A retrospective observational study examining the characteristics and outcomes of tumours diagnosed within and without of the English NHS Bowel Cancer Screening Programme

Abstract

Background:Colorectal cancer is common in England and, with long-term survival relatively poor, improving outcomes is a priority. A major initiative to reduce mortality from the disease has been the introduction of the National Health Service (NHS) Bowel Cancer Screening Programme (BCSP). Combining data from the BCSP with that in the National Cancer Data Repository (NCDR) allows all tumours diagnosed in England to be categorised according to their involvement with the BCSP. This study sought to quantify the characteristics of the tumours diagnosed within and outside the BCSP and investigate its impact on outcomes.Methods:Linkage of the NCDR and BCSP data allowed all tumours diagnosed between July 2006 and December 2008 to be categorised into four groups; screen-detected tumours, screening-interval tumours, tumours diagnosed in non-participating invitees and tumours diagnosed in those never invited to participate. The characteristics, management and outcome of tumours in each category were compared.Results:In all, 76 943 individuals were diagnosed with their first primary colorectal cancer during the study period. Of these 2213 (2.9%) were screen-detected, 623 (0.8%) were screening-interval cancers, 1760 (2.3%) were diagnosed in individuals in non-participating invitees and 72 437 (94.1%) were diagnosed in individuals not invited to participate in the programme due to its ongoing roll-out over the time period studied. Screen-detected tumours were identified at earlier Dukes' stages, were more likely to be managed with curative intent and had significantly better outcomes than tumours in other categories.Conclusion:Screen-detected cancers had a significantly better prognosis than other tumours and this would suggest that the BCSP should reduce mortality from colorectal cancer in England.

Expert opinions and scientific evidence for colonoscopy key performance indicators

“…31 32 Although CRCs are more commonly found in the distal colon (61.5%), 32.7% were found proximal to the splenic flexure, with 15% identified in the caecum or appendix, highlighting the need for complete examination of the colon 33. Previous work has demonstrated higher PCCRC rates in endoscopists with a lower CIR,34 and in colonoscopies which were incomplete 35. PCCRCs were more commonly identified in the right side of the colon 35.…”

“…Previous work has demonstrated higher PCCRC rates in endoscopists with a lower CIR,34 and in colonoscopies which were incomplete 35. PCCRCs were more commonly identified in the right side of the colon 35. A Canadian database analysis of 1260 PCCRCs showed that endoscopists with high caecal intubation rates and those with higher polypectomy rates had significantly lower rates of PCCRC during follow-up 34.…”

Sensitivity and specificity of CT colonography for the detection of colonic neoplasia after positive faecal occult blood testing: systematic review and meta-analysis

“…Whilst extrapolation from such literature is intuitively logical, gFOBt/FIT-positive screenees have such a high prevalence of abnormality that subsequent tests require extremely high sensitivity to achieve an acceptable negative predictive value. Additionally, screen-detected cancers are earlier stage than symptomatic tumours [14], and could be more difficult to detect at CTC. Furthermore, advanced histologic features are more common in gFOBt/FIT-positives, even at equivalent adenoma diameter [15,16].…”

Appearances of screen-detected versus symptomatic colorectal cancers at CT colonography

“…Epidemiological series show that screen-detected cancers are typically of earlier stage than non-screen detected tumours [14] and have superior survival [15]. Similarly, cancers detected by screening CTC are generally of earlier histological stage than the population average [16].…”