Radiation Oncology/Liver/Overview

Liver anatomy

The liver is divided anatomically into the left and right lobes, but surgically is divided into the left and right liver which does not correlate with the anatomic lobes. The left and right liver contain four segments each.

• The left part of the liver contains segments I to IV:
  • caudate lobe (I)
  • lateral segment (II and III)
  • medial segment (IV). Division between lateral and medial segment is a line between the gallbladder and IVC, which is the same as dividing at the falciform ligament.
• The right part of the liver consists of segments V to VIII:
  • anterior segment (V and VIII)
  • posterior segment (VI and VII). The division between the anterior and posterior segments is the right hepatic vein. The division between the anterior segment from the left part of the liver is the middle hepatic vein.

Child-Pugh Scoring

The score employs five clinical measures of liver disease. Each measure is scored 1-3, with 3 indicating most severe derangement.

Measure	1 point	2 points	3 points
Bilirubin (total)	<2	2-3	>3
Serum albumin	>3.5	2.8-3.5	<2.8
INR	<1.7	1.71-2.20	> 2.20
Ascites	None	Suppressed with medication	Refractory
Hepatic encephalopathy	None	Grade I-II (or suppressed with medication)	Grade III-IV (or refractory)

Chronic liver disease is classified into Child-Pugh class A to C, employing the added score from above.

Points	Class	1-year OS	2-year OS
5-6	A	100%	85%
7-9	B	81%	57%
10-15	C	45%	35%

Liver RT Tolerance

Whole liver radiation tolerance is ~30 Gy, which is not sufficient for "cure" but is sufficient for palliation of painful disease. Partial liver tolerance depends on the volume irradiated. Partial liver dose escalation to 70+ Gy has been reported, and there does appear to be some dose-response relationship. Similarly, efforts are underway to explore the role of stereotactic radiosurgery, with single doses as high as 26 Gy reported.

Please See: the Liver section under the Normal tissue tolerance page

Reviews

• PMID 16250051, 2005 — "Management of hepatocellular carcinoma." Bruix J et al. Hepatology. 2005 Nov;42(5):1208-36.