St Vincent’s University Hospital is a tertiary referral centre for hepatobiliary surgery.
As such,
we encounter a large number of patients with cirrhosis and hepatocellular carcinoma.
LI-RADS applies in patients at high risk for HCC, namely those with:
- Cirrhosis OR
- Chronic hepatitis B viral infection OR
- Current or prior HCC
Including
- Adult liver transplant candidates and recipients
- Post-transplant patients
LI-RADS does not apply in patients:
- Without the above risk factors
- < 18 years old
- With cirrhosis due to congenital hepatic fibrosis
- With cirrhosis due to a vascular disorder such as hereditary hemorrhagic telangiectasia,
Budd-Chiari syndrome,
chronic portal vein occlusion,
cardiac congestion,
or diffuse nodular regenerative hyperplasia
We use the LIRADS scoring system to divide the lesion into five major categories ranging from LR-1 (definitely benign) to LR-5 (definitely HCC).
LI-RADS category 1:
For observations that are definitely benign because they have features diagnostic of a benign entity or have spontaneously disappeared at a follow-up examination.
LI-RADS category 2:
For probably benign observations because they have features suggestive but not diagnostic of a benign entity.
LI-RADS category 3:
For observations that do not meet criteria for the other categories and therefore have a moderate probability of being either HCC or a benign entity.
LI-RADS category 4:
For observations that are probably HCC but do not meet the criteria for being considered diagnostic of HCC.
LI-RADS category 5:
For masses with features diagnostic of HCC because of arterial hyperenhancement in combination with lesion size,
growth,
and venous phase imaging features.
LI-RADS 5V:
Observations associated with venous invasion.
LI-RADS 5T:
After treatment,
lesions previously considered LI-RADS 5 are categorized LI-RADS 5T.
LI-RADS category OM (other malignancy):
Is used to categorize lesions that appear to be malignant but are thought to have imaging features more suggestive of malignancies other than HCC,
such as cholangiocarcinoma and metastasis.
Ancillary features favoring malignancy:
Favoring malignancy in general,
not HCC in particular:
• US visibility as discrete nodule
• Subthreshold growth
• Restricted diffusion
• Mild-moderate T2 hyperintensity
• Corona enhancement
• Fat sparing in solid mass
• Iron sparing in solid mass
• Transitional phase hypointensity
• Hepatobiliary phase hypointensity
Favoring HCC in particular
• Nonenhancing “capsule”
• Nodule-in-nodule
• Mosaic architecture
• Blood products in mass
• Fat in mass,
more than adjacent liver
Ancillary features favoring benignity
• Size stability > 2 yrs
• Size reduction
• Parallels blood pool
• Undistorted vessels
• Iron in mass,
more than liver
• Marked T2 hyperintensity
• Hepatobiliary phase isointensity