Introduction

Advancements in colonoscope technology have been identified as one of the factors that can affect the quality of colonoscopy, positively affecting adenoma detection rate (ADR). In recent years, new-generation endoscopic system (video system center and colonoscope) and 4K monitors have been released. These instruments provide endoscopists with higher resolution and lower noise images than previous-generation endoscopic instruments. However, it is unclear whether these new-generation endoscopic instruments can enhance the adenoma detection ability.

Aims & Methods

We aimed to clarify the colorectal adenoma detection ability of new-generation endoscopic instruments by comparing them with previous-generation endoscopic instruments. This study was a retrospective single-center study in patients undergoing screening colonoscopy or surveillance colonoscopy after endoscopic resection or surgical resection for colorectal neoplasm. The X1 group was the group of patients who underwent colonoscopy using new-generation endoscopic instruments (video system center: EVIS X1 CV1500, colonoscope: CF-XZ1200I/CF-EZ1500DI, monitor: 4K) between April 2022 and March 2023. The ELITE group was the group of patients who underwent colonoscopy using previous-generation endoscopic instruments (video system center: EVIS LUCERA ELITE CV290, colonoscope: PCF-H290ZI/CF-HQ290Z, monitor: Full HD) between April 2019 and March 2020. We conducted an analysis for propensity score matched patients using known factors (patient age, sex, purpose of colonoscopy, observation mode, and endoscopists’ expertise) that may have affected the ADR. The patients who were familial adenomatous polyposis, lynch syndrome, or inadequate bowel preparation (Aronchick scale: over 3 score) were excluded. The primary outcome was the ADR. The secondary outcomes were the mean number of adenomas detected per procedure (MAP) and flat polyp detection rate (FDR). We also performed a subgroup analysis comparing ADR, MAP, and FDR by observation mode between white light imaging (WLI) and narrow band imaging (NBI).

Results

480 patients in the X1 group and 1560 patients in the ELITE group were enrolled in this study. After propensity score-matching, 960 patients were finally included in the analysis (480 patients in each group). The patient characteristics were well balanced after propensity score matching between each group. The ADR in the X1 group was significantly higher than that in the ELITE group (55.0% vs 49.0% [McNemar test p=0.049]). The MAP and FDR in the X1 group were also significantly higher than that in the ELITE group (MAP(±SD), 1.52±2.25 vs 1.13±1.77, [Wilcoxon signed rank sum test p=0.004]; FDR, 50.0% vs 39.4%, [p<0.001]). In the subgroup analysis by observation mode, in NBI mode, the MAP in the X1 group was significantly higher than that in the ELITE group (1.52±2.00 vs 1.20±1.83, [Wilcoxon rank sum test p=0.047]). In WLI mode, the FDR in the X1 group was significantly higher than that in the ELITE group (46.3% vs 30.2%, [Fisher’s exact test p=0.0012]).

Conclusion

Our study indicated that the use of new-generation endoscopic instruments improved the colorectal adenoma detection ability.

Introduction

Improving the adenoma detection rate (ADR) can contribute to reducing the incidence and mortality of post-colonoscopy colorectal cancer (PCCRC). Texture and color enhancement imaging (TXI) enhances subtle tissue textures, selectively brightens dark areas, and emphasizes the differences between red and white colors^1,2. Several studies have investigated the visibility and color differences of TXI in vitro and reported its superiority over WLI^3-7. However, A few studies have evaluated the ADR of colonoscopy with TXI, which is a novel image-enhancing technology. This study aims to compare the detection of colorectal polyps using TXI to that using white light imaging (WLI).

Aims & Methods

This study was conducted retrospectively in a single center using propensity-matched scoring based on the patients’ baseline characteristics, such as age, sex, indication, bowel preparation, endoscopist, colonoscope type, and withdrawal time. This study compared the effectiveness of WLI and TXI in patients who underwent chromocolonoscopy with indigo carmine spraying. The study determined the differences in the adenoma, including high-risk adenoma, and sessile serrated lesion (SSL) detection rates and the mean number of detected adenomas and SSLs per colonoscopy between the TXI and WLI groups. High-risk adenomas were defined as three or more adenomas, an adenoma ≥10 mm, an adenoma with a villous component, and an adenoma with high-grade dysplasia. The Wald test with logistic regression was used to analyze the P values.

Results

After propensity score matching, 1970 patients were enrolled into each imaging modality group. The mean patient age was 57.2 ± 12.5 years, and 44.5% of the cohort were men. The ADR was higher in the TXI group than in the WLI group (55.0% vs. 49.4%, odds ratio: 1.25). High-risk ADR were more common in the TXI group than in the WLI group (17.6% vs. 12.8%; OR: 1.45). The mean number of adenomas per colonoscopy (APC) was higher in the TXI group than in the WLI group (1.187 vs. 0.943, OR: 1.12). APC with a 0-II morphology according to the Paris classification (1.093 vs. 0.848, OR: 1.14) and APC of <6 mm (0.992 vs. 0.757, OR: 1.16) were higher in the TXI group than in the WLI group. The adenoma plus SSL detection rate (ASDR) was higher in the TXI group than in the WLI group (58.8% vs. 53.2%, OR: 1.25). The mean number of adenomas plus SSLs per colonoscopy (ASPC) was greater in the TXI group than in the WLI group (1.287 vs. 1.025, OR: 1.13, Table).

Conclusion

A randomized controlled trial⁸ and a cross-over study⁹ previously showed that the ADR of TXI was higher than that of WLI. In this study, we found that the ADR, high-risk ADR, APC, ASDR, and ASPC of TXI were higher than those of WLI after propensity-score matching of patients who underwent chromoendoscopy. TXI may help prevent PCCRC.

References

1 Sato T. TXI: Texture and Color Enhancement Imaging for Endoscopic Image Enhancement. J Healthc Eng 2021; 2021.
2 Tani Y, et al. Gastrointestinal: Texture and color enhancement imaging is useful for detection of small gastric adenocarcinoma of fundic-gland type. J Gastroenterol Hepatol 2024.
3 Nishizawa T, et al. TXI (Texture and Color Enhancement Imaging) for Serrated Colorectal Lesions. J Clin Med 2021.
4 Toyoshima O, et al. Texture and color enhancement imaging in magnifying endoscopic evaluation of colorectal adenomas. World J Gastrointest Endosc 2022.
5 Tamai N, et al. Visibility evaluation of colorectal lesion using texture and color enhancement imaging with video. DEN Open 2022.
6 Yoshida N, et al. Analysis of Texture and Color Enhancement Imaging for Improving the Visibility of Non-polypoid Colorectal Lesions. Dig Dis Sci 2022.
7 Hiramatsu T, et al. Improved visibility of colorectal tumor by texture and color enhancement imaging with indigo carmine. World J Gastrointest Endosc 2023.
8. Antonelli G, et al. Texture and color enhancement imaging versus high definition white-light endoscopy for detection of colorectal neoplasia: a randomized trial. Endoscopy 2023.
9. Sakamoto T, et al. Detection of colorectal adenomas with texture and color enhancement imaging: Multicenter observational study. Dig Endosc 2023.

Disclosure

​Nothing

Introduction

Adenomas per Colonoscopy (APC) might serve as an adjuvant quality metric to the Adenoma Detection Rate (ADR). This indicator is calculated by dividing the total number of detected adenomas by the number of colonoscopies performed. It motivates the operator to maximize adenoma identification and removal during screening procedures and allows a more comprehensive assessment of the colonoscopy's quality.

Aims & Methods

The aims of this study were to assess the association between the ADR and the APC metrics in colorectal cancer screening and to explore factors influenciating each of these indicators. This retrospective, single-center study analyzed total screening colonoscopies conducted on 50 years old or more patients, over a period of 18 months (from April 2022 to September 2023) and their corresponding histological reports. Colonoscopies with at least one colonic segment with less than 2 points on the Boston Bowel Preparation Scale (BBPs) were excluded. Statistical analysis was performed using SPSS v29.0.

Results

502 total colonoscopies were included. ADR was 41.7% and APC was 76.5%. The number of adenomas per colonoscopy ranged from 0 to 11 adenomas. There was a positive statistically significant association between the ADR and the APC (β=0.6, p<0.001). No statistically significant difference was found in the average age between patients with and without adenomas (p>0.05), nor a correlation between age and the number of APC (p>0.05). Men were 2.1 times more likely to have at least one adenoma (p<0.05) and the average number of adenomas per colonoscopy was statistically significant higher in men (p<0.05). The BBPS score was not associated with the detection of at least one adenoma or to the total number of adenomas per colonoscopy (p>0.05). The average withdrawal time was higher in patients with adenomas (p<0.05), and there was a positive, statistically significant, moderate correlation between withdrawal time and the number of APC (r=0.5; p<0.001). No association was found between the colonoscopy schedule, endoscopist fatigue or experience and the presence of at least one adenoma (p>0.05). The average number of adenomas per colonoscopy was also not statistically significantly different among the previously mentioned groups (p>0.05).

Conclusion

Our study confirmed a significant association between the ADR and the APC, encouraging the use of APC as a complementary metric in colorectal cancer screening. Influencing factors were similar between the two indicators. While gender and withdrawal time significantly influenced adenoma detection and the number of adenomas detected per colonoscopy, with men and longer procedures showing higher ADR and APC rates, other factors such as age, bowel preparation quality, and procedural variables showed no significant impact.

Introduction

Colorectal cancer (CRC) can be divided into screen-detected and non-screen-detected CRC. Furthermore, based on the interval between CRC detection and a previous screening or examination, CRC can be classified into several groups, including interval cancer and post-colonoscopy CRC. The proportion and characteristics of each CRC need to be clarified to understand the usefulness and limitations of CRC screening; however, they have not been fully elucidated. Particularly, little data is available on interval cancer under the annual fecal immunochemical test (FIT) screening.

Aims & Methods

We aimed to examine the proportions and characteristics of CRC with different detection histories by conducting a multicenter prospective study in Japan (“C-DETECT study”). Consecutive adult patients with CRC were prospectively enrolled in four hub hospitals of cancer treatment. CRC detection methods and intervals from previous examinations were assessed using a questionnaire. Since the population-based CRC screening using an annual FIT is performed in Japan, FIT-interval cancer was defined as CRC detected within 1 year following a previous negative FIT. Three-year post-colonoscopy CRC (PCCRC-3yr), which was defined as CRC detected within 3 years after the previous colonoscopy with negative CRC, was also investigated. Differences in the lesion and patient characteristics were compared for patients with the following CRC using the chi-squared test: i) screen-detected and non-screen-detected CRC; ii) (a) FIT-interval cancer, (b) PCCRC-3yr, (c) CRC detected within 1 year after a positive FIT with noncompliance to colonoscopy, and (d) CRC other than (a), (b), and (c).

Results

Of 1,241 CRC patients (1064 with invasive and 177 with intramucosal CRC), 475 (38.3%) had screen-detected and 766 (61.7%) had non-screen-detected CRCs. Non-screen detected CRCs showed significantly higher proportions of presence of ≥T2 invasion, metastasis, worse histology (poorly differentiated adenocarcinoma, signet-ring cell, or mucinous carcinoma) and left-sided CRCs than screen-detected CRC (82.1% vs 52.8% (P<0.01); 52.0% vs 26.7% (P<0.01); 18.7% vs 11.4% (P<0.01); 71.1% vs 61.7% (P<0.01), respectively). FIT-interval cancer (a), PCCRC-3yr (b), and CRC detected within 1 year after a positive FIT with noncompliance to colonoscopy (c) accounted for 4.5%, 7.0%, and 3.9% of all CRCs, respectively, and for 3.9%, 5.4%, and 4.3% of invasive CRCs, respectively. The comparison among these three types (a, b, c) and the other (d) demonstrated a significant difference in the proportions of ≥T2 invasion ((a) 58.9%, (b) 44.8%, (c) 87.5%, and (d) 73.0%, respectively (P<0.01)), metastasis ((a) 33.9%, (b) 21.8%, (c) 54.2%, and (d) 43.9%, respectively (P<0.01)), right-sided CRC ((a) 42.9%, (b) 40.2%, (c) 18.8%, and (d) 28.6%, respectively (P<0.01)), and female patients ((a) 53.6%, (b) 49.4%, (c) 27.1%, and (d) 41.6% respectively (P=0.02)).

Conclusion

Non-screen-detected CRC accounted for a large proportion of patients and demonstrated advanced characteristics in terms of invasion depth and metastasis, as well as CRC detected shortly after a positive FIT with no colonoscopy. These findings emphasize the importance of screening and colonoscopy compliance following a positive FIT. Notably, FIT-interval cancer and PCCRC-3yr existed in non-negligible proportions even under the annual FIT screening system and were characterized by higher proportions of a right-sided location and female. This novel finding suggests that these two types of CRCs may have different biological features from the others.

Introduction

Artificial intelligence has recently been developed to improve polyp detection. The aim of this study was to evaluate the impact of real-time computer-aided detection (CADe) systems on the adenoma detection rate (ADR) in routine colonoscopy.

Aims & Methods

This monocentric randomized trial compared standard colonoscopy to CADe-assisted colonoscopy (GI Genius^TM, Medtronic). According to statistical calculations, 20 endoscopists from the Clinique Paris-Bercy (Charenton-le-Pont, France) had to include approximately 2,100 patients with a 1:1 randomization. The operator was not blinded to the study arm assigned to the patient. All consecutive patients aged ≥ 18 years who were scheduled for colonoscopy in our unit were screened during colonoscopy planning. The main criterion was ADR. The COLO-GENIUS trial is complete and registered with ClinicalTrials.gov, NCT04440865.

Results

A total of 2,104 patients were included from May 1, 2021 to May 1, 2022. 2,015 patients (979 men/1,036 women) were randomized (1,012 for standard colonoscopy vs. 1,003 for CADe-assisted colonoscopy). Both groups were comparable.
ADR increased from 33.7% in the standard group to 37.5% in the CADe group (estimated mean absolute difference: 4.1% [95% CI: 0.0%;8.1%], P=0.051), while the polyp detection rate (PDR) increased from 41.0% to 45.0% (estimated mean absolute difference; 4.3 % [95% CI: 0.0%;8.5%], P=0.048) and the mean number of adenomas per colonoscopy (APC) increased from 0.71±1.30 to 0.89±1.49 (0.17 [95% CI: 0.10;0.25], P<0.001). Difference was not significant for Advanced ADR which increased from 7.6% to 9.3% (estimated mean absolute difference:1.7% [95% CI: -0.8%;4.1%], P=0.18).
One bleeding event without deglobulization occurred (in the CADe group) after a large (> 2cm) polyp resection, resolved after a hemostasis clip was placed during a second colonoscopy.

Percentages and estimated absolute differences, for the primary outcome (ADR) and the secondary outcomes (PDR, ANDR, PSPDR and APC)

Conclusion

This large randomized study performed in a non-academic center supports the benefits of CADe (GI Genius^TM, Medtronic) regarding ADR and APC, thus suggesting the systematic use of CADe in routine colonoscopy. However, the impact of CADe on ADR is low, especially among high detectors.

Disclosure

Competing interests in relation to the study: None declared.
Other competing interest:
David Karsenti, MD: Consultant for OLYMPUS; Support for attending meetings from ALFASIGMA and FUJIFILM
Franck Venezia, MD: Honoraria for lectures, presentations, speakers for ABBVIE, TAKEDA, AMGEN and JANSSEN-CILAG; Support for attending meetings from ABBVIE; Board for JANSSEN-CILAG and BIOGEN
Maryan Cavicchi, MD-PhD: Consultant for JANSSEN-CILAG, ABBVIE and MSD; Honoraria for lectures, presentations, speakers for MSD France, AMGEN, TAKEDA, PFIZER, MYLAN and TILLOTS; Support for attending meetings from FERRING, TAKEDA and MSD; Board for JANSSEN-CILAG, ABBVIE; Receipt of equipment, materials from CELTRION and BIOSYNEX
The other authors have declared no conflict of interest