This document has been produced with:
- The British Association for the Study of the Liver
- The British Society of Gastrointestinal and Abdominal Radiology
- The British Society of Gastroenterology
- The Society of Radiographers and The College of Radiographers
- The British Liver Nurses’ Association
- Hepatocellular Carcinoma UK
- The British Medical Ultrasound Society
- The British Liver Trust
- The Royal College of Radiologists
Purpose
This document sets out the guidance to imaging departments for delivering high quality ultrasound surveillance for patients at risk of hepatocellular carcinoma.
Please refer to the Hepatocellular carcinoma surveillance: minimum standards for further information on setting up and optimising HCC surveillance pathways.
Introduction
Liver cancer is the fastest-rising cause of cancer-related deaths in the UK. The most common form of primary liver cancer is hepatocellular carcinoma (HCC), accounting for 85% of all primary liver cancers.
Already over 6,200 people are diagnosed with HCC each year. The incidence has risen by 50% over the past decade and is expected to rise further.
Most HCCs are diagnosed in patients with cirrhosis and/or chronic hepatitis B infection, who are at a higher risk of developing HCC.
Existing evidence suggests only around 20% of HCCs are currently diagnosed at an early stage (1 or 2). Earlier detection provides greater opportunities for curative treatment, such as surgery or ablation.
HCC can be detected by non-invasive imaging tests, including ultrasound (US), computed topography (CT) and medical resonance imaging (MRI), before symptoms develop.
National Institute for Health and Care Excellence guidelines recommend 6-monthly US surveillance for patients with cirrhosis and some patients with hepatitis B infection, who are at higher risk of developing HCC.
This guidance provides direction on how imaging services should deliver HCC US surveillance in high-risk populations.
The focus of this is service delivery; this guidance does not address scanning technique or image interpretation, which were considered out of scope. It is presented as a series of statements, which are the agreed minimum standards for an HCC US surveillance service, with supporting text.
Guidance statements
Service organisation
Statement 1: 6-monthly hepatocellular carcinoma ultrasound (HCC US) surveillance should be offered to eligible patients at risk of developing HCC
The companion guidance (Hepatocellular carcinoma surveillance: minimum standards, 2024), developed by the NHS England Early Diagnosis of Liver Cancer Expert Advisory Group, sets out eligibility and exclusion criteria for US surveillance, which is aligned with other national and international guidance.
As specified in this guidance, patients entering HCC US surveillance should receive written and verbal information about the goals of surveillance. After appropriate counselling, patients should have the opportunity to opt out.
Statement 2: The appropriateness of ongoing surveillance should be reviewed after each HCC US surveillance episode
While in an HCC US surveillance programme, some patients may develop complications of their liver disease or other medical conditions which render them ineligible for curative HCC treatment.
Examples would be severe portopulmonary hypertension, end-stage heart failure, or other non-curative organ malignancies.
In this situation, ongoing HCC US surveillance becomes inappropriate. Consequently, the appropriateness of ongoing surveillance should be reviewed by the clinical team after each HCC US surveillance episode.
If cessation of HCC US surveillance is being considered, this should be discussed with the patient.
Statement 3: Imaging services should be organised to promote adherence to HCC US surveillance
The benefit of HCC US surveillance is only realised with regular attendance.
Patients who are at risk of HCC come from a wide range of social and economic backgrounds, including those from underserved communities.
To be effective, imaging services must consider strategies that maximise adherence to their HCC US surveillance programme.
Below are some examples steps that imaging services could take to promote adherence:
- Offering flexibility in both time and location of appointments, for example appointments in the evenings or at weekends, or at community diagnostic centres.
- Combining US appointments with other healthcare visits.
- Providing clear instructions on how to rearrange appointments.
- Contacting patients through alternative methods of communication, such as text messaging (postal-only communication is considered insufficient for harder-to-reach patient groups).
- Patient information should be available in multiple languages, and use of translation services should be considered in the patient pathway.
Refer to the Hepatocellular carcinoma surveillance: minimum standards for more information.
Statement 4: Gastroenterology/hepatology secondary care teams should be responsible for initiating and acting on HCC US surveillance episodes
US surveillance for HCC should be managed by hepatologists/gastroenterologists with a specialist interest in liver disease and/or delegated to liver nurse specialists.
Responsibility for referring for each US surveillance examination or alternative surveillance imaging, and acting on the results of surveillance tests, should lie with these teams; and should not be delegated to other secondary care clinicians, primary care or imaging departments.
These teams should be resourced appropriately to deliver this activity.
Statement 5: All HCC US surveillance episodes should be requested under a dedicated imaging procedure code for HCC US surveillance
The national interim clinical imaging procedure code (NICIP)/radiology information system (RIS) code is:
- [USRLV] US Surveillance liver hepatocellular Ca
- SCT-ID 990271000000107
Comprehensive ongoing service evaluation and quality improvement requires that all HCC US surveillance episodes are readily identifiable.
The national NICIP/RIS code for HCC US Surveillance [USRLV] should be used (rather than more generic codes, such as US Abdomen or US Liver).
To ensure these examinations are requested, scheduled, and performed appropriately, HCC US surveillance services should work in collaboration with their picture archiving and communications system (PACS)/RIS teams, bookings teams, ultrasound operators and referring clinicians.
Statement 6: Images obtained during HCC US surveillance examinations should be available for review on the PACS of the requesting healthcare organisation; and they should be available for review at the time of subsequent US examinations
The availability of the images obtained during HCC US examinations is critical when interpreting subsequent imaging and during clinical discussions.
Images obtained during all HCC US surveillance examinations must be available on the PACS of the requesting healthcare organisation – typically a secondary care provider(s).
Relevant prior imaging must also be accessible to practitioners performing subsequent HCC US surveillance to enable direct, real-time comparison.
This issue is a particular consideration for HCC US surveillance services, where US examinations are being outsourced to external providers.
Statement 7: Providers of HCC US surveillance should engage with healthcare commissioners and cancer alliances to ensure sufficient US delivery capacity and expertise is available to support high quality 6-monthly HCC US surveillance for their local population
Imaging services are encouraged to engage with their local cancer alliance to discuss demand and capacity to deliver US surveillance for HCC.
Cancer alliances are supporting liver services to invite >80% of patients with cirrhosis/advanced fibrosis to 6-monthly ultrasound surveillance, and support >60% of those invited to attend.
This involves working with relevant integrated care boards and/or local community diagnostic centres to ensure sufficient ultrasound capacity is available.
Details of cancer alliances can be found on the NHS England website.
Statement 8: HCC US surveillance services should have a nominated lead radiologist and sonographer responsible for supporting training, service delivery and quality assurance
Each department should have both a nominated lead radiologist and a sonographer, who work collaboratively to ensure delivery of a high-quality HCC US surveillance service.
Sufficient, protected time to carry out these responsibilities should be considered and agreed with line managers.
Statement 9: US machines used for HCC surveillance should be maintained to established quality standards and their technical set up should be optimised and standardised for HCC detection
It is expected that HCC US surveillance will be carried out on cart-based US machines of a medium to high specification, with availability of at least a low frequency curvilinear and high frequency linear probe.
The presets for some fields of US, such as bowel imaging, are based on national consensus of expert opinion. A similar approach to presets used in livers with advanced fibrosis/cirrhosis could reduce variation in surveillance standards, although the heterogeneity of the cirrhotic patient population makes a ‘one size fits all’ approach challenging.
It is therefore recommended that each machine in each centre is optimised by the HCC US surveillance lead sonographer and/or radiologist, with a preset for HCC US surveillance specified (which may be a manufacturer specified preset).
Both machines and probes will undergo annual quality assurance checks by the local medical physics department or equivalent, and frequent interim quality assurance tests performed and documented by operators.
The standard recommendation is that equipment should be reviewed every 4 to 6 years, and decisions made on the review outcome as to whether to replace.
Performance of hepatocellular carcinoma ultrasound surveillance
Statement 10: hepatocellular carcinoma ultrasound (HCC US) surveillance should be performed by an appropriately trained and experienced sonographer or consultant radiologist
All imaging procedures, including HCC US surveillance scans, generate false positive and false negative findings and it is desirable to minimise these. Adequacy of liver visualisation also has a measurable impact on the diagnostic performance of US surveillance for HCC.
US surveillance must be undertaken by trained, competent and experienced US practitioners and/or sonographers.
Pathways for developing competency in abdominal US, including liver US, are set out by organisations including the Society of Radiographers, British Medical Ultrasound Society, the Consortium for the Accreditation of Sonographic Education and Royal College of Radiologists.
Sonographers and radiologists must be registered with an appropriate regulatory council, or if ineligible, must join the voluntary register, The Register of Clinical Technologists. Reporting sonographers and radiologists are accountable to the lead sonographer and lead radiologist.
For operators performing HCC US surveillance in the UK, there is not yet a dedicated, standardised training pathway, although this could improve performance of HCC US surveillance.
As a minimum, it is recommended that practitioners involved in delivering this service participate in regular continuing professional development activities specific to this service, including educational activities (including departmental learning meetings), audit, and quality assurance.
Within any given organisation we recommend that the HCC surveillance examinations are performed by a nominated subset of available operators, who will contribute regularly to this service.
HCC US surveillance can be technically challenging due to the difficulties of visualisation and interpretation in patients with advanced fibrosis, cirrhosis, and/or an elevated body mass index. Successful and effective US imaging requires skills that take time to acquire.
Therefore, it is suggested that surveillance US for HCC is not performed unsupervised by radiology specialist trainees or trainee sonographers.
Statement 11: Imaging during HCC US surveillance examinations should focus on identifying HCC and the complications of liver disease
The primary objective of HCC US surveillance is detection of HCC. HCC US examination should therefore accordingly focus on achieving complete visualisation of the liver parenchyma, within the limitations of the examination.
Secondary objectives include assessing the background liver, documenting features of portal hypertension, identifying ascites, which may indicate decompensation, and vascular complications such as venous thrombosis.
Focused liver US can improve detection of nodules compared to undertaking complete abdominal scanning. Therefore, imaging of the aorta, pancreaticobiliary and genitourinary systems are not considered required as routine during HCC US surveillance.
It is recognised that abnormalities in other structures may be identified incidentally, and the findings should be further clarified with focused scanning and reported as per normal clinical practice.
Statement 12: Documentation of US surveillance examinations should use a standardised, structured report, including LI-RADS US surveillance or equivalent classification
Standardised reporting is preferred by referring clinicians, and a clear classification of the outcome of each surveillance episode enables the report to be actioned by referring clinical teams according to locally agreed pathways.
US surveillance reports should document positive findings, pertinent negative findings, and the degree to which liver visualisation has been compromised by patient factors.
The report should employ a structured free text format and be summarised using the Liver Imaging Reporting and Data System (LI-RADS) US surveillance classification, which provides a categorisation of the US findings and liver visualisation.
Use of the LI-RADS US surveillance classification will also facilitate effective audit and quality assurance of the service. Reports should be available on the PACS and Electronic Patient Record of the referring healthcare provider.
Please note: Positive examinations (LI-RADS US surveillance category US-3, or equivalent) requiring a CT or MRI scan for possible HCC should be immediately notified to referrers using standard radiology departmental processes, in line with Academy of Medical Royal Colleges’ guidance.
Statement 13: Image capture during US surveillance should include standardised image and video capture to enable retrospective review and support interpretation of subsequent imaging examinations
US imaging is a dynamic modality where assessment and diagnosis occur in real time.
During HCC US surveillance, annotated static captures of relevant positive and negative findings should be recorded as in standard clinical practice.
However, these static images represent a fraction of the entire examination. As part of the standard HCC US surveillance protocol, video-captured (‘cine’) sweeps through both lobes of the liver, and through any identified positive findings, should be considered to allow a more detailed and comprehensive record of the US appearances of the liver parenchyma and ultrasound conditions and limitations.
This may prove valuable during retrospective review at future surveillance events, multidisciplinary team discussions and during audit.
As discussed above, availability of US images and US reports on the PACS of the requesting healthcare organisation, typically a secondary care NHS trust, is considered mandatory.
Alternative imaging modalities for hepatocellular carcinoma surveillance
Statement 14: Clinical and imaging teams should consider alternative imaging modalities for hepatocellular carcinoma (HCC) surveillance in patients where technical factors preclude adequate US image acquisition
US image quality is variable and may be significantly compromised in some patients with liver disease.
Sensitivity for detection of HCC falls as image quality deteriorates.
Where US image quality is significantly compromised, alternative imaging should be considered. Alternative surveillance imaging techniques include multiphase intravenous contrast-enhanced CT scans and various comprehensive and abbreviated MRI protocols.
MRI is preferred over CT as a screening test due to the cumulative radiation burden of repeated CT scans.
There is insufficient evidence to recommend a particular MRI protocol for HCC surveillance, although these are currently under evaluation.
The clinical utility and cost-effectiveness of alternative non-US imaging surveillance tests is uncertain. The use of non-US imaging tests carries resource implications as they are inherently more costly than US surveillance, and some non-US imaging tests may be associated with more false positive findings.
Use of non-US imaging resources for HCC US surveillance should be agreed locally between imaging departments and clinicians.
Adoption of standardised pathways for non-US surveillance are recommended to minimise variation between and within organisations.
Quality assurance of ultrasound surveillance
Statement 15: Hepatocellular carcinoma ultrasound (HCC US) surveillance services should undertake regular service evaluation to ensure compliance with these minimum standards for delivering HCC US surveillance
The statements above represent the minimum standards for imaging departments, and compliance with these standards should be confirmed to cancer alliances annually by the nominated lead radiologist and/or sonographer.
Statement 16: HCC US surveillance services should undertake regular audit of adherence with US surveillance
The benefit of HCC US surveillance is only realised with regular attendance; however, compliance with HCC US surveillance protocols is variable.
Services can take steps to promote attendance and adherence to HCC US surveillance (see Statement 3 above, and Hepatocellular carcinoma surveillance: minimum standards, 2024). The lead radiologist and/or sonographer should work with the HCC service-lead to undertake audit of adherence to US surveillance at least every 3 years.
A standardised methodology for auditing adherence with HCC US surveillance services is under development and will be provided as an appendix to this guidance.
Statement 17: HCC US surveillance services should undertake regular quality assurance of US surveillance service delivery
HCC US surveillance should be subject to regular audit and quality assurance.
The overall performance of the HCC US surveillance service depends on identifying patients at risk, maintaining adherence with regular US, and the quality of the US scans performed.
The quality of US scans depends on both patient and operator factors. HCC US surveillance is relatively insensitive, particularly for early HCC in some cohorts of patients, emphasising the need for regular audit and quality assurance to ensure compliance of services with expected performance targets.
Ideally all HCC in at-risk patients would be diagnosed early in patients participating in HCC US surveillance.
Potential indicators of the quality of HCC US surveillance are:
- Quality assessment of obtained clinical HCC US surveillance images.
- Early detection rate: the number of HCCs diagnosed at an early or very early stage in patients participating in HCC US surveillance, expressed as a proportion of all HCCs diagnosed in patients participating in HCC US surveillance.
- Interval cancer rate: the number of interval HCCs diagnosed in patients participating in HCC US surveillance, expressed as a proportion of all HCCs diagnosed in patients participating in HCC US surveillance.
- False positive recall rate: the proportion of patients recalled for additional investigations following an HCC US surveillance episode, who are not subsequently diagnosed with HCC.
A standardised methodology for performing quality assurance of HCC US surveillance services is under development and will be provided as an appendix to this guidance.
Statement 18: There should be dedicated radiology events and learning meetings (REALMs) for the HCC US surveillance service
Practitioners who perform HCC US surveillance should meet at least annually, both to review delivery of the HCC US surveillance service, and to provide an opportunity for reflection and learning from anonymised cases.
This discussion should be led by the lead radiologist and sonographer in line with established guidance for REALM meetings.
In common with other cancer detection programmes, it is suggested that interval cancers of patients in HCC US surveillance should be reviewed at this meeting to share any learning opportunities. Summarised learning points from this meeting should be circulated to stakeholders not able to attend.
Publication reference: PRN01248