MyRadAgent
Home › Tools › LI-RADS v2018 calculator

LI-RADS v2018 calculator

Enter the major features for an observation in an at-risk patient. Tumour in vein and the targetoid LR-M appearances are checked first, because they take precedence over the diagnostic table however the other features read.

Exclusions — checked before the table
Nonrim arterial phase hyperenhancement

The gate feature. Rim APHE is a targetoid appearance and points to LR-M instead.

Observation size (mm)
Additional major features
Population. LI-RADS applies ONLY to patients at high risk for HCC: cirrhosis, chronic hepatitis B, or current/prior HCC. It does NOT apply to patients under 18, to cirrhosis from congenital hepatic fibrosis or a vascular disorder, or to anyone without a risk factor. Applying it outside that population attaches an HCC probability to an observation whose prior probability is entirely different.

Categories, risk and management

CategoryMeaningHCC prevalence Management
LR-1Definitely benign0%No further LI-RADS workup. Return to routine surveillance.
LR-2Probably benign~13%Continue surveillance, typically at the usual interval.
LR-3Intermediate probability of malignancy~38%Repeat or alternative imaging in 3-6 months; multidisciplinary discussion where available.
LR-4Probably HCC~74%Multidisciplinary discussion. Repeat or alternative imaging, and biopsy or treatment may be appropriate.
LR-5Definitely HCC~94%Treat as HCC. Biopsy is not required for the diagnosis.
LR-MProbably or definitely malignant, not HCC specific~36% HCCMultidisciplinary discussion; biopsy is usually required because intrahepatic cholangiocarcinoma and metastasis are in the differential and are managed differently.
LR-TIVTumour in veinhighMalignancy with venous invasion. Multidisciplinary discussion; staging changes materially.
LR-NCNot categorisablen/aImage degradation or omission prevents assessment of one or more major features. Repeat or alternative imaging.

The v2018 diagnostic table

Applies once LR-NC, LR-TIV, LR-M, LR-1 and LR-2 are excluded. "Additional" means nonperipheral washout, enhancing capsule and threshold growth — counted, to a maximum of two.

Nonrim APHESize0 additional 1 additional≥2 additional
Absent<20 mmLR-3LR-3LR-4
≥20 mmLR-3LR-4LR-4
Present<20 mmLR-3LR-4LR-5
≥20 mmLR-4LR-5LR-5

Why the exclusions come first

An observation with tumour in vein is LR-TIV however its major features read, and a targetoid observation is LR-M. Both exit the table rather than scoring through it, because both change management in a direction the table cannot express — LR-M usually needs a biopsy precisely because intrahepatic cholangiocarcinoma and metastasis are live alternatives, and LR-5's whole point is that biopsy is not required.

Related

Source. CT/MRI LI-RADS v2018 Core, American College of Radiology. View the ACR document
This is a reference implementation of a published guideline, for use by qualified clinicians. It does not account for patient-specific factors and is not a substitute for clinical judgment or a formal radiology consultation. See our full disclaimer.