Introducing Colorectal Cancer Screening in Romania - Preliminary Results from the Regional Pilot Programs (ROCCAS).

BACKGROUND AND AIMS: Colorectal cancer (CRC) is the third cause of cancer-related death worldwide. Screening programs can reduce CRC mortality rates by up to 60%. In line with the European Union recommendations, Romania started the first four regional pilot screening programs in 2020 (the ROCCAS II projects). This study reports the interim screening performance indicators. METHODS: People aged 50 to 74 years were invited to the screening program. General practitioners (GPs) evaluated CRC risk based on a survey. High-risk or symptomatic individuals were referred directly to colonoscopy. The average risk participants received a fecal immunochemical test (FIT). Positive cases were invited to colonoscopy. Three regions were screened using the OC-SENSOR® (South-Muntenia, Bucharest-Ilfov, South-East) and one region (South-West) used the FOB GOLD®. The data was collected in the ROCCAS screening electronic registry. The following FIT parameters were evaluated: rates of return, invalidity, positivity, and colonoscopy acceptance rate according to age group, gender, region of provenience, and vulnerability status. RESULTS: We included all cases screened between January 1, 2022 and September 30, 2023. In total, 168,958 people received the FIT test within the projects. The global FIT return rate was 90%. Factors associated with a higher return rate were female gender (90.77% vs 88.83%, p<0.0001), vulnerable status (91.23% vs 88.83%; p<0.00001), and rural residence (91.84% vs 88.42%, p<0.00001). The overall positivity rate was 5.75%. It was higher in males (7.64% vs 4.57% in females, p<0.00001) and progressively increased with the age group. The total invalid FIT rate was 5.87%, significantly lower for OC-SENSOR® (2.24%) than for the FOB GOLD® (13.6%). The overall acceptability rate for colonoscopy was 51.3%. CONCLUSIONS: According to our preliminary data, GP's participation in the pilot programs ensured adequate adherence to screening through FIT. The rate for FIT return and positivity were acceptable for both tests, while the invalid rate was much higher in FOB GOLD® compared to the OC-SENSOR®. Moreover, colonoscopy acceptance needs to be improved. Our preliminary analysis revealed the screening performance indicators meet the EU recommendations and fulfill the premises for national-level expansion of the program starting in 2024.

An efficient strategy for evaluating new non-invasive screening tests for colorectal cancer: the guiding principles.

OBJECTIVE: New screening tests for colorectal cancer (CRC) are rapidly emerging. Conducting trials with mortality reduction as the end point supporting their adoption is challenging. We re-examined the principles underlying evaluation of new non-invasive tests in view of technological developments and identification of new biomarkers. DESIGN: A formal consensus approach involving a multidisciplinary expert panel revised eight previously established principles. RESULTS: Twelve newly stated principles emerged. Effectiveness of a new test can be evaluated by comparison with a proven comparator non-invasive test. The faecal immunochemical test is now considered the appropriate comparator, while colonoscopy remains the diagnostic standard. For a new test to be able to meet differing screening goals and regulatory requirements, flexibility to adjust its positivity threshold is desirable. A rigorous and efficient four-phased approach is proposed, commencing with small studies assessing the test's ability to discriminate between CRC and non-cancer states (phase I), followed by prospective estimation of accuracy across the continuum of neoplastic lesions in neoplasia-enriched populations (phase II). If these show promise, a provisional test positivity threshold is set before evaluation in typical screening populations. Phase III prospective studies determine single round intention-to-screen programme outcomes and confirm the test positivity threshold. Phase IV studies involve evaluation over repeated screening rounds with monitoring for missed lesions. Phases III and IV findings will provide the real-world data required to model test impact on CRC mortality and incidence. CONCLUSION: New non-invasive tests can be efficiently evaluated by a rigorous phased comparative approach, generating data from unbiased populations that inform predictions of their health impact.

Metachronous neoplasms in patients with laterally spreading tumours during surveillance.

BACKGROUND: Laterally spreading tumours represent a major challenge for endoscopic detection and resection. OBJECTIVE: To examine synchronous and metachronous neoplasms in patients with laterally spreading tumours. METHODS: We prospectively collected colonoscopy and histopathology data from patients who underwent colonoscopy in our centre at up to 6 years' follow-up. Post-resection surveillance outcomes between laterally spreading tumours, flat colorectal neoplasms 10 mm or greater, and large polypoid colorectal neoplasms, polypoid colorectal neoplasms 10 mm or greater, were compared. RESULTS: Between 2008 and 2012, 8120 patients underwent colonoscopy for symptoms (84.6%), screening (6.7%) or surveillance (8.7%). At baseline, 151 patients had adenomatous laterally spreading tumours and 566 patients had adenomatous large polypoid colorectal neoplasms. Laterally spreading tumour patients had more synchronous colorectal neoplasms than large polypoid colorectal neoplasm patients (mean 3.34 vs. 2.34, p < 0.001). Laterally spreading tumour patients significantly more often developed metachronous colorectal neoplasms (71.6% vs. 54.2%, p = 0.0498) and colorectal neoplasms with high grade dysplasia/submucosal invasion than large polypoid colorectal neoplasm patients (36.4% vs. 15.8%, p < 0.001). After correction for age and gender, laterally spreading tumour patients were more likely than large polypoid colorectal neoplasm patients to develop a colorectal neoplasm with high grade dysplasia or submucosal invasion (hazard ratio 2.9, 95% confidence interval 1.8-4.6). The risk of metachronous colorectal cancer was not significantly different in laterally spreading tumours compared to large polypoid colorectal neoplasm patients. CONCLUSION: Patients with laterally spreading tumours developed more metachronous colorectal neoplasms with high grade dysplasia/submucosal invasion than large polypoid colorectal neoplasm patients. Based on these findings endoscopic treatment and surveillance recommendations for patients with laterally spreading tumours should be optimised.

Optical diagnosis of diminutive polyps in the Dutch Bowel Cancer Screening Program: Are we ready to start?

Background and study aims Implementation of optical diagnosis of diminutive polyps may potentially increase the efficacy and cost-effectiveness of colonoscopies. To adopt such strategy in clinical practice, the Preservation and Incorporation of Valuable endoscopic Innovations (PIVI) thresholds provide the basis to be met: ≥ 90 % negative predictive value (NPV) for diagnosis of adenomatous histology and ≥ 90 % agreement on surveillance intervals. We evaluated this within the Dutch Bowel Cancer Screening Program (BCSP). Patients and methods Endoscopic and histological data were collected from participants of the national bowel cancer screening program with an unfavorable fecal immunochemical test referred for colonoscopy between February 2014 and August 2015 at four endoscopy centers. The "resect and discard" scenario was studied, resecting diminutive polyps without histological evaluation. Agreement between optical diagnosis and histological diagnosis was measured for surveillance intervals according to Dutch, European and American post-polypectomy surveillance guideline. Results Fifteen certified endoscopists participated in this study and included 3028 diminutive polyps. In 2,330 patients both optical and histological diagnosis were available. Optical diagnosis of diminutive polyps showed NPV of 84 % (95 % CI 80-87) for adenomatous histology in the rectosigmoid. Applying the 'resect and discard' strategy resulted in 90.6 %, 91.2 %, 90.9 % agreement on surveillance intervals for the Dutch, European and American guideline respectively. Conclusion Our data representing current clinical practice in the Dutch BCSP practice on optical diagnosis of diminutive polyps showed that accuracy of predicting histology remains challenging, and risk of incorrect optical diagnosis is still significant. Therefore, it is too early to safely implement these strategies.

G-EYE colonoscopy is superior to standard colonoscopy for increasing adenoma detection rate: an international randomized controlled trial (with videos).

BACKGROUND AND AIMS: Colorectal cancer (CRC) is largely preventable with routine screening and surveillance colonoscopy; however, interval cancers arising from precancerous lesions missed by standard colonoscopy still occur. An increased adenoma detection rate (ADR) has been found to be inversely associated with interval cancers. The G-EYE device includes a reusable balloon integrated at the distal tip of a standard colonoscope, which flattens haustral folds, centralizes the colonoscope's optics, and reduces bowel slippage. The insufflated balloon also aims to enhance visualization of the colon during withdrawal, thereby increasing the ADR. METHODS: In this randomized, controlled, international, multicenter study (11 centers), patients (aged ≥50 years) referred to colonoscopy for screening, surveillance, or changes in bowel habits were randomized to undergo either balloon-assisted colonoscopy by using an insufflated balloon during withdrawal or standard high-definition colonoscopy. The primary endpoint was the ADR. RESULTS: One thousand patients were enrolled between May 2014 and September 2016 to undergo colonoscopy by experienced endoscopists; 803 were finally analyzed (standard colonoscopy n = 396; balloon-assisted colonoscopy n = 407). Baseline parameters were similar in both groups. Balloon-assisted colonoscopy provided a 48.0% ADR compared with 37.5% in the standard colonoscopy group (28% increase; P = .0027). Additionally, balloon-assisted colonoscopy provided for a significant increase in detection of advanced (P = .0033) flat adenomas (P < .0001) and sessile serrated adenomas/polyps (P = .0026). CONCLUSION: Balloon-assisted colonoscopy yielded a higher ADR and increased the detection of advanced, flat, and sessile serrated adenomas/polyps when compared with standard colonoscopy. Improved detection by the G-EYE device could impact the quality of CRC screening by reducing miss rates and consequently reducing interval cancer incidence. (Clinical trial registration number: NCT01917513.).

Incidence and Classification of Postcolonoscopy Colorectal Cancers in Inflammatory Bowel Disease: A Dutch Population-Based Cohort Study.

BACKGROUND AND AIMS: Patients with inflammatory bowel disease [IBD] colitis are at increased risk for colorectal cancer [CRC]. We examined the proportion and most likely aetiology of potentially preventable postcolonoscopy CRCs [PCCRCs] in a population-based cohort. Furthermore, adherence to IBD surveillance guidelines was evaluated in both PCCRCs and the remainder of prevalent CRCs. METHODS: All IBD patients diagnosed from 1991 to 2011 in the South Limburg region of The Netherlands [i.e. IBDSL cohort] were included. CRC cases were cross-checked with the Dutch pathology database and cancer registry. PCCRCs were defined as cancers diagnosed within 6-60 months after a colonoscopy and were classified as attributable to 'inappropriate surveillance interval', 'inadequate bowel examination', 'incomplete resection', 'missed lesion' or 'newly developed cancer'. RESULTS: Twenty CRC cases were identified during 25,931 patient years of follow-up in 2,801 patients. The proportion of PCCRCs was 45.0%. Of these, 55.6% could be considered a 'missed lesion', while other possible aetiologies occurred only once. Considering both PCCRCs [n=9] and prevalent CRCs [n=11], ten were detected after publication of the surveillance guideline, but only three patients were enrolled. Moreover, 6 CRCs [30.0%] were detected before the recommended start of surveillance. CONCLUSIONS: In the IBDSL cohort, 45.0% of all CRCs were considered to be PCCRCs, mainly classified as missed lesions. Additionally, a large proportion of CRCs in our cohort were observed before a surveillance endoscopy was performed. Therefore, stringent adherence to IBD surveillance guidelines, improving endoscopy techniques and adjusting the surveillance program may lead to a decrease in CRC incidence.

Endoscopic subtypes of colorectal laterally spreading tumors (LSTs) and the risk of submucosal invasion: a meta-analysis.

BACKGROUND AND STUDY AIMS: Many studies have reported on laterally spreading tumors (LSTs), but systematic reviews of the data to determine their risk of containing submucosal invasion (SMI) are lacking. We systematically screened and analyzed the available literature to provide a more solid basis for evidence-based treatment. METHODS: We conducted a systematic search in PubMed, Embase, the Cochrane Library, and Scopus for published articles until July 2017. We estimated pooled prevalence or odds ratios (ORs) with 95 % confidence intervals (CIs), using random-effects models. We classified endoscopic subtypes into granular LST, which comprises the homogeneous and nodular mixed subtypes, and non-granular LST, which comprises the flat elevated and pseudodepressed subtypes. RESULTS: We identified 2949 studies, of which 48 were included. Overall, 8.5 % (95 %CI 6.5 % - 10.5 %) of LSTs contained SMI. The risk of SMI differed among the LST subtypes: 31.6 % in non-granular pseudodepressed LSTs (95 %CI 19.8 % - 43.4 %), 10.5 % in granular nodular mixed LSTs (95 %CI 5.9 % - 15.1 %), 4.9 % in non-granular flat elevated LSTs (95 %CI 2.1 % - 7.8 %), and 0.5 % in granular homogenous LSTs (95 %CI 0.1 % - 1.0 %). SMI was more common in distally rather than in proximally located LSTs (OR 2.50, 95 %CI 1.24 - 5.02). The proportion of SMI increased with lesion size (10 - 19 mm, 4.6 %; 20 - 29 mm, 9.2 %; ≥ 30 mm, 16.5 %). The pooled prevalence of patients with one or more LSTs in the general colonoscopy population was 0.8 % (95 %CI 0.6 % - 1.1 %). CONCLUSION: The majority of LSTs are non-invasive at the time of colonoscopic detection and can be treated with (piecemeal) endoscopic mucosal resection. Pretreatment diagnosis of endoscopic subtype, specifying areas of concern (nodule or depression), determines those LSTs at highest risk of containing SMI, where en bloc resection is the preferred therapy.

Polyp morphology: an interobserver evaluation for the Paris classification among international experts.

OBJECTIVES: The Paris classification is an international classification system for describing polyp morphology. Thus far, the validity and reproducibility of this classification have not been assessed. We aimed to determine the interobserver agreement for the Paris classification among seven Western expert endoscopists. METHODS: A total of 85 short endoscopic video clips depicting polyps were created and assessed by seven expert endoscopists according to the Paris classification. After a digital training module, the same 85 polyps were assessed again. We calculated the interobserver agreement with a Fleiss kappa and as the proportion of pairwise agreement. RESULTS: The interobserver agreement of the Paris classification among seven experts was moderate with a Fleiss kappa of 0.42 and a mean pairwise agreement of 67%. The proportion of lesions assessed as "flat" by the experts ranged between 13 and 40% (P<0.001). After the digital training, the interobserver agreement did not change (kappa 0.38, pairwise agreement 60%). CONCLUSIONS: Our study is the first to validate the Paris classification for polyp morphology. We demonstrated only a moderate interobserver agreement among international Western experts for this classification system. Our data suggest that, in its current version, the use of this classification system in daily practice is questionable and it is unsuitable for comparative endoscopic research. We therefore suggest introduction of a simplification of the classification system.