe is heavily infiltrated with tumor, often compensatory hypertrophy occurs to the uninvolved segments/lobe. In these cases, hepatic insufficiency is UNLIKELY.
What strategy or treatment is available to increase FLR?
–Portal Vein Embolization (PVE) may be used when FLR is the ONLY obstacle to curative resection. It is an interventional radiology procedure. – Hypertrophy occurs over several weeks (2-6 on average) in the unaffected side. –Relative contraindications: portal vein invasion by tumor & Biliary obstruction(needs to be treated first), mild portal HTN, coagulopathy, acute renal failure. – Absolute contraindication: Clinically overt portal hypertension.
In assessing resectability of the liver tumor, what principles should be considered?
– Location of tumor in discrete area w/o evolution over time are most resectable. – Bilateral or diffuse tumors are less likely to be resectable. – neoadjuvant and adjuvant treatments should be considered (TACE, ethanol injection, Y-90, RFA)
Describe Couinaud segments and relation to hepatic veins.
(Image)
Describe pringle maneuver?
Compression of portal structures (hepatic artery, portal vein and CBD) within the hepatoduodenal ligament.
A pringle maneuver is used for control of bleeding and for what other objective during liver resection?
Ischemic preconditioning
During a liver resection, there is significant bleeding from an area in segment seven. A pringle maneuver is unsuccessful in stopping hemorrhage. What is the likely source of bleeding?
Right hepatic vein. Pringle will not stop hepatic vein bleeding.
List the five types of formal hepatic resection & segments involved.
1) Right Hepatectomy (V-VIII) 2) Extended Right Hepatectomy (I, IV–VIII) 3) Left Hepatectomy (II-IV) 4) Extended Left hepatectomy (I, II-IV, V, VIII) 5) Left lateral segmentectomy (II,III)
What are the general indications for Radiofrequency ablation & ablative techniques?
– Not a candidate for resection (Usually chronic liver disease) – Poor operative candidate – Can be used in conjunction with resection to preserve liver parenchyma (i.e. Left lateral segmentectomy + RFA of a lesion in segment VII) – Lesions less than 3cm at greatest extent have best chance of success in complete destruction of tumor. – Can be done laparoscopic or by percutaneous interventional techniques –Contraindications: <6months expected survival, severe cirrhosis, portal vein thrombosis, location near large portal vascular structures or bile ducts.
What is the role of ethanol injection (EI)?
In patients with small tumors (<2cm) who are not candidates for operative resection. There can be significant absorption and intoxication from direct injection. Similar role to RFA.
What is the role of Y-90 and transarterial chemo-embolization?
In patients with HCC who are not candidates for operative resection and the tumor(s) are inappropriate for ablative techniques. – TACE involves direct injection of chemotherapeutic agents into the vascular supply of the tumor. Done as IR procedure. Can be repeated and is also thought to downstage or “manage” tumors as a bridge to transplant. –Y90 is administered in simialr fashion to TACE, but involves radioactive material to destroy tumors. Usually, limited to one application and best for large otherwise unresectable masses in patients with chronic liver disease.
When is transplantation the best option?
Pt’s with cirrhosis who meet Milan criteria for tumor size and characteristics. These patients have the lowest incidence of tumor recurrence post transplant. There are several modified protocols at several institutions that include more liberal standards, but these remain controversial and currently unproven.
