Screen-detected colorectal cancers are associated with an improved outcome compared with stage-matched interval cancers.

BACKGROUND: Colorectal cancers (CRCs) detected through the NHS Bowel Cancer Screening Programme (BCSP) have been shown to have a more favourable outcome compared to non-screen-detected cancers. The aim was to identify whether this was solely due to the earlier stage shift of these cancers, or whether other factors were involved. METHODS: A combination of a regional CRC registry (Northern Colorectal Cancer Audit Group) and the BCSP database were used to identify screen-detected and interval cancers (diagnosed after a negative faecal occult blood test, before the next screening round), diagnosed between April 2007 and March 2010, within the North East of England. For each Dukes' stage, patient demographics, tumour characteristics, and survival rates were compared between these two groups. RESULTS: Overall, 322 screen-detected cancers were compared against 192 interval cancers. Screen-detected Dukes' C and D CRCs had a superior survival rate compared with interval cancers (P=0.014 and P=0.04, respectively). Cox proportional hazards regression showed that Dukes' stage, tumour location, and diagnostic group (HR 0.45, 95% CI 0.29-0.69, P<0.001 for screen-detected CRCs) were all found to have a significant impact on the survival of patients. CONCLUSIONS: The improved survival of screen-detected over interval cancers for stages C and D suggest that there may be a biological difference in the cancers in each group. Although lead-time bias may have a role, this may be related to a tumour's propensity to bleed and therefore may reflect detection through current screening tests.

Management of complex colonic polyps in the English Bowel Cancer Screening Programme.

BACKGROUND: Large sessile or flat colonic polyps, defined as polyps at least 20 mm in size, are difficult to treat endoscopically and may harbour malignancy. The aim of this study was to describe their current management to provide insight into optimal management. METHODS: This retrospective observational study identified patients with large sessile or flat polyps detected in the English Bowel Cancer Screening Programme between 2006 and 2009. Initial therapeutic modality (surgical or endoscopic), subsequent management and outcomes were recorded. The main outcome measures analysed were: presence of malignancy, need for surgical treatment, complications, and residual or recurrent polyp at 12 months. RESULTS: In total, 557 large sessile or flat polyps with benign appearance or initial histology were identified in 557 patients. Some 436 (78.3 per cent) were initially managed endoscopically and 121 (21.7 per cent) were managed surgically from the outset. Seventy of those initially treated endoscopically subsequently required surgery owing to the presence of malignancy (19) or not being suitable for further endoscopic management (51). Residual or recurrent polyp was present at 12 months in 26 (6.0 per cent) of 436 patients managed endoscopically. There was wide variation between centres in the use of surgery as a primary therapy, ranging from 7 to 36 per cent. Endoscopic complications included bleeding in 13 patients (3.0 per cent) and perforation in two (0.5 per cent). CONCLUSION: Management of large sessile or flat colonic polyps is safe and effective in the English Bowel Cancer Screening Programme. Wide variation in the use of surgery suggests a need for standardized management algorithms. Presented to a meeting of the British Society of Gastroenterology, Birmingham, U.K., March 2011.

Outcome of 12-month surveillance colonoscopy in high-risk patients in the National Health Service Bowel Cancer Screening Programme.

AIM: Current British guidelines recommend surveillance colonoscopy at 12 months for individuals found to have five or more adenomas, or three or more adenomas of which at least one is ≥ 1 cm in size. This study describes the yield of surveillance colonoscopy in this group and explores patient and clinical factors that may be associated with the presence of advanced adenomas or cancer at surveillance. METHOD: Data were retrieved from the national database of the National Health Service Bowel Cancer Screening Programme. The detection of advanced colonic neoplasia (ACN, cancer or advanced adenoma) was used as the main outcome variable. Multivariable analysis was used to analyse relationships between patient factors (age, gender, body mass index, smoking and alcohol use) and clinical findings (number, size and nature of adenomas detected during index colonoscopy) with the outcome variable. RESULTS: One-thousand, seven-hundred and sixty individuals were included in the study. The yield of ACN at 12-month surveillance was 6.6% (116/1760), of which 14/1760 (0.8%) had colorectal cancer. Nine (64.3%) of these 14 cancers were Dukes A at diagnosis. The presence of a villous adenoma or a right-sided adenoma at screening colonoscopy was associated with ORs of 1.98 (95% CI: 1.11-3.53, P = 0.012) and 1.76 (95% CI: 1.13-2.74, P = 0.020), respectively, for detection of ACN at surveillance. CONCLUSION: Twelve-month surveillance colonoscopy is necessary in this group of patients. The presence of villous or proximal lesions at baseline is associated with increased risk of ACN at surveillance. Site and histological type of baseline lesions may be relevant for determining the surveillance interval.

Longer mean colonoscopy withdrawal time is associated with increased adenoma detection: evidence from the Bowel Cancer Screening Programme in England.

BACKGROUND AND STUDY AIMS: Increasing colonoscopy withdrawal time (CWT) is thought to be associated with increasing adenoma detection rate (ADR). Current English guidelines recommend a minimum CWT of 6 minutes. It is known that in the Bowel Cancer Screening Programme (BCSP) in England there is wide variation in CWT. The aim of this observational study was to examine the relationship between CWT and ADR. PATIENTS AND METHODS: The study examined data from 31 088 colonoscopies by 147 screening program colonoscopists. Colonoscopists were grouped in four levels of mean CWT ( < 7, 7 - 8.9, 9 - 10.9, and ≥ 11 minutes). Univariable and multivariable analysis (binary logistic and negative binomial regression) were used to explore the relationship between CWT, ADR, mean number of adenomas and number of right-sided and advanced adenomas. RESULTS: In colonoscopists with a mean CWT < 7 minutes, the mean ADR was 42.5 % compared with 47.1 % in the ≥ 11-minute group (P < 0.001). The mean number of adenomas detected per procedure increased from 0.77 to 0.94, respectively (P < 0.001). The increase in adenoma detection was mainly of subcentimeter or proximal adenomas; there was no increase in the detection of advanced adenomas. Regression models showed an increase in ADR from 43 % to 46.5 % for mean CWT times ranging from 6 to 10 minutes. CONCLUSIONS: This study demonstrates that longer mean withdrawal times are associated with increasing adenoma detection, mainly of small or right-sided adenomas. However, beyond 10 minutes the increase in ADR is minimal. Mean withdrawal times longer than 6 minutes are not associated with increased detection of advanced adenomas. Withdrawal time remains an important quality metric of colonoscopy.

Comparison of screen-detected and interval colorectal cancers in the Bowel Cancer Screening Programme.

BACKGROUND: The NHS Bowel Cancer Screening Programme (BCSP) offers biennial faecal occult blood testing (FOBt) followed by colonoscopy after positive results. Colorectal cancers (CRCs) registered with the Northern Colorectal Cancer Audit Group database were cross-referenced with the BCSP database to analyse their screening history. METHODS: The CRCs in the screening population between April 2007 and March 2010 were identified and classified into four groups: control (diagnosed before first screening invite), screen-detected, interval (diagnosed between screening rounds after a negative FOBt), and non-uptake (declined screening). Patient demographics, tumour characteristics and survival were compared between groups. RESULTS: In all, 511 out of 1336 (38.2%) CRCs were controls; 825 (61.8%) were in individuals invited for screening of which 322 (39.0%) were screen detected, 311 (37.7%) were in the non-uptake group, and 192 (23.3%) were interval cancers. Compared with the control and interval cancer group, the screen-detected group had a higher proportion of men (P=0.002, P=0.003 respectively), left colon tumours (P=0.007, P=0.003), and superior survival (both P<0.001). There was no difference in demographics, tumour location/stage, or survival between control and interval groups. CONCLUSION: The FOBt is better at detecting cancers in the left colon and in men. The significant numbers of interval cancers weren't found to have an improved outcome compared with the non-screened population.

Achieving high quality colonoscopy: using graphical representation to measure performance and reset standards.

AIM: Completeness and thoroughness of colonoscopy are measured by the caecal intubation rate (CIR) and the adenoma detection rate (ADR). National standards are ≥ 90% and ≥ 10% respectively. Variability in CIR and ADR have been demonstrated but comparison between individuals and units is difficult. We aimed to assess the performance of colonoscopy in endoscopy units in the northeast of England. METHOD: Data on colonoscopy performance and sedation use were collected over 3 months from 12 units. Colonoscopies performed by screening colonoscopists were included for the CIR only. Funnel plots with upper and lower 95% confidence limits for CIR and ADR were created. RESULTS: CIR was 92.5% (n = 5720) and ADR 15.9% (n = 4748). All units and 128 (99.2%) colonoscopists were above the lower limit for CIR. All units achieved the ADR standard with 10 above the upper limit. Ninety-nine (76.7%) colonoscopists were above 10%, 16 (12.4%) above the upper limit and 7 (5.4%) below the lower limit. Median medication doses were 2.2 mg midazolam, 29.4 mg pethidine and 83.3 µg fentanyl. In all, 15.1% of colonoscopies were unsedated. Complications were bleeding (0.10%) and perforation (0.02%). There was one death possibly related to bowel preparation. CONCLUSION: Results indicate that colonoscopies are performed safely and to a high standard. Funnel plots can highlight variability and areas for improvement. Analyses of ADR presented graphically around the global mean suggest that the national standard should be reset at 15%.

Bowel cancer screening is safe, detects earlier stage cancer and adenomas in 50% of cases: experience of the prevalent round of screening from two first wave centres in the North East of England.

OBJECTIVE: The NHS Bowel Cancer Screening Programme (BCSP) began roll-out in 2006 aiming to reduce cancer mortality through detection at an earlier stage. We report results from the prevalent round of screening at two first wave centres and compare with the UK pilot study. DESIGN: This is a service evaluation study. Data were collected prospectively for all individuals undergoing faecal occult blood testing (FOBt) and colonoscopy including: uptake and outcomes of FOBt, colonoscopic performance, findings, histological data and complications. Continuous data were compared using a two-tailed test of two proportions. SETTING: The South of Tyne and Tees Bowel Cancer Screening centres. PATIENTS: Participants of the BCSP. MAIN OUTCOME MEASURES: 1) Colonoscopy Quality Assurance and 2) Cancer stage shift. RESULTS: 195,772 individuals were invited to participate. Uptake was 54% and FOBt positivity 1.7%. 1524 underwent colonoscopy with caecal intubation in 1485 (97%). 180 (12%) cancers were detected. Dukes stages were: 76 (42%) A; 47 (26%) B; 47 (26%) C; 8 (4%) D and 2 (1%) unknown. This demonstrates a significantly earlier stage at diagnosis compared with data from 2867 non-screening detected cancers (p<0.001). Adenomas were detected in 758 (50%). One perforation occurred (0.07%) and two intermediate bleeds requiring transfusion only (0.12%). Both caecal intubation and adenoma detection were significantly higher than in the UK pilot study (p<0.001). CONCLUSIONS: The prevalent round of screening demonstrates a high adenoma and cancer detection rate and significantly earlier stage at diagnosis. Complications were few providing reassurance regarding safety. Efforts are required to improve uptake.