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Post Colonoscopy Colorectal Cancer Audit

The audit follows the recommendation made by the World Endoscopy Organisation (WEO) to review PCCRCs occurring within 48 months of a colonoscopy that did not show cancer [1]. For practical purposes, a 6-48 month window has been chosen. More than 1,500 cancers diagnosed each year have been preceded by a colonoscopy that did not show cancer in this window. A recent British study suggests up to 80% of these are potentially avoidable [2]. The ultimate goal of the audit is to reduce PCCRCs following colonoscopies performed from 2022 onwards by 50%.

PCCRC rates are proposed as a key quality indicator of colonoscopy by the BSG, and the JAG requires units to audit them to maintain accreditation. It has, however, been very difficult for services to identify cases reliably, not least because the cancer is often diagnosed in a different trust (up to 20% of PCCRCs in some urban areas).

To help services identify and audit PCCRCs, a National reporting system has been developed. PCCRCs are identified using central databases and the trust where the colonoscopy was performed notified of cases via a secure portal. The portal has an audit tool designed to help determine the most plausible explanation for the PCCRC as defined by the WEO [1]. The BSG, the JAG, ACPGBI, and NHSE support this audit. The JAG has recently reduced the burden of audit for accreditation to allow time to review PCCRCs.

In the initial phase, up to 25 PCCRCs will be uploaded for each trust. We anticipate a further upload of PCCRCs three times a year as new cases are captured with refresh of national database linkages.

Endoscopy team leaders will be encouraged to discuss each case, together with the most plausible explanation, with individual endoscopists and present an overview of lessons learned anonymously to the wider team. It is extremely important to stress that the sample size of cases will be far too small to draw conclusions about the competence of individual endoscopists. Having said this, judging by the published audit [2], there will be important lessons to learn for individual endoscopists and referrers, and the service as a whole. The overall intention is to find areas in need of improvement and act on them, NOT to find fault.


  1. Rutter MD, Beintaris I, Valori R, et al. World Endoscopy Organization Consensus Statements on Post-Colonoscopy and Post-Imaging Colorectal Cancer. Gastroenterology 2018;155:909-925.e3. doi:10.1053/j.gastro.2018.05.038
  2. Anderson R, Burr NE, Valori R. Causes of Post-colonoscopy Colorectal Cancers Based on World Endoscopy Organization System of Analysis. Gastroenterology Published Online First: January 2020. doi:10.1053/j.gastro.2019.12.031


Roland Valori

Consultant Gastroenterologist

Clinical Lead for the English National PCCRC project

National PCCRC audit – Frequently asked questions

How will PCCRCs be identified?

The PCCRCs are identified following linkage of HES, bowel cancer screening, and cancer registry datasets. To find the most recent PCCRCs, we are identifying cancers in the registry prior to final sign off.


How will my unit be notified of the audit?

The clinical leads of each unit will be given sign on instructions. It is expected one clinical lead for each trust for the audit will be nominated. This lead can nominate two other individuals to have access to the audit portal.


What if there are several endoscopy units in my trust?

Cases are identified on a trust, not unit basis.


What is the process?

In the audit portal, there will be a list of patients who have had PCCRCs that had their index colonoscopy in your trust. There will be patient identifiable information (NHS number). Selecting one of these cases will lead to the audit template. The audit template has been designed to be self-explanatory with information icons where necessary. In addition, there will be a variety of supporting documents in the portal to help communication and implementation. These documents have been informed by experience in ten pilot sites. They will include explanatory documents, and draft emails and presentations to share with colleagues and the trust information governance team.


Will the audit be time-consuming?

The time required to review a case depends on your trust information systems and whether you have electronic capture of endoscopic images. If you have to review large sets of case notes, and search for Polaroid images, it will take some time to answer all the audit questions. However, once you have all the relevant information, completing the template is quick. The benefit of identifying areas in need of improvement will hugely outweigh the time it takes to review cases. Some of these will be quick wins, but other areas of improvement such as optimising IBD surveillance will be challenging.


What happens if the PCCRC is diagnosed in a different trust?

If this happens, the trust where the PCCRC was diagnosed will be notified of the PCCRC first, but will not know where the index colonoscopy was performed. They will be asked to provide a small dataset of cancer details. Once these have been completed the case will appear on the list of patients on the index colonoscopy trust site. These cancer details should be readily available and this task should not be at all difficult.


Do I need to seek approval from Information Governance (IG) or Caldicott guardian?

No. All the necessary approvals have been obtained from Public Health England including the PHE Caldicott Guardian. However, we recommend you inform your trust IG team of the audit. The audit is likely to identify cases that require discharge of Duty of Candour and for this reason, we recommend you also inform and work with your trust patient safety team from the outset of the audit.

Do colonoscopists need to be concerned about the audit?

Virtually all colonoscopists, even the very best, will have PCCRCs if they do enough colonoscopy, especially if they scope patients at high risk of PCCRCs. In many instances, the PCCRC will be considered unavoidable and in others it will not be clear whether the PCCRC arose from poor quality colonoscopy (largely because we don’t know the natural history of colorectal cancer).  Inevitably, there will be some cases where it will be evident that the procedure was suboptimal and questions might be raised about the competence of individual endoscopists. However, the sample size will be far too small to make any judgements about competence, and as such, individual endoscopists should not be concerned that their competence is being questioned. The case will need to be reviewed in the context of other performance data such as polyp detection rates, caecal intubation rates, withdrawal times, photo-documentation, and decision-making. Individuals should regard PCCRC review as just another source of information about performance.


Do I have to participate in this audit?

It is not mandatory to participate in the audit, but review of PCCRCs is a key BSG quality indicator and a requirement to maintain accreditation. Increasingly, the CQC will be using proxy evidence to rate trusts and failure to participate in audits, particularly ones like this, will be viewed unfavourably by the CQC. It is hoped that endoscopy teams will appreciate the clear benefit to patients of participation in the audit and that this will be the prime motivation to take part.


Will my data be used?

The organisers of the project have permission from the Office for Data Release of PHE to collect and present aggregated data. The intention here is to develop a robust evidence base of factors that lead to PCCRCs. At the moment, there are very small samples of PCCRC review that may not represent the ‘real world’. It is anticipated that a large sample from a national audit will provide a high level of confidence of factors that lead to PCCRC, at least in systems like the NHS.  As the audit progresses, the outputs will be shared with all trusts. It is expected they will be of use to other jurisdictions that are not able to collect such data.  It is expected that during the process of assessment for the purposes of achieving or maintaining accreditation, the JAG may request sight of key issues arising from the audit and importantly evidence they are being addressed. There will be no sharing of patient or endoscopist level data.