National Bowel Cancer Audit

NBOCA (National Bowel Cancer Audit) is a high-profile, collaborative, national clinical audit for bowel cancer, including colon and rectal cancer, run jointly by NHS Digital, the Clinical Effectiveness Unit at the Royal College of Surgeons, and ACPGBI.

National Bowel Cancer Audit

The National Bowel Cancer Audit (NBOCA) now has a standalone website where you can access interactive trust results, reports, news and information about the audit. Search for your trust /site under the Trust results section and you will find the results for your trust /site and be able to compare your trust’s outcomes to all other trusts in England and Wales. 

Visit the NBOCA website

Dataset Changes for 2018-19

The dataset changes for 2018-19 are now live on the Clinical Audit Platform (CAP).

 The updated NBOCA dataset for 2018-19

The main change is the addition of a non-primary record, made up of three COSD data items

  • CR6500: DateOfNonPrimaryCancerPathway
  • CR6520*: RecurrenceOrMetastaticType
  • CR6970: MetastaticSite

*CR6520 includes:

  • 01 Local
  • 02 Regional
  • 03 Distant

The record has been introduced so the audit can collect data on recurrences (not progressions).

Please note:

• Historical recurrence data may be submitted but there must be an associated tumour record in CAP

• Only recurrences relating to the first primary diagnosis of that cancer should be submitted.

Local and loco-regional recurrences that are operated on at a different hospital to the hospital where the surgery for the primary cancer was performed can now be submitted (that is resections for loco-regional recurrence).

These will then be captured through NBOCA as long as the record for the primary tumour was submitted to NBOCA by the hospital carrying out the primary surgery.

2016 NBOCA Report

  • National Bowel Cancer Audit Annual Report 2016

This report is the most up-to-date information from England and Wales on the care and outcomes of bowel cancer patients. Previous National Bowel Cancer Audits concentrated on patients undergoing major resection for their bowel cancer. In 2016 the scope has again widened and now describes patients with early rectal cancers undergoing a local excision and those with too much disease or co-morbidity for a major resection.

Key findings and recommendations 2016

Care pathways

  • Patients diagnosed through the NHS screening programme were more likely to be treated with curative intent than patients diagnosed via other means. 88 per cent of patients diagnosed via the NHS bowel screening programme were treated with curative intent compared to 52 per cent and 69 per cent of patients diagnosed from an emergency presentation and GP referral respectively.
  • 75 per cent of all patients diagnosed with bowel cancer were treated with curative intent. 93 per cent of these patients underwent a major resection and 7 per cent underwent endoscopic or minimally invasive local excision.
  • 25 per cent of patients were treated with palliative intent. 31 per cent of these patients underwent a major resection of the bowel cancer primary or a palliative surgical procedure (the majority being stoma formation or stent).


  • The contribution of the NHS bowel cancer screening programme to the diagnosis of patients with early bowel cancer is demonstrated. All health professionals should be encouraged to actively promote participation in this service to increase service uptake.
  • Clinicians and data managers should prioritise data completeness for: reason for no treatment, performance status, care plan intent and pre-treatment M-stage. This will reduce the proportion of patients who do not undergo a major resection who are unassigned to a treatment pathway and therefore better describe the care and outcomes in this cohort.

Surgical care

  • 90-day survival after major resection continued to improve from 94.6 per cent in 2010-11 to 96.2 per cent in 2014-15. 90-day survival after planned surgery was 98 per cent and after emergency surgery was 88 per cent.
  • Length of hospital stay following surgery is stable. Median length of stay following major bowel cancer resection was seven days. Length of stay was highly variable between regions and the proportion of patients who remain in hospital for longer than ve days after surgery ranged from 59 to 81 per cent across strategic clinical networks.
  • One in ten patients had an unplanned readmission to hospital within 30-days of surgery. There was no more variation between regions in rates of 30-day unplanned readmission than would be expected by chance alone.
  • Over 50 per cent of patients had a laparoscopic bowel cancer resection. The proportion of major resections performed laparoscopically continued to increase year on year. There was no increase in the rate of unplanned conversion to open which has fallen from 9.0 per cent in 2013-14 to 8.5 per cent in 2014-15. The proportion of patients with laparoscopic completed resections ranged from 41 per cent to 68 per cent across strategic clinical networks.


  • Improving the post-operative survival in patients undergoing emergency or urgent bowel cancer resection should remain a clinical priority. The provision of pre-operative resuscitation, adequate theatre access, post-operative critical care, and early colorectal team involvement, including full radiological support and facilities for colonic stenting as a bridge to curative surgery or expediting palliative chemotherapy, is likely
    to improve survival.
  • Efforts to reduce long length of stay may need to be more focused on improving the provision of, and reducing any regional disparity in, community and primary care services (as described in the length of stay short report).
  • Potential delays to discharge, particularly in the elderly population, should be considered pre-operatively, to allow for the provision of community services if required, to reduce the risk of prolonged length of hospital stay.


  • Two-year survival rates for all patients diagnosed with bowel cancer has remained stable at 66 per cent since 2010. There was a large variation in observed two-year patient survival according to strategic clinical network. This variation was more than would be expected by chance alone, however estimates are not adjusted for patient case-mix and there are many potential causes of this variation.
  • The trend of improving two-year survival rates in patients undergoing resection continues, with an increase from 80 per cent in 2009-10 to 82 per cent in 2012-13.


  • Further work is required into investigating regional variation in rates of two-year survival. This is a priority for the audit moving forward and access to the chemotherapy dataset and cause of death data will facilitate this.
  • Patients presenting with stage IV bowel cancer should be referred to multi-disciplinary teams (MDTs) to optimise timing of resection of both the primary tumour and metastases as well as advising on neo-adjuvant and adjuvant treatment.

Rectal cancer

  • 37 per cent of patients undergoing a major resection for rectal cancer received neo-adjuvant radiotherapy. Use of neo-adjuvant radiotherapy in patients undergoing major resection ranged from 29-66 per cent across strategic clinical networks.
  • 83 per cent of rectal cancer patients had a stoma following major resection. 77 per cent of anterior resections were covered by a defunctioning stoma. Within 18 months, 66 per cent of these patients had undergone stoma reversal. There was signi cant variation in the rates of 18-month stoma between both strategic clinical networks and trusts.


  • In the future the audit will correlate radiotherapy use to rates of positive circumferential resection margins and local recurrence in rectal cancer patients undergoing major resection. To facilitate this, clinicians should aim to ensure complete data for circumferential resection margin.
  • Clinicians should ensure that patients undergoing an anterior resection are aware that data suggests that in a signi cant proportion of patients a ‘temporary’ stoma may not be reversed within 18 months.

Further information