Edward Dadswell

Computed tomographic colonography versus colonoscopy for investigation of patients with symptoms suggestive of colorectal cancer (SIGGAR): a multicentre randomised trial

BACKGROUND Colonoscopy is the gold-standard test for investigation of symptoms suggestive of colorectal cancer; computed tomographic colonography (CTC) is an alternative, less invasive test. However, additional investigation after CTC is needed to confirm suspected colonic lesions, and this is an important factor in establishing the feasibility of CTC as an alternative to colonoscopy. We aimed to compare rates of additional colonic investigation after CTC or colonoscopy for detection of colorectal cancer or large (≥10 mm) polyps in symptomatic patients in clinical practice. METHODS This pragmatic multicentre randomised trial recruited patients with symptoms suggestive of colorectal cancer from 21 UK hospitals. Eligible patients were aged 55 years or older and regarded by their referring clinician as suitable for colonoscopy. Patients were randomly assigned (2:1) to colonoscopy or CTC by computer-generated random numbers, in blocks of six, stratified by trial centre and sex. We analysed the primary outcome-the rate of additional colonic investigation-by intention to treat. The trial is an International Standard Randomised Controlled Trial, number 95152621. FINDINGS 1610 patients were randomly assigned to receive either colonoscopy (n=1072) or CTC (n=538). 30 patients withdrew consent, leaving for analysis 1047 assigned to colonoscopy and 533 assigned to CTC. 160 (30.0%) patients in the CTC group had additional colonic investigation compared with 86 (8.2%) in the colonoscopy group (relative risk 3.65, 95% CI 2.87-4.65; p<0.0001). Almost half the referrals after CTC were for small (<10 mm) polyps or clinical uncertainty, with low predictive value for large polyps or cancer. Detection rates of colorectal cancer or large polyps in the trial cohort were 11% for both procedures. CTC missed 1 of 29 colorectal cancers and colonoscopy missed none (of 55). Serious adverse events were rare. INTERPRETATION Guidelines are needed to reduce the referral rate after CTC. For most patients, however, CTC provides a similarly sensitive, less invasive alternative to colonoscopy. FUNDING NIHR Health Technology Assessment Programme, NIHR Biomedical Research Centres funding scheme, Cancer Research UK, EPSRC Multidisciplinary Assessment of Technology Centre for Healthcare, and NIHR Collaborations for Leadership in Applied Health Research and Care.

Computed tomographic colonography versus barium enema for diagnosis of colorectal cancer or large polyps in symptomatic patients (SIGGAR): a multicentre randomised trial

BACKGROUND Barium enema (BE) is widely available for diagnosis of colorectal cancer despite concerns about its accuracy and acceptability. Computed tomographic colonography (CTC) might be a more sensitive and acceptable alternative. We aimed to compare CTC and BE for diagnosis of colorectal cancer or large polyps in symptomatic patients in clinical practice. METHODS This pragmatic multicentre randomised trial recruited patients with symptoms suggestive of colorectal cancer from 21 UK hospitals. Eligible patients were aged 55 years or older and regarded by their referring clinician as suitable for radiological investigation of the colon. Patients were randomly assigned (2:1) to BE or CTC by computer-generated random numbers, in blocks of six, stratified by trial centre and sex. We analysed the primary outcome-diagnosis of colorectal cancer or large (≥10 mm) polyps-by intention to treat. The trial is an International Standard Randomised Controlled Trial, number 95152621. FINDINGS 3838 patients were randomly assigned to receive either BE (n=2553) or CTC (n=1285). 34 patients withdrew consent, leaving for analysis 2527 assigned to BE and 1277 assigned to CTC. The detection rate of colorectal cancer or large polyps was significantly higher in patients assigned to CTC than in those assigned to BE (93 [7.3%] of 1277 vs 141 [5.6%] of 2527, relative risk 1.31, 95% CI 1.01-1.68; p=0.0390). CTC missed three of 45 colorectal cancers and BE missed 12 of 85. The rate of additional colonic investigation was higher after CTC than after BE (283 [23.5%] of 1206 CTC patients had additional investigation vs 422 [18.3%] of 2300 BE patients; p=0.0003), due mainly to a higher polyp detection rate. Serious adverse events were rare. INTERPRETATION CTC is a more sensitive test than BE. Our results suggest that CTC should be the preferred radiological test for patients with symptoms suggestive of colorectal cancer. FUNDING NIHR Health Technology Assessment Programme, NIHR Biomedical Research Centres funding scheme, Cancer Research UK, EPSRC Multidisciplinary Assessment of Technology Centre for Healthcare, and NIHR Collaborations for Leadership in Applied Health Research and Care.

Patient acceptability of CT colonography compared with double contrast barium enema: results from a multicentre randomised controlled trial of symptomatic patients

ObjectivesTo determine patient acceptability of barium enema (BE) or CT colonography (CTC).MethodsAfter ethical approval, 921 consenting patients with symptoms suggestive of colorectal cancer who had been randomly assigned and completed either BE (N = 606) or CTC (N = 315) received a questionnaire to assess experience of the clinical episode including bowel preparation, procedure and complications. Satisfaction, worry and physical discomfort were assessed using an adapted version of a validated acceptability scale. Non-parametric methods assessed differences between the randomised tests and the effect of patient characteristics.ResultsPatients undergoing BE were significantly less satisfied (median 61, interquartile range [IQR] 54–67 vs. median 64, IQR 56–69; p = 0.003) and experienced more physical discomfort (median 40, IQR 29–52 vs. median 35.5, IQR 25–47; p < 0.001) than those undergoing CTC. Post-test, BE patients were significantly more likely to experience ‘abdominal pain/cramps’ (68% vs. 57%; p = 0.007), ‘soreness’ (57% vs. 37%; p < 0.001), ‘nausea/vomiting’ (16% vs. 8%; p = 0.009), ‘soiling’ (31% vs. 23%; p = 0.034) and ‘wind’ (92% vs. 84%; p = 0.001) and in the case of ‘wind’ to also rate it as severe (27% vs. 15%; p < 0.001).ConclusionCTC is associated with significant improvements in patient experience. These data support the case for CTC to replace BE.

PWE-344 Retrospective cohort study to examine the frequency of follow-up for patients with intermediate grade colorectal adenomas (ia study)

Introduction Background UK and USA surveillance guidelines recommend 3-yearly surveillance for intermediate and higher-risk groups, respectively. To date, no study has examined surveillance needs in this group, which comprises nearly half of patients with adenomas. Aims and objective(s) To identify the optimum frequency of surveillance and assess whether there is substantial heterogeneity in risk; to examine the risks of cancer and advanced adenomas (AA). Method Design and Setting Retrospective, multi-centre cohort study, involving a hospitals dataset drawn from 17 UK NHS hospitals (n = 11,944), and three pooled screening cohorts (n = 2,353). Subjects Patients with intermediate-grade adenoma (s) defined as having 3–4 small adenomas (<10 mm), or 1–2 adenomas, at least one of which is large (≥10 mm). Primary outcomes AA and colorectal cancer (CRC) detected at the first and second follow-up visits, and CRC incidence after baseline and first follow-up. Results Among 4,608 patients with follow-up in the hospital dataset, an increase in interval length was associated with a significant increased odds of AA and CRC at the first follow-up (p < 0.001). Of 1,635 patients attending a second follow-up, a significant association was also found between interval and odds of advanced neoplasia at the second follow-up (p = 0.026). Among 11,944 patients, 168 CRCs occurred during 81,442 person-years of observation time after baseline (206 per 100,000 pyrs, 95% CI 177–240). A single surveillance visit conferred a considerable reduction in risk of CRC after baseline (p = 0.0001). Other independent predictors of CRC were used to devise higher (HIR) and lower (LIR) intermediate risk subgroups, between which there was substantial heterogeneity in risk. A single surveillance exam lowered risk in the HIR subgroup (n = 9,265); however the benefit of surveillance in the LIR (n = 2,679) was unclear. 1,828 intermediate risk patients with at least one follow-up in the pooled screening cohorts were younger, on average, than the hospital cohort. No association was found between findings at follow-up and interval, however, there was evidence of the benefit of surveillance and the LIR and HIR subgroups derived from the hospital dataset were discriminant of CRC risk in the screening participants. Conclusion A surveillance interval of three to four years seems suitable for the majority of intermediate-risk patients. Surveillance lowers future risk of CRC in intermediate risk patients; however there was heterogeneity in risk and surveillance needs, which suggested that a single follow-up may suffice in certain intermediate-risk patients. Disclosure of interest None Declared.

Cost-Effectiveness Analysis Of Computed Tomographic Colonography Versus Double Contrast Barium Enema For Investigation Of Patients With Symptoms Of Colorectal Cancer: Economic Evaluation Alongside The Siggar Trial.

CN1 TREATMENT STRATEgIES FOR STAgE IB CERvICAl CANCER: A COSTEFFECTIvENESS ANAlySIS Lee JY, Kim JW Seoul National University, Seoul, South Korea Objectives: To access the cost-effectiveness of two common strategies and alternative triage strategy for patients with stage IB cervical cancer. MethOds: A Markov state transition model was constructed to compare three strategies: (1) radical hysterectomy followed by tailored adjuvant therapy (RH+TA); (2) primary chemoradiation (pCCRT); (3) Triage strategy, in which patients without risk in preoperative MRI undergo primary surgery and those with any risk factors in MRI undergo primary CCRT. All relevant literatures were identified to extract the probability data. Direct medical costs were estimated from Korean National Health Insurance database. Strategies were compared using incremental cost per year of life saved (YLS). Results: RH+TA strategy was the least expensive strategy. Although pCCRT strategy had similar outcomes, pCCRT strategy was more expensive than RH+TA (

Patient Acceptability and Psychologic Consequences of CT Colonography Compared with Those of Colonoscopy: Results from a Multicenter Randomized Controlled Trial of Symptomatic Patients

10,945 vs.

Computed tomographic colonography versus colonoscopy or barium enema for diagnosis of colorectal cancer in older symptomatic patients: two multicentre randomised trials with economic evaluation (SIGGAR1)

7,257). A sensitivity analysis showed that RH+TA is cost-effective than pCCRT when the percentage of patients who require no adjuvant therapy after radical hysterectomy exceeds 30%. Triage strategy was more expensive and more effective, with an incremental cost-effectiveness ratio (ICER) of

Health psychology assessment

39,271 per year of life saved (YLS) compared to RH+TA. Results are relatively sensitive to variation in how the rate of patients who require adjuvant therapy after surgery decrease in MRI-based strategy. cOnclusiOns: RH+TA is cost-effective than pCCRT in Stage IB cervical cancer. Given the current high rates of adjuvant therapy after primary radical surgery in Stage IB cervical cancer, MRI-based strategy has potential to be cost-effective when compared to RH+TA at high test performance and at the lower range of test costs.