Authors' objectives: Colorectal cancer is the fourth most common cancer and the second most common cause of cancer deaths in England. Most cases of colorectal cancer arise from a prior adenomatous polyp in the bowel lining. Colonoscopy is the gold standard investigation for people with symptoms suggestive of colorectal cancer. During a colonoscopy, polyps can be removed or a biopsy can be taken. However, waiting times for colonoscopy can be long and the procedure can be unpleasant. Colon capsule endoscopy may provide an alternative diagnostic procedure to rule out polyps or colorectal cancer. To evaluate the clinical effectiveness, acceptability and cost-effectiveness of colon capsule endoscopy using PillCam COLON 2 for detecting colorectal polyps and colorectal cancer. Colorectal cancer (CRC), which is also known as bowel cancer, is the fourth most common cancer and the second most common cause of cancer deaths in England. Most cases of CRC arise from a prior adenomatous polyp in the lining of the bowel through a process known as the adenoma-carcinoma sequence. Colorectal polyps are very common, and the vast majority of polyps do not turn into cancer. The removal of adenomatous polyps interrupts the adenoma-carcinoma sequence and can reduce the risk of developing CRC and can improve survival. The gold standard diagnostic test for the investigation and diagnosis of colorectal polyps and CRC is colonoscopy (COL). COL allows for the detection and removal of colorectal polyps and, if cancer is suspected, a biopsy can be taken as part of the procedure. However, waiting times for COL are long for some patients. In addition, some people are unwilling or unable to undergo COL and require a different luminal investigation such as computed tomography colonography (CTC). This External Assessment Group (EAG) report assesses the use of colon capsule endoscopy (CCE) using PillCam COLON 2 for the investigation of the bowel through direct visualisation. CCE may provide an alternative to COL or CTC to rule out polyps or CRC or may be used as a filter or triage test prior to COL. The main research question addressed in this report is: Does the use of CCE in adults with lower gastrointestinal signs or symptoms suggestive of CRC, or those due to have post-polypectomy surveillance 3 years after their index COL represent a clinically and cost-effective use of NHS resources, taking into consideration potential COL capacity constraints? The objectives of the assessment are as follows: To conduct a systematic review of the published evidence on the effectiveness and cost-effectiveness of PillCam COLON 2 for detecting colorectal polyps and CRC. To develop a health economic model to assess the cost-effectiveness of PillCam COLON 2 compared with COL and CTC from the perspective of the NHS and Personal Social Services.

Authors' results and conclusions: Among the diagnostic test accuracy studies (11–64% patients ‘in-scope’), for polyps of any size (two studies), ≥ 6 mm (four studies) and ≥ 10 mm (four studies), pooled sensitivities were 0.78 (95% credible interval 0.51 to 0.90), 0.83 (95% credible interval 0.70 to 0.91) and 0.85 (95% credible interval 0.70 to 0.94), respectively. Specificities were 0.60 (95% credible interval 0.27 to 0.88), 0.69 (95% credible interval 0.52 to 0.81) and 0.90 (95% credible interval 0.82 to 0.95), respectively. Among yield studies, colonoscopy was spared in 37–50% of symptomatic patients (three studies). Data on colonoscopy spared in surveillance patients were available from one study; however, these data are confidential and cannot be reported here. In patients unwilling/unable to undergo colonoscopy, colon capsule endoscopy completed 70–98% of incomplete colonoscopies. Patient preference studies indicated general satisfaction with PillCam COLON 2, but some conflicting information on patient preference for colon capsule endoscopy compared to colonoscopy and computed tomography colonography. For colonoscopy-eligible patients, within all three main analysis populations, the External Assessment Group’s model suggests that colon capsule endoscopy is expected to lead to small quality-adjusted life-year losses and higher costs than colonoscopy; hence, colon capsule endoscopy is dominated by colonoscopy. For colonoscopy-ineligible patients, colon capsule endoscopy either dominated by computed tomography colonography or has an incremental cost-effectiveness ratio which is markedly higher than £30,000 per quality-adjusted life-year gained. Despite these findings, colon capsule endoscopy is predicted to lead to substantial reductions in the number of colonoscopies required, particularly for symptomatic patients who are able to undergo colonoscopy. Colon capsule endoscopy is expected to be less effective and more expensive than colonoscopy. However, it could help to free up constrained colonoscopy services, particularly in people with symptoms suggestive of bowel cancer. Database searches retrieved 2376 records, while other search methods retrieved 92 records. After widening of the inclusion criteria, the review included three evidence types: (1) diagnostic test accuracy studies in scope-defined populations (n = 1 study) or mixed populations (n = 5 studies) to provide evidence on the sensitivity and specificity of CCE; (2) diagnostic yield studies to provide estimates of underlying disease prevalence and capacity spared (n = 4 in scope-defined populations; n = 7 in mixed populations with incomplete COL or who refused COL), and (3) patient preference studies (n = 4 studies). In total, 19 studies reported across 24 sources were included. Two studies contributed data to two evidence types (yield studies in the correct population and patient preference). Diagnostic test accuracy studies One diagnostic test accuracy study conducted in a scope-defined symptomatic population was included. Sensitivity and specificity for clinically significant polyps were calculated by the EAG to be 100% [95% confidence interval (CI) 0.65 to 1.00] and 98% (95% CI 0.91 to 1.00), respectively, but the study was small (n = 66, seven significant polyps) and it probably did not include the full spectrum of relevant symptomatic patients. Five diagnostic test accuracy studies conducted in mixed populations were also included. The proportion of patients within the scope of the assessment in these studies ranged from 11% to 64%. Four studies reported data suitable for pooling in the statistical synthesis. Pooled sensitivity and specificity for polyps of any size (n = 2) were 0.78 [95% credible interval (CrI) 0.51 to 0.90] and 0.60 (95% CrI 0.27 to 0.88), respectively; for polyps ≥ 6 mm (n = 4) 0.83 (95% CrI 0.70 to 0.91) and 0.69 (95% CrI 0.52 to 0.81), respectively; and for ≥ 10 mm (n = 4) 0.85 (95% CrI 0.70 to 0.94) and 0.90 (95% CrI 0.82 to 0.95), respectively. Data on the diagnostic test accuracy for adenomas were limited to one small study (n = 89) with potentially poor generalisability to the decision problem due to the low proportion of patients in the study who were within the scope of the assessment (11%).

Authors' methods: A systematic review searched six bibliographic databases and eight conference proceedings in August 2024. Studies of PillCam COLON 2 in symptomatic or polyp surveillance patients were included if they were randomised controlled trials, or if they reported data on diagnostic test accuracy, yield or patient preference. Bayesian pooling of sensitivity and specificity was performed. The economic analysis included a review of existing models and development of an independent model to assess the cost-effectiveness of colon capsule endoscopy versus colonoscopy and computed tomography colonography in three main populations (symptomatic patients with a faecal immunochemical test score of 10–100 μg/g, symptomatic faecal immunochemical test

Project Status: Completed

URL for project: https://www.journalslibrary.nihr.ac.uk/programmes/hta/NIHR136010

Year Published: 2026

URL for published report: https://www.journalslibrary.nihr.ac.uk/hta/GJPT1820

URL for additional information: English

English language abstract: An English language summary is available

Publication Type: Full HTA

Country: England, United Kingdom

DOI: 10.3310/GJPT1820

Organisation Name: NIHR Health Technology Assessment programme

Contact Address: NIHR Journals Library, National Institute for Health and Care Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science Park, Southampton SO16 7NS, UK

Contact Name: journals.library@nihr.ac.uk

Contact Email: journals.library@nihr.ac.uk