Suspected hepatocellular carcinoma in cirrhosis

LI-RADS v2018 CT/MRI; CEUS LI-RADS; AASLD HCC guidance

The indication where imaging alone makes the cancer diagnosis, and therefore the indication where the protocol is not negotiable. Arterial hyperenhancement followed by washout is the diagnosis, so a scan without those phases cannot make it, unmake it, or be salvaged by reporting.

A nodule detected on surveillance ultrasound, or a rising alpha-fetoprotein, in a patient with cirrhosis or chronic hepatitis B.

Referenced decision support — confirm against your local protocol.

Decision support, not a directive. Protocols and timings shown are typical published ones — your local protocol takes precedence, and the vetting radiologist decides.

The request in front of you

Everything is optional. Leave a field alone and the answer assumes nothing — the verdict updates as you go.

Study requested

What the referrer actually asked for. It is evidence of intent, not a constraint on the right answer.

Contrast as written

What the request form says, not what it should say.

Age

Pick a band, or type an exact age if it matters.

years

Pregnancy status

Renal risk factors

The question a vetter can actually answer from the request. An explicit “none known” is a real answer, and it removes checks rather than deferring them.

Previous contrast reaction

The pathway — tap anything already done

Marking a study complete moves the answer on. A patient arrives partway through a pathway far more often than at the start of one.

Accept as requested

CT Liver — Four Phase (LI-RADS Compliant)

CT Liver — Multiphase

What we'd amend, and why

The physiology is the whole protocol. As a regenerative nodule progresses to carcinoma its portal venous supply is lost and a new arterial supply recruited, so in the late arterial phase the tumour enhances while the surrounding liver, which is still mostly portally supplied, has not — that difference is arterial phase hyperenhancement. Later, the lesion loses contrast faster than the fibrotic parenchyma retains it, producing washout, and the fibrous capsule retains contrast on the delayed acquisition. The unenhanced series exists so that intrinsically bright fat or haemorrhage is not mistaken for enhancement. Drop any one of those acquisitions and the diagnostic criteria cannot be applied.

Nothing needs resolving before this goes ahead. Routine checks below are owned downstream.

How was this decided?

pathwayadult — Adults at risk of HCC
rulerule-contrast-reaction-premed — Prior contrast reaction and elective premedication; checked by Nurse before the scan
rulerule-metformin — Metformin and iodinated contrast; checked by Radiographer at the scanner
rulerule-paeds-dose — Child-sized technique and contrast dose; checked by Radiographer at the scanner
rulerule-pregnancy-ionising — Pregnancy status before an ionising exposure; checked by Radiographer at the scanner
rulerule-renal-iodinated — Kidney function and intravenous iodinated contrast; checked by Radiographer at the scanner
rulerule-iv-access — Intravenous access adequate for the planned injection; checked by Radiographer at the scanner

Decision support only. Local protocol takes precedence.

Handled at the scanner(4)nothing for you to do

Settled and owned downstream. Each returns to a radiologist only on the stated trigger.

Metformin and iodinated contrast
Confirm whether the patient takes metformin or a metformin-containing combination, and if so whether ACR Category II applies (eGFR below 30, known or suspected AKI, or an arterial catheter study likely to cause renal embolisation). If Category I — that is, no AKI and eGFR at or above 30 — no action of any kind is needed.
Radiographer at the scannerAt the scanner
Flags back if: The patient takes metformin AND meets ACR Category II — eGFR below 30 mL/min/1.73 m2, known or suspected acute kidney injury, or an arterial catheter procedure with likely renal arterial embolisation. Metformin plus a normal or mildly reduced eGFR is explicitly NOT a flag-back: there is no need to stop metformin before or after intravenous iodinated contrast in Category I patients, and no need to re-check creatinine afterwards.
Child-sized technique and contrast dose
Confirm that a size- or weight-based protocol is selected — child-sized kV and mAs against size-based diagnostic reference ranges — and that contrast volume is calculated by weight rather than taken from an adult default. Weight-based iodinated contrast volumes of roughly 1.5–2.0 mL/kg are widely used in paediatric CT.
Radiographer at the scannerAt the scanner
Flags back if: No paediatric or size-based protocol exists on the scanner for the requested examination, or the requested coverage or number of phases exceeds what the clinical question needs — for example a multiphase study where a single phase answers it, or whole-body coverage for a focal question.
Pregnancy status before an ionising exposure
Make the pregnancy enquiry immediately before the exposure and record the answer. In the UK this is a statutory operator duty discharged at the time of exposure under the employer’s written procedures required by IR(ME)R 2017 — it is not something the vetting radiologist can perform or pre-empt, and a request is complete without it.
Radiographer at the scannerAt the scanner
Flags back if: The patient states that she is, or may be, pregnant AND the uterus is in or near the primary beam. The exposure is then paused for re-justification by the IR(ME)R practitioner before it proceeds.
Intravenous access adequate for the planned injection
Site and test a cannula that supports the protocol flow rate, preferring an antecubital or large forearm vein, and observe the injection for extravasation. A 20-gauge or larger cannula is preferred for flow rates of 3 mL/s or more.
Radiographer at the scannerAt the scanner
Flags back if: No cannula can be sited that supports the protocol flow rate — for example only a 22-gauge hand or foot cannula for a CT angiogram needing 4–5 mL/s; or the only available access is a central line or port that is not labelled power-injectable; or an extravasation occurs.

Pathways

Big forks are separate pathways; the first whose conditions match is the one used.

Adults at risk of HCC

Matches your inputsDefault

Role	Study & protocol	Why this answers the question
First line	CT Liver — Multiphase CT Liver — Four Phase (LI-RADS Compliant) usually appropriate	The physiology is the whole protocol. As a regenerative nodule progresses to carcinoma its portal venous supply is lost and a new arterial supply recruited, so in the late arterial phase the tumour enhances while the surrounding liver, which is still mostly portally supplied, has not — that difference is arterial phase hyperenhancement. Later, the lesion loses contrast faster than the fibrotic parenchyma retains it, producing washout, and the fibrous capsule retains contrast on the delayed acquisition. The unenhanced series exists so that intrinsically bright fat or haemorrhage is not mistaken for enhancement. Drop any one of those acquisitions and the diagnostic criteria cannot be applied.
Reasonable alternative	MRI Liver MRI Liver — multiphase with extracellular gadolinium	MRI applies the same dynamic criteria with an extracellular gadolinium agent, and adds T2 signal, diffusion restriction and chemical-shift information as ancillary features. For small nodules and for a background of heterogeneous cirrhotic parenchyma it is generally the more sensitive study, and it is the natural pivot when iodinated contrast is a problem.
Problem solving	MRI Liver MRI Liver — hepatobiliary contrast agent	A hepatobiliary agent adds a functional discriminator: hepatocyte uptake at twenty minutes distinguishes a lesion containing functioning hepatocytes from one that does not, which helps with an early lesion that has not yet developed classic arterial hyperenhancement. The trade-off is a weaker arterial phase from the smaller bolus and altered washout appearances, so it is a problem-solving choice rather than the default.
Problem solving	Ultrasound abdomen Contrast-enhanced ultrasound (CEUS) — focal liver lesion characterisation	Contrast-enhanced ultrasound applies the same physiological argument with a different agent and has its own reporting algorithm for at-risk patients. Microbubbles are a pure blood-pool tracer cleared by exhalation, not filtered by the kidney, so there is no nephrotoxicity, no eGFR to obtain and no reason to defer — which makes this the study that keeps the diagnostic pathway open for a cirrhotic patient with hepatorenal impairment or on dialysis, in place of an unenhanced CT that cannot be reported to any algorithm. Enhancement is watched continuously rather than sampled at discrete acquisitions, so arterial hyperenhancement is seen happening and the timing and degree of late wash-out are observed. Its limits are specific and must not be glossed: one bolus interrogates one lesion in one acoustic window, so it characterises rather than surveys and it cannot stage; a deep lesion in a large, steatotic or nodular liver may be unreachable; and the wash-out thresholds are not the CT or MRI ones, because the agent stays intravascular — reading them across generates false calls in both directions.

Pitfalls

Accepting a single portal-venous CT abdomen for a surveillance nodule. It is the phase in which a hypervascular tumour is least conspicuous, because by then the parenchyma has caught up.
Allowing an early rather than late arterial acquisition. If the hepatic veins are not yet opacified and the portal vein is unenhanced, the tumour has not had time to enhance and the study will be falsely negative.
Applying the diagnostic criteria to a patient who is not actually at risk, which produces false positives from haemangiomas and hypervascular pseudolesions.
Treating a hepatobiliary-agent study as interchangeable with an extracellular-agent study for washout assessment.
Reporting arterial enhancement without checking the unenhanced series for intrinsic T1 or high attenuation, which is the commonest false call.
Cancelling the diagnostic pathway because of renal function. Microbubble contrast is not renally excreted and needs no eGFR, and a macrocyclic gadolinium agent carries a vanishingly small risk below an eGFR of 30 — an unenhanced liver CT reported as showing no tumour is the one genuinely unsafe answer here, because the diagnostic criteria cannot be applied to it at all.
Reading a contrast-enhanced ultrasound as though it surveyed the liver. One bolus interrogates one lesion in one acoustic window; staging and the search for other nodules remain a CT or MRI question.

Priors — what to pull first

Retrieve every previous cross-sectional study of the liver. Threshold growth over time is itself a diagnostic criterion, and it cannot be applied without the comparison.
Note any previous ablation, chemoembolisation or resection, because treated tissue enhances abnormally and is assessed on a different scale.

What makes a good request

Being at risk is part of the diagnostic criteria. The same imaging appearances in a non-cirrhotic liver do not carry the same meaning, which is why this card and the incidental liver lesion card diverge.
State the cirrhosis aetiology and any previous locoregional therapy: treated lesions are assessed against different expectations.

Scoring this once it is done

The classification and risk tools this question ends in.

LI-RADS v2018 (CT/MRI)Child-Pugh Score (Child-Turcotte-Pugh)BCLC Staging & Treatment Strategy (2022 Update)Milan Criteria / UCSF (Expanded) Criteria MELD 3.0 Score ALBI (Albumin-Bilirubin) Grade mRECIST for Hepatocellular Carcinoma FIB-4 (Fibrosis-4) Index APRI (AST-to-Platelet Ratio Index)Hepatic Steatosis (CT & MRI)Spleen Volume & Splenic Index Liver Volume (CT/MRI/US) + Expected Volume RECIST 1.1 Tumor Response

How these studies are acquired

Contrast, phases and timing for every study on the pathways above.

CT Liver — Four Phase (LI-RADS Compliant)MRI Liver — multiphase with extracellular gadolinium MRI Liver — hepatobiliary contrast agent Contrast-enhanced ultrasound (CEUS) — focal liver lesion characterisation

Confirm locally

CT Liver — Four Phase (LI-RADS Compliant): timings are typical — confirm against local protocol.
Timings, contrast volumes and rates above are typical published values. Your department's protocol, scanner and patient population decide the actual numbers.
Safety thresholds and premedication policy follow local policy where it differs from the cited guidance.

References

Implemented from the cited published sources. Educational and workflow support only; confirm against current guidelines and local policy before clinical use.