Wednesday, April 25, 2012

Liver biopsy

Liver biopsy (LB) is the gold standard for (i) liver disease staging,
(ii) treatment decisions and (iii) prognostication, as it may reveal
advanced fibrosis or cirrhosis that necessitates surveillance for
HCC and/or screening for varices.
Before treatment LB is indicated for prognostic purposes and
guiding treatment decisions. If LB shows significant fibrosis
treatment should be initiated, otherwise, treatment can be
deferred (Afdhal 2009). Individualized treatment decisions are
based on the severity of liver disease. Treatment is indicated in
patients with compensated cirrhosis provided they do not have
contraindications to therapy.
36 | Hepatitis C Treatment
Post-treatment LB is essential to demonstrate regression of
cirrhosis after viral supression. It is not recommended for
assessment of the efficacy of therapeutic regimens, unless
hepatic safety issues impose it.
Table 2.3 – Liver fibrosis evaluation methods*
Methods Categories Classification Comments
1) Invasive Liver biopsy Percutaneous
Laparoscopic
Scoring systems are presented
in Table 2.4
Indirect markers Biomarker combinations or
composite indexes
Serum
biochemistry
Direct markers Reflect extra cellular matrix
removal/deposition, the
balance between hepatic
fibrogenesis and fibrolysis, or
cytokines (TGF-β 1† and PDGF†)
associated with fibrosis
Imaging
techniques
Elastography
Ultrasonography
CT, MRI, PET
Fibroscan® is the most used
technique
2) Non-invasive
Genetic
markers
Estimate the
transdifferentiation of hepatic
stellate cells to myofibroblasts
* According to data from Ahmad 2011.
† TGF-β1: transforming growth factors β1; PDGF: platelet derived growth factor
Different scoring systems (Table 2.4) have been defined in order
to classify the extent of necroinflammatory activity (grading)
and the extent of fibrosis (staging) in LB.
However, LB is invasive and has a number of drawbacks:
– substantial sampling error (extracts only 1/50,000 of the
liver)
– variability in interpretation
– potential serious adverse outcomes (bleeding)
– high cost (approximately $1000–$1500 per biopsy)
– low patient’s acceptability/reluctance to undergo repeated
biopsies
Patients’ monitoring during and after treatment | 37
Table 2.4 – Scoring systems for histological stage*
Stage IASL
(Desmet 1994 )
Batts-Ludwig
(Batts 1995)
Metavir
(Bedossa 1996)
Ishak
(Ishak 1995)
0 No fibrosis No fibrosis No fibrosis No fibrosis
1 Mild fibrosis Fibrous portal
expansion
Periportal
fibrotic
expansion
Fibrous expansion of
some portal areas
with or without short
fibrous septa
2 Moderate
fibrosis
Rare bridges or
septae
Periportal
septae
Fibrous expansion of
most portal areas
with or without short
fibrous septa
3 Severe fibrosis Numerous
bridges or
septae
Porto-central
septae
Fibrous expansion of
most portal areas
with occasional
portal to portal
bridging
4 Cirrhosis Cirrhosis Cirrhosis Fibrous expansion of
most portal areas
with marked
bridging
5 Marked bridging with
occasional nodules
6 Cirrhosis
* According to data from

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