Skip to main content

Health condition

Liver lesions and cysts, and how to tell benign from something that needs attention.

Most liver lesions are found by accident on a scan for something else - and most turn out to be harmless. This guide walks through how a lesion is characterised, what the benign and malignant possibilities are, and when specialist review matters.

Jump to assessment and management
A radiographer guides a patient onto the bed of an advanced 3 Tesla MRI scanner in a London imaging suite

Why trust this guide

  • 01

    Editorial team

    Written by our editorial team from the UK sources listed on each page.

  • 02

    Sourced from guidance

    Checked against NICE, British Society of Gastroenterology and Royal College of Radiologists standards you can see at the end.

  • 03

    Current for 2026

    Reflects modern UK practice for characterising incidental liver lesions found on scans.

Key facts

Liver lesions at a glance.

The essentials, in plain English - what counts as a liver lesion, the main types, and how a diagnosis gets made in the UK today.

  • What it is

    An umbrella term for any mass seen on liver imaging - most are found incidentally on a scan done for something else, and most are harmless.

  • Benign lesions

    Simple cysts, haemangiomas, focal nodular hyperplasia (FNH) and hepatic adenomas make up the large majority of what is found.

  • Malignant lesions

    Metastases are the most common malignant liver lesion overall, ahead of primary liver cancers such as HCC and cholangiocarcinoma.

  • How it is worked up

    Multiphase contrast CT or MRI usually characterises a lesion by its enhancement pattern - often without a biopsy.

  • Tumour markers

    AFP, CA19-9 and CEA help narrow the diagnosis and are checked whenever a lesion looks anything other than classically benign.

  • Who decides next steps

    A specialist hepatobiliary MDT with a dedicated liver radiologist - not a single scan report in isolation.

Why this guide matters

A calm, systematic answer to "what did they find on my scan?"

Being told a scan has "found something" on the liver is unsettling. The three points below are what actually decides whether that finding matters.

  • Most lesions are benign

    Simple cysts and haemangiomas are common, well understood, and usually need nothing more than the scan that found them.

  • The pattern on imaging does the work

    Multiphase contrast CT or MRI can characterise most lesions on its own - biopsy is the exception, not the rule.

  • A specialist MDT reviews anything unclear

    Indeterminate or higher-risk lesions go to a hepatobiliary multidisciplinary team, not a single report read in isolation.

How the diagnosis is made

From an incidental finding to a confident answer.

The steps a UK hepatobiliary team will normally follow, in order - so you know what to expect and why each step exists.

  1. 01

    Finding

    The incidental finding

    Most liver lesions turn up on a CT, MRI or ultrasound requested for an unrelated reason - abdominal pain, a health check, or staging for another condition.

  2. 02

    Finding

    Clinical and risk-factor review

    Cirrhosis, viral hepatitis, alcohol history, the combined pill, and any personal or family cancer history all change how a lesion is interpreted.

  3. 03

    Finding

    Multiphase contrast CT or MRI

    Arterial, portal-venous and delayed-phase imaging captures the enhancement pattern that distinguishes a cyst, a haemangioma, FNH, an adenoma - or something that needs closer attention.

  4. 04

    Characterising

    Tumour marker panel

    AFP (hepatocellular carcinoma), CA19-9 (cholangiocarcinoma) and CEA (bowel-origin metastases) are checked when the imaging pattern is not classically benign.

  5. 05

    Characterising

    Biopsy if indeterminate

    Reserved for lesions that imaging and markers cannot confidently classify - image-guided, and usually avoided in lesions that already look like a straightforward haemangioma or adenoma.

  6. 06

    Deciding

    MDT hepatobiliary radiology review

    A specialist multidisciplinary team - hepatobiliary surgeon, liver radiologist, oncologist and pathologist - reviews indeterminate or higher-risk lesions together.

  7. 07

    Deciding

    Agreeing a plan

    Reassurance, surveillance, or resection - the plan follows directly from what the lesion turned out to be, not from the fact a lesion was found.

Typical timeline: imaging and markers within one to two weeks, MDT review shortly after.

Benign vs malignant

The main possibilities, explained.

Four benign categories, three malignant ones - and the features that separate them. For the two most common findings, we have dedicated in-depth guides linked below.

  • Simple liver cyst

    Fluid-filled, thin-walled and extremely common - almost always an incidental finding needing no treatment. See our dedicated guide to liver cysts.

  • Haemangioma

    A benign tangle of blood vessels and the most common solid liver lesion - classic imaging appearance means no follow-up is usually needed. See our dedicated guide to liver haemangioma.

  • Focal nodular hyperplasia

    A benign overgrowth of normal liver tissue around a central scar - typically found in women of childbearing age and rarely causes symptoms.

  • Hepatic adenoma

    Linked to the combined oral contraceptive pill - benign but carries a real risk of bleeding and, in some, malignant transformation.

  • Hepatocellular carcinoma (HCC)

    The most common primary liver cancer, almost always arising in a cirrhotic or chronically diseased liver - AFP and multiphase imaging drive the diagnosis.

  • Cholangiocarcinoma

    A cancer of the bile ducts, sometimes centred at the liver hilum - CA19-9 and cross-sectional imaging usually raise the suspicion first.

  • Metastases

    Cancer spread from elsewhere - usually bowel, breast, lung or pancreas - is the single most common malignant liver lesion seen overall.

  • Red flag - growth or symptoms

    Any lesion that grows on repeat imaging, causes pain, or comes with deranged liver blood tests deserves an urgent specialist opinion.

Deep dive

Liver cysts - the full guide

Types of cyst, when they cause symptoms, and how simple versus complex cysts are managed.

Deep dive

Liver haemangioma - the full guide

Why haemangiomas are the most common solid liver lesion, and when giant haemangiomas need treatment.

Management

How liver lesions are managed in the UK.

Reassurance for classic benign findings, surveillance for borderline ones, and resection or specialist referral for symptomatic, malignant or high-risk lesions.

  • Reassurance, no follow-up

    For a classic simple cyst or haemangioma with a textbook imaging appearance - the standard outcome, and the most common one.

  • Multiphase CT or MRI characterisation

    The main diagnostic tool - a private MRI scan or CT can usually classify a lesion without any invasive step.

  • Tumour marker testing

    AFP, CA19-9 and CEA - a simple blood panel that adds weight to, or reassuringly against, a malignant diagnosis.

  • Interval surveillance imaging

    For adenomas and borderline lesions - a repeat scan at a defined interval to confirm stability before further steps are needed.

  • Stopping the combined pill

    First-line for a hepatic adenoma in a woman on oestrogen-containing contraception - lesions can shrink once the hormonal driver is removed.

  • Image-guided biopsy

    Reserved for genuinely indeterminate lesions where imaging and markers have not given a confident answer.

  • Surgical resection

    For symptomatic, malignant, or high-risk adenomas (typically over 5cm or still growing) - performed within a specialist hepatobiliary surgical unit.

  • Liver transplant assessment

    For selected HCC cases meeting transplant criteria, or extensive benign disease causing complications - assessed through a specialist liver transplant service.

What this guide is based on

The sources behind every claim on this page.

UK national guidance and specialist society standards, current at the time of last review.

Key references

Guidelines and standards we relied on.

A quiet reminder

This guide is for information, not medical advice.

Your GP or hepatobiliary specialist knows your scan, your history and your risk factors, and can tell you which parts apply to you. If in doubt, get seen.

  • NICE. Suspected cancer: recognition and referral (NG12) - hepatobiliary pathway.

  • British Society of Gastroenterology (BSG). Guidelines on the management of liver lesions.

  • Royal College of Radiologists (RCR). Standards for the imaging of focal liver lesions.

  • NHS England. Specialised hepatobiliary and liver cancer service specifications.

Red flags

When a liver lesion needs urgent attention.

Most incidental findings are reassuring. These are the situations that aren't - and where a specialist opinion is needed promptly.

  • Growth on interval imaging

    A lesion that has clearly enlarged between scans is treated as suspicious until proven otherwise, whatever it looked like the first time.

  • New symptoms

    Right upper quadrant pain, unexplained weight loss, or a palpable mass alongside a known lesion should prompt urgent reassessment.

  • Rising or abnormal tumour markers

    A climbing AFP, CA19-9 or CEA - even with a previously reassuring scan - changes the picture and needs specialist review.

  • New lesion in a cirrhotic liver

    Any new nodule in cirrhosis is treated as possible HCC until multiphase imaging and AFP say otherwise.

  • Large or growing adenoma

    Hepatic adenomas over roughly 5cm, or still growing, carry a meaningful bleeding and malignant-transformation risk and usually warrant resection.

  • Jaundice or deranged liver function

    Yellowing skin or eyes, dark urine, or abnormal liver blood tests alongside a lesion point to biliary involvement and need same-week assessment.

  • Multiple lesions

    Several lesions across the liver, especially with a known or past cancer, raise the likelihood of metastatic spread rather than a solitary benign finding.

  • Known primary cancer

    Anyone with a current or past cancer diagnosis who develops a new liver lesion should have it treated as a possible metastasis until staged.

  • Adenoma with pregnancy plans

    Hepatic adenomas can grow rapidly under the hormonal changes of pregnancy - discuss any known adenoma with a specialist before conceiving.

Living with it

A finding to understand, not to fear.

Four things that make the biggest difference once a liver lesion has been found - knowing what "reassurance" actually means, taking surveillance seriously, reviewing hormonal contraception where relevant, and knowing when to push for an MDT view.

A quiet reminder

Not every finding needs a fix - some just need naming.

A well-characterised benign lesion, once named, usually needs nothing further at all.

  1. 01 Reassurance

    A clean report often means nothing to do

    A classic simple cyst or haemangioma with a textbook appearance rarely needs another scan, let alone treatment.

  2. 02 Monitoring

    Surveillance is a plan, not a worry

    A borderline or adenoma finding on a fixed surveillance schedule is being actively managed - it has not been forgotten.

  3. 03 Hormones

    Review contraception with an adenoma

    If you are on the combined pill and have a hepatic adenoma, ask your GP or gynaecologist about alternative, non-oestrogen options.

  4. 04 Escalate

    Ask for the MDT view if anything is unclear

    If a report reads as indeterminate, ask specifically whether it has been - or will be - reviewed by a hepatobiliary MDT.

Frequently asked

Everything we get asked about liver lesions.

Quick answers on cysts, haemangioma, adenomas, biopsy and when surgery is needed.

  • What is a liver lesion?

    A general term for any abnormal area seen on liver imaging, ranging from a completely harmless simple cyst to a primary or secondary liver cancer. Most liver lesions are found incidentally and turn out to be benign.

  • Are most liver lesions cancerous?

    No. The great majority found incidentally on a scan are benign - simple cysts and haemangiomas account for most of them. Malignant lesions are the minority, and when they do occur, metastases from another cancer are more common than a primary liver cancer.

  • What is the difference between a liver cyst and a haemangioma?

    A liver cyst is a simple fluid-filled sac with a thin wall, while a haemangioma is a benign cluster of abnormal blood vessels. Both are common, both are usually picked up incidentally, and both typically need no treatment - see our separate guides to liver cysts and liver haemangioma for the full detail on each.

  • Do I need a biopsy for every liver lesion?

    No. Most lesions are confidently characterised on multiphase contrast CT or MRI alone. Biopsy is reserved for lesions that remain indeterminate after imaging and tumour marker testing, because sampling carries a small bleeding risk of its own.

  • What is a hepatic adenoma and why does it matter?

    It is a benign liver tumour strongly linked to the combined oral contraceptive pill. It matters because larger or growing adenomas can bleed suddenly, and a minority carry malignant potential - both reasons specialists often recommend stopping oestrogen-containing contraception and, for larger lesions, surgical removal.

  • When is a liver lesion treated with surgery?

    Surgery is considered for lesions that are symptomatic, confirmed or strongly suspected to be malignant, or benign adenomas above around 5cm or still growing. The decision is made by a specialist hepatobiliary multidisciplinary team, not from imaging alone.

Related content

Keep reading.