Quality assurance in flexible sigmoidoscopy: medical and nonmedical endoscopists

Factors affecting adenoma detection rate in a national flexible sigmoidoscopy screening programme: a retrospective analysis

BACKGROUND

A national colorectal cancer screening programme started in England in 2013, offering one-off flexible sigmoidoscopy to all men and women aged 55 years in addition to the biennial faecal occult blood testing programme offered to all individuals aged 60-74 years. We analysed data from six pilot flexible sigmoidoscopy screening centres to examine factors affecting the adenoma detection rate (ADR).

METHODS

We did a retrospective analysis of flexible sigmoidoscopy screening procedures performed in individuals aged 55 years at six pilot sites in England as part of the National Health Service Bowel Scope Screening programme. ADR (number of procedures in which at least one adenoma was removed or biopsied, divided by total number of procedures) was calculated for each site and each endoscopist. Multiple regression models were used to examine the variation in ADR with withdrawal time and extent of examination, and the effect of other factors including comfort and bowel preparation on extent of examination.

FINDINGS

The analysis included 8256 procedures done between May 7, 2013, and May 6, 2014. The overall ADR was 9·1% (95% CI 8·5-9·8; 755 of 8256 procedures), varying from 7·4% (6·2-8·9) to 11·0% (9·1-13·4) by screening centre. The ADR was 11·5% (95% CI 10·6-12·5; 493 of 4299 procedures) in men and 6·6% (5·9-7·4; 262 of 3957 procedures) in women (p<0·0001). On multivariate analysis, factors associated with adenoma detection were male sex (relative risk 1·69, 95% CI 1·46-1·95; p<0·0001) and a withdrawal time from the splenic flexure of at least 3·25 min in negative procedures (1·22, 1·00-1·48; p=0·045). However, increasing the withdrawal time to 4·0 min or more did not increase the likelihood of adenoma detection (1·22, 0·99-1·51; p=0·057). Procedures not reaching the splenic flexure were associated with lower chance of adenoma detection (eg, 0·77, 0·66-0·91; p=0·0015 for procedures reaching the descending colon), but there was no additional benefit associated with reaching the transverse colon (0·83, 0·67-1·02; p=0·069). Women (0·83, 0·80-0·87; p<0·0001), individuals with adequate (0·79, 0·76-0·83; p<0·0001) or poor (0·58, 0·51-0·67; p<0·0001) bowel preparation (compared with good bowel preparation), and those with mild (0·82, 0·76-0·88; p<0·0001) or moderate or severe (0·58, 0·51-0·66; p<0·0001) discomfort (compared with no discomfort) were less likely to have a procedure reaching the splenic flexure.

INTERPRETATION

Key performance indicators for flexible sigmoidoscopy screening should be defined, including standards for insertion and withdrawal times, optimal depth, and bowel preparation. ADR could be improved by recommending a withdrawal time from the splenic flexure of at least 3·25 min (ideally 3·5-4·0 min).

FUNDING

None.

Non-physician endoscopists: A systematic review

AIM: To examine the available evidence on safety, competency and cost-effectiveness of nursing staff providing gastrointestinal (GI) endoscopy services.

METHODS: The literature was searched for publications reporting nurse endoscopy using several databases and specific search terms. Studies were screened against eligibility criteria and for relevance. Initial searches yielded 74 eligible and relevant articles; 26 of these studies were primary research articles using original datasets relating to the ability of non-physician endoscopists. These publications included a total of 28883 procedures performed by non-physician endoscopists.

RESULTS: The number of publications in the field of non-specialist gastrointestinal endoscopy reached a peak between 1999 and 2001 and has decreased thereafter. 17/26 studies related to flexible sigmoidoscopies, 5 to upper GI endoscopy and 6 to colonoscopy. All studies were from metropolitan centres with nurses working under strict supervision and guidance by specialist gastroenterologists. Geographic distribution of publications showed the majority of research was conducted in the United States (43%), the United Kingdom (39%) and the Netherlands (7%). Most studies conclude that after appropriate training nurse endoscopists safely perform procedures. However, in relation to endoscopic competency, safety or patient satisfaction, all studies had major methodological limitations. Patients were often not randomized (21/26 studies) and not appropriately controlled. In relation to cost-efficiency, nurse endoscopists were less cost-effective per procedure at year 1 when compared to services provided by physicians, due largely to the increased need for subsequent endoscopies, specialist follow-up and primary care consultations.

CONCLUSION: Contrary to general beliefs, endoscopic services provided by nurse endoscopists are not more cost effective compared to standard service models and evidence suggests the opposite. Overall significant shortcomings and biases limit the validity and generalizability of studies that have explored safety and quality of services delivered by non-medical endoscopists.

Is whole colonic imaging necessary for symptoms of change in bowel habit and/or rectal bleeding?

AIM

Following the introduction of a 2-week-wait (2ww) cancer pathway, many units are triaging patients with change in bowel habit (CIBH) and/or rectal bleeding (RB) straight to colonoscopy. Evidence suggests that right-sided colonic cancer does not present with these symptoms, hence imaging the left colon only is satisfactory. If this were substantiated, patients could be offered a flexible sigmoidoscopy (FS) alone. This study aimed to review presenting symptoms of patients diagnosed with a right-sided colonic malignancy and assess whether their tumours would be missed based on this practice.

METHOD

This is a retrospective analysis of patients who underwent curative resection for a proximal colonic malignancy over a 4-year period. Two-week-wait referral proforma and case notes were analysed for mode of presentation.

RESULTS

Of 206 elective right hemicolectomies performed, 20/206 (9.7%) patients presented in the absence of either iron deficiency anaemia or palpable abdominal mass. Twelve patients had polyposis identified in the left colon and eight patients had no left-sided colonic pathology. One patient had a strong family history of colon cancer (two first-degree relatives) in the group absent of left-sided pathology.

CONCLUSION

Twelve patients who had left-sided polyposis and one patient with a strong family history would have undergone whole colonic imaging based on current colorectal cancer management guidelines. The remaining seven patients with right-sided cancer would have been missed if FS were the only investigation used. Patients presenting on the 2ww with symptoms of a CIBH and/or RB can be adequately investigated with a FS with a 3% chance of missing a proximal cancer.