Diagnostic performance of magnifying endoscopy with narrow-band imaging in differentiating neoplastic colorectal polyps from non-neoplastic colorectal polyps: a meta-analysis

Impact of an artificial intelligence-aided endoscopic diagnosis system on improving endoscopy quality for trainees in colonoscopy: Prospective, randomized, multicenter study

OBJECTIVE

This study was performed to evaluate whether the use of CAD EYE (Fujifilm, Tokyo, Japan) for colonoscopy improves colonoscopy quality in gastroenterology trainees.

METHODS

The patients in this multicenter randomized controlled trial were divided into Group A (observation using CAD EYE) and Group B (standard observation). Six trainees performed colonoscopies using a back-to-back method in pairs with gastroenterology experts. The primary end-point was the trainees' adenoma detection rate (ADR), and the secondary end-points were the trainees' adenoma miss rate (AMR) and Assessment of Competency in Endoscopy (ACE) tool scores. Each trainee's learning curve was evaluated using a cumulative sum (CUSUM) control chart.

RESULTS

We analyzed data for 231 patients (Group A, n = 113; Group B, n = 118). The ADR was not significantly different between the two groups. Group A had a significantly lower AMR (25.6% vs. 38.6%, P = 0.033) and number of missed adenomas per patient (0.5 vs. 0.9, P = 0.004) than Group B. Group A also had significantly higher ACE tool scores for pathology identification (2.26 vs. 2.07, P = 0.030) and interpretation and identification of pathology location (2.18 vs. 2.00, P = 0.038). For the CUSUM learning curve, Group A showed a trend toward a lower number of cases of missed multiple adenomas by the six trainees.

CONCLUSION

CAD EYE did not improve ADR but decreased the AMR and improved the ability to accurately locate and identify colorectal adenomas. CAD EYE can be assumed to be beneficial for improving colonoscopy quality in gastroenterology trainees.

TRIAL REGISTRATION

University Hospital Medical Information Network Clinical Trials Registry (UMIN000044031).

The Utility of Narrow-Band Imaging International Colorectal Endoscopic Classification in Predicting the Histologies of Diminutive Colorectal Polyps Using I-Scan Optical Enhancement: A Prospective Study

(1) Background: This study aimed to evaluate the accuracy of predicting the histology of diminutive colonic polyps (DCPs) (≤5 mm) using i-scan optical enhancement (OE) based on the narrow-band imaging international colorectal endoscopic (NICE) classification. The study compared the diagnostic accuracy between experts who were already familiar with the NICE classification and trainees who were not, both before and after receiving brief training on the NICE classification. (2) Method: This prospective, single-center clinical trial was conducted at the Dong-A University Hospital from March 2020 to August 2020 and involved two groups of participants. The first group comprised two experienced endoscopists who were proficient in using i-scan OE and had received formal training in optical diagnosis and dye-less chromoendoscopy (DLC) techniques. The second group consisted of three endoscopists in the process of training in internal medicine at the Dong-A University Hospital. Each endoscopist examined the polyps and evaluated them using the NICE classification through i-scan OE. The results were not among the participants. Trained endoscopists were divided into pre- and post-training groups. (3) Results: During the study, a total of 259 DCPs were assessed using i-scan OE by the two expert endoscopists. They made real-time histological predictions according to the NICE classification criteria. For the trainee group, before training, the area under the receiver operating characteristic curves (AUROCs) for predicting histopathological results using i-scan OE were 0.791, 0.775, and 0.818. However, after receiving training, the AUROCs improved to 0.935, 0.949, and 0.963, which were not significantly different from the results achieved by the expert endoscopists. (4) Conclusions: This study highlights the potential of i-scan OE, along with the NICE classification, in predicting the histopathological results of DCPs during colonoscopy. In addition, this study suggests that even an endoscopist without experience in DLC can effectively use i-scan OE to improve diagnostic performance with only brief training.

Efficacy of image-enhanced endoscopy for colorectal adenoma detection: A multicenter, randomized trial

BACKGROUND

Improved adenoma detection at colonoscopy has decreased the risk of developing colorectal cancer. However, whether image-enhanced endoscopy (IEE) further improves the adenoma detection rate (ADR) is controversial.

AIM

To compare IEE with white-light imaging (WLI) endoscopy for the detection and identification of colorectal adenoma.

METHODS

This was a multicenter, randomized, controlled trial. Participants were enrolled between September 2019 to April 2021 from 4 hospital in China. Patients were randomly assigned to an IEE group with WLI on entry and IEE on withdrawal (n = 2113) or a WLI group with WLI on both entry and withdrawal (n = 2098). The primary outcome was the ADR. The secondary endpoints were the polyp detection rate (PDR), adenomas per colonoscopy, adenomas per positive colonoscopy, and factors related to adenoma detection.

RESULTS

A total of 4211 patients (966 adenomas) were included in the analysis (mean age, 56.7 years, 47.1% male). There were 2113 patients (508 adenomas) in the IEE group and 2098 patients (458 adenomas) in the WLI group. The ADR in two group were not significantly different [24.0% vs 21.8%, 1.10, 95% confidence interval (CI): 0.99-1.23, P = 0.09]. The PDR was higher with IEE group (41.7%) than with WLI group (36.1%, 1.16, 95%CI: 1.07-1.25, P = 0.01). Differences in mean withdrawal time (7.90 ± 3.42 min vs 7.85 ± 3.47 min, P = 0.30) and adenomas per colonoscopy (0.33 ± 0.68 vs 0.28 ± 0.62, P = 0.06) were not significant. Subgroup analysis found that with narrow-band imaging (NBI), between-group differences in the ADR, were not significant (23.7% vs 21.8%, 1.09, 95%CI: 0.97-1.22, P = 0.15), but were greater with linked color imaging (30.9% vs 21.8%, 1.42, 95%CI: 1.04-1.93, P = 0.04). the second-generation NBI (2G-NBI) had an advantage of ADR than both WLI and the first-generation NBI (27.0% vs 21.8%, P = 0.01; 27.0% vs 21.2.0%, P = 0.01).

CONCLUSION

This prospective study confirmed that, among Chinese, IEE didn’t increase the ADR compared with WLI, but 2G-NBI increase the ADR.

Systemic treatment for metastatic colorectal cancer

Significant progress has been achieved in the treatment of metastatic colorectal cancer (mCRC) patients during the last 20 years. There are currently numerous treatments available for the first-line treatment of mCRC. Sophisticated molecular technologies have been developed to reveal novel prognostic and predictive biomarkers for CRC. The development of next-generation sequencing and whole-exome sequencing, which are strong new tools for the discovery of predictive molecular biomarkers to facilitate the delivery of customized treatment, has resulted in tremendous breakthroughs in DNA sequencing technology in recent years. The appropriate adjuvant treatments for mCRC patients are determined by the tumor stage, presence of high-risk pathologic characteristics, microsatellite instability status, patient age, and performance status. Chemotherapy, targeted therapy, and immunotherapy are the main systemic treatments for patients with mCRC. Despite the fact that these novel treatment choices have increased overall survival for mCRC, survival remains optimal for individuals with non-metastatic disease. The molecular technologies currently being used to support our ability to practice personalized medicine; the practical aspects of applying molecular biomarkers to regular clinical practice; and the evolution of chemotherapy, targeted therapy, and immunotherapy strategies for the treatment of mCRC in the front-line setting are all reviewed here.

Systemic treatment for metastatic colorectal cancer

Significant progress has been achieved in the treatment of metastatic colorectal cancer (mCRC) patients during the last 20 years. There are currently numerous treatments available for the first-line treatment of mCRC. Sophisticated molecular technologies have been developed to reveal novel prognostic and predictive biomarkers for CRC. The development of next-generation sequencing and whole-exome sequencing, which are strong new tools for the discovery of predictive molecular biomarkers to facilitate the delivery of customized treatment, has resulted in tremendous breakthroughs in DNA sequencing technology in recent years. The appropriate adjuvant treatments for mCRC patients are determined by the tumor stage, presence of high-risk pathologic characteristics, microsatellite instability status, patient age, and performance status. Chemotherapy, targeted therapy, and immunotherapy are the main systemic treatments for patients with mCRC. Despite the fact that these novel treatment choices have increased overall survival for mCRC, survival remains optimal for individuals with non-metastatic disease. The molecular technologies currently being used to support our ability to practice personalized medicine; the practical aspects of applying molecular biomarkers to regular clinical practice; and the evolution of chemotherapy, targeted therapy, and immunotherapy strategies for the treatment of mCRC in the front-line setting are all reviewed here.

Linked color imaging improves visibility of colorectal serrated lesion by high color contrast to surrounding mucosa

OBJECTIVES

This study aimed to objectively evaluate the efficacy of linked color imaging (LCI) in diagnosing colorectal serrated lesions by utilizing visibility scores and color differences.

METHODS

We examined 89 serrated lesions, including 36 hyperplastic polyps (HPs), 47 sessile serrated lesions (SSLs), and six traditional serrated adenomas (TSAs). Visibility changes were scored by six endoscopists as follows: 4, excellent; 3, good; 2, fair; and 1, poor. Furthermore, images obtained by white-light imaging (WLI) or LCI were assessed using the CIELAB color space in the lesion and adjacent mucosa. We calculated the mean color values (L*, a*, and b*) measured at five regions of interest of the sample lesion and surrounding mucosa and derived the color difference (ΔE*).

RESULTS

The visibility scores of both HPs and SSLs in LCI were significantly higher than that in WLI (HPs, 3.67/2.89, P < 0.001; SSLs, 3.07/2.36, P < 0.001). Furthermore, SSLs showed a significantly higher L* value and significantly lower a* and b* values in LCI than the adjacent mucosae (L*, 61.76/58.23, P = 0.016; a*, 14.91/17.58, P = 0.019; b*, 20.42/24.21, P = 0.007), while WLI produced no significant difference in any color value. A similar trend was apparent in HPs. In all serrated groups, LCI revealed significantly greater ΔE* values between the lesion and adjacent mucosa than WLI (HPs, 11.54/6.12; SSLs, 13.43/7.67; TSAs, 35.00/22.48).

CONCLUSION

Linked color imaging showed higher color contrast between serrated lesions and the surrounding mucosae compared with WLI, indicating improved visibility of colorectal serrated lesion using LCI.

Performance of Computer-Aided Detection and Diagnosis of Colorectal Polyps Compares to That of Experienced Endoscopists

BACKGROUND

Differential diagnosis of neoplasms and non-neoplasms is crucial in ensuring appropriate and proper medical management for patients undergoing colonoscopy. Diagnostic ability can vary, depending on the colonoscopist's experience. To overcome this issue, artificial intelligence (AI) may be effective.

AIMS

To assess the performance of a computer-aided detection (CADe) and a computer-aided diagnosis (CADx) system for the detection and characterization of colorectal polyps by comparing their data with those of experienced endoscopists.

METHODS

This retrospective, still image-based validation study was conducted at three Japanese medical centers. A total of 579 white-light images (WLIs) and 605 linked color images (LCIs) were used for testing the CADe and 308 WLIs and 296 blue laser/light images (BLIs) for testing the CADx. The performances of the CADe and CADx systems were assessed and compared with the correct answers provided by three experienced endoscopists.

RESULTS

CADe in WLI demonstrated a sensitivity of 94.5% (95% confidence interval (CI), 92.0-96.9%) and a specificity of 87.2% (84.5-89.9%). CADe in LCI demonstrated a sensitivity of 96.0% (93.9-98.1%) and a specificity of 85.1% (82.3-87.9%). CADx in WLI demonstrated a sensitivity of 95.5% (92.9-98.1%) and a specificity of 84.4% (73.4-91.5%), resulting in an accuracy of 93.2% (90.4-96.0%). CADx in BLI showed a sensitivity of 96.3% (93.9-98.7%) and a specificity of 88.7% (77.1-95.1%), resulting in an accuracy of 94.9% (92.4-97.4%).

CONCLUSIONS

CADe and CADx demonstrated sufficient diagnostic performance to support the use of an AI system.

Effect of Linked-color Imaging on the Detection of Adenomas in Screening Colonoscopies

OBJECTIVES

Linked-color imaging (LCI) is a new image-enhancement option that emphasizes mucosal surface contrast, facilitating the differentiation between colorectal lesions and normal mucosa. This study aimed to evaluate the potential of LCI to increase the detection of colorectal adenomas in screening colonoscopies.

METHODS

A prospective randomized study was conducted using white-light imaging (WLI), blue-laser imaging (BLI)-bright and LCI. The outcome measures were adenoma detection rate (ADR), mean number of adenomas per patient, and withdrawal time. Lesion characteristics such as size, morphology, location, and histology were also evaluated.

RESULTS

A total of 205 patients were randomized, and 251 adenomas were detected. The overall ADR was 62%. The ADR was 52.9% for WLI, 62.1% for BLI-bright, and 71% for LCI, and was significantly higher in the LCI group than in the WLI group (P=0.04). No significant difference was observed between LCI and BLI-bright (P=0.28) or BLI-bright and WLI (P=0.30). The mean number of adenomas per patient was 1.01, 1.03, and 1.62 for WLI, BLI-bright, and LCI, respectively, with a significant difference (P=0.02). Withdrawal time did not differ among the groups. A total of 71 adenomas were detected by WLI, 68 by BLI-bright, and 112 by LCI. There was no difference in the size and morphology of the adenomas detected, nor in the diagnosis of sessile serrated adenomas/polyps.

CONCLUSION

LCI significantly increased the detection of adenomas in screening colonoscopies.

Linked color imaging versus white light imaging colonoscopy for colorectal adenoma detection: A randomized controlled trial

BACKGROUND AND AIM

The adenoma detection rate is an important indicator of colonoscopy quality and colorectal cancer incidence. We compared the adenoma detection rates between white light imaging (WLI) and linked color imaging (LCI) colonoscopy.

METHODS

Patients undergoing colonoscopy for positive fecal immunochemical tests, follow-up of colon polyps, and abdominal symptoms at three institutions were randomly assigned to the LCI or WLI groups. Mean adenoma number per patient (including based on endoscopists' experience), adenoma detection rate, cecal intubation time, withdrawal time, mean adenoma number per location, and adenoma size were compared.

RESULTS

The LCI and WLI groups comprised 494 and 501 patients, respectively. No significant differences in the cecal intubation rate (LCI vs WLI: 99.5% vs 99.4%), cecal intubation time, and withdrawal time were noted between groups. The mean adenoma number per patient was significantly higher in the LCI group than in the WLI group (1.07 vs 0.88, P = 0.04), particularly in the descending [0.12 (58/494) vs 0.07 (35/501), P = 0.01] and sigmoid colon [0.41 (201/494) vs 0.30 (149/501), P ≤ 0.001]. However, the adenoma detection rate was 47.1% in the LCI group and 46.9% in the WLI group, with no significant difference (P = 0.93). The total number of sessile-type adenomas was significantly higher in the LCI group than in the WLI group (346/494 vs 278/501, P = 0.04). As for polyp size, small polyps (≤ 5 mm) were detected at a significantly higher rate in the LCI group (271/494 vs 336/501, P = 0.04).

CONCLUSION

Linked color imaging is significantly superior to WLI in terms of mean adenoma number per patient.

Value of Magnifying Chromoendoscopy and Magnifying Optical Enhancement Technology in Classifying Colorectal Polyps: A Prospective Controlled Study

Background and Aims

Magnifying chromoendoscopy (ME-CE) through the observation of pit patterns is a productive way to distinguish between neoplastic and nonneoplastic polyps. Magnifying optical enhancement technology (ME-OE) is an emerging virtual chromoendoscopy imaging technology and appeared to be a promising approach. However, this information is currently not available. This study is aimed at comparing the differential diagnostic value of ME-CE and OE for neoplastic and nonneoplastic polyps. Patients and Methods. Consecutive patients undergoing colonoscopy were randomized (1 : 1) into examination by ME-OE or ME-CE. Histopathological findings were utilized as the reference standard. Accuracy, sensitivity, specificity, and positive and negative predictive values of two endoscopy methods were compared using ME-OE (were classified according to the JNET classification) and ME-CE (were classified according to the Kudo pit pattern classification), respectively, and the time to predict the histological polyp type was compared. And the agreements between the pathological and clinical diagnosis by ME-OE or ME-CE were analyzed.

Results

A total of 365 polyps were found in the 220 patients included (ME-OE: 185; ME-CE: 180.202 had nonneoplastic polyps, 163 had neoplastic polyps). The diagnostic accuracy of ME-OE was higher than that of ME-CE (93% vs. 92%, p > 0.05). The average diagnosis time was lower in ME-OE than ME-CE (83 ± 26.4 s vs. 194 ± 17.7 s, p < 0.001). The agreements between the pathological and clinical diagnosis were at least substantial in both groups.

Conclusion

ME-OE was superlative to ME-CE in predicting the histology of polyps. OE devoted classification would possibly similarly enhance the endoscopist performance. The trial is registered with ChiCT2000032075.

[Japan narrow-band imaging Expert Team type 2B colorectal cancer: consistency between endoscopic prediction and pathological diagnosis]

OBJECTIVE

To explore the potential factors that affect the accuracy of endoscopic diagnosis for Japan narrow-band imaging (NBI) Expert Team (JNET) type 2B colorectal lesions.

OBJECTIVE

The clinical data were collected from 261 patients with JNET type 2B colorectal lesions diagnosed in Nanfang Hospital between July, 2018 and July, 2021. We analyzed the macroscopic type, size, location or pit pattern classification of the lesions for their potential influence of the diagnostic accuracy of JNET type 2B lesions.

OBJECTIVE

The 261 lesions included 91 low-grade intramucosal neoplasia lesions (34.9%), 132 high-grade intramucosal neoplasia lesions (50.6%), 13 submucosal invasive cancer lesions (5.0%), and 25 deep submucosal invasive cancer lesions (9.6%). The coincidence rate between endoscopic prediction and pathological diagnosis of these lesions was 55.6% (145/ 261). The macroscopic type and size of the lesions were significantly associated with the diagnostic accuracy of JNET type 2B lesions (P < 0.001). There was a significant difference in the diagnostic accuracy among the lesions with different pit pattern types (P < 0.001).

OBJECTIVE

Both the macroscopic type and size affect the accuracy of endoscopic diagnosis of JNET type 2B colorectal lesions. JNET classification combined with pit pattern types can have better accuracy in predicting the pathological diagnosis of these lesions.

Comparison of the diagnostic efficacy of blue laser imaging with narrow band imaging for gastric cancer and precancerous lesions: a meta-analysis

BACKGROUND AND AIMS

novel endoscopic techniques including narrowband imaging (NBI) and blue laser imaging (BLI) have led to the improved detection of early stage gastric cancer and precancerous lesions. However, these techniques are not generally thought to be equivalent at present and BLI is generally considered as superior to NBI. Therefore, this comprehensive meta-analysis aimed to definitively compare the diagnostic efficacy of NBI and BLI for the diagnosis of gastric cancer and precancerous lesions.

METHODS

relevant articles were identified via searches of the PubMed, Web of Science, Embase and Cochrane Library databases from their inception until October 2019. In total, 28 relevant studies were identified and incorporated into the meta-analysis. RevMan5.3 was used to assess the relative diagnostic efficacy of these two imaging modalities in these studies. The threshold was assessed using Meta-DiSc 1.4 and STATA 14.0 for bivariate regression modeling of pooled studies.

RESULTS

the pooled sensitivity of BLI for gastric cancer was 0.89 (0.80, 0.95) and the specificity was 0.92 (0.76, 0.98). The pooled sensitivity of NBI for gastric cancer was 0.83 (0.75, 0.89) and the specificity was 0.95 (0.91, 0.97). The pooled sensitivity of BLI for precancerous lesions was 0.81 (0.71, 0.87) and the specificity was 0.90 (0.80, 0.96). The pooled sensitivity of NBI for precancerous lesions was 0.80 (0.75, 0.85) and the specificity was 0.88 (0.77, 0.94).

CONCLUSIONS

this study showed that both BLI and NBI have a very high diagnostic efficacy for the detection of gastric cancer and precancerous lesions, the sensitivity and specificity of these two approaches were similar.

Systematic Review on Optical Diagnosis of Early Gastrointestinal Neoplasia

BACKGROUND

Meticulous endoscopic characterization of gastrointestinal neoplasias (GN) is crucial to the clinical outcome. Hereby the indication and type of resection (endoscopically, en-bloc or piece-meal, or surgical resection) are determined. By means of established image-enhanced (IEE) and magnification endoscopy (ME) GN can be characterized in terms of malignancy and invasion depth. In this context, the statistical evidence and accuracy of these diagnostic procedures should be elucidated. Here, we present a systematic review of the literature.

RESULTS

21 Studies could be found which met the inclusion criteria. In clinical prospective trials and meta-analyses, the diagnostic accuracy of >90% for characterization of malignant neoplasms could be documented, if ME with IEE was used in squamous cell esophageal cancer, stomach, or colonic GN.

CONCLUSIONS

Currently, by means of optical diagnosis, today's gastrointestinal endoscopy is capable of determining the histological subtype, exact lateral spread, and depth of invasion of a lesion. The prerequisites for this are an exact knowledge of the anatomical structures, the endoscopic classifications based on them, and a systematic learning process, which can be supported by training courses. More prospective clinical studies are required, especially in the field of Barrett's esophagus and duodenal neoplasia.

Colonoscopy screening and surveillance guidelines

The Colonoscopy Screening and Surveillance Guidelines were developed by the Japan Gastroenterological Endoscopy Society as basic guidelines based on the scientific methods. The importance of endoscopic screening and surveillance for both detection and post-treatment follow-up of colorectal cancer has been recognized as essential to reduce disease mortality. There is limited high-level evidence in this field; therefore, we had to focus on the consensus of experts. These clinical practice guidelines consist of 20 clinical questions and eight background knowledge topics that have been determined as the current guiding principles.

Impact of linked-color imaging on colorectal adenoma detection

BACKGROUND AND AIMS

Linked-color imaging (LCI) is a new technology that emphasizes changes in mucosal color by providing clearer and brighter images, thus allowing red and white areas to be visualized more clearly. We investigated whether LCI increases the detection of colorectal adenomas compared with white-light imaging (WLI) and blue-laser imaging (BLI)-bright.

METHODS

Consecutive patients undergoing colonoscopy were randomized (1:1:1) into examination by WLI, BLI-bright, or LCI during withdrawal of the colonoscope. The adenoma detection rate (ADR), mean number of adenomas per patient, and withdrawal time were evaluated. The lesions were evaluated according to size, morphology, location, and histology.

RESULTS

A total of 379 patients were randomized, and 412 adenomas were detected. The ADR was 43.2%, 54.0%, and 56.9% for WLI, BLI-bright, and LCI, respectively, and was significantly higher in the LCI group than in the WLI group (P = .03). No significant difference was observed between LCI and BLI-bright (P = .71) or BLI-bright and WLI (P = .09). The mean number of adenomas per patient was 0.82, 1.06, and 1.38 for WLI, BLI-bright, and LCI, respectively, with a significant difference between LCI and WLI (P = .03). Withdrawal time did not differ among the groups. A total of 102 adenomas were detected by WLI, 131 by BLI-bright, and 179 by LCI. LCI provided a higher rate of detection of adenomas ≤5 mm in size than WLI (P = .02), with a borderline significance for a higher detection of sessile serrated adenomas (P = .05). Nonpolypoid adenomas were more commonly located in the right colon segment and polypoid adenomas in the left colon segment, with a significant difference only between BLI-bright (P < .01) and LCI (P = .03).

CONCLUSIONS

Our findings show that LCI increases the detection of colorectal adenomas during colonoscopy. (Clinical trial registration number: RBR-9xg6dx.).