Appearance of enhanced tissue features in narrow-band endoscopic imaging

Three-dimensional optically cleared tissue imaging for analyzing endoscopic images of gastrointestinal neoplasms (with video)

OBJECTIVES

To develop a procedure that matches magnifying endoscopic images with narrow-band imaging to 3D tissue structures using a tissue-clearing technique and to qualitatively and quantitatively analyze specified structures in gastrointestinal neoplasms.

METHODS

Endoscopically resected formalin-fixed paraffin-embedded gastrointestinal tissues (three esophagus, four stomach, seven colon) were made transparent by ethyl cinnamate. They were then subjected to fluorescent staining of nuclei and blood vessels followed by 3D imaging using a confocal laser scanning microscope. A one-to-one correspondence between magnifying endoscopic and 3D reconstructed images was established using vessels and crypts with characteristic shapes as guides, and the depth and caliber of specified vessels were measured.

RESULTS

All tissues were optically cleared, which allowed 3D visualization of vascular structures and nuclei in all layers. In the esophagus, intraepithelial papillary capillary loops and subepithelial capillary networks were identified. In the upper part of the stomach, polygonal subepithelial capillary loops surrounding the pits were observed, while in the lower part, surface epithelium with ridge-like structures and coiled vessels were observed. A honeycomb pit structure and surrounding vascular structures were identified in the colon. Quantitative analysis showed the various contrasts of a single continuous vessel in the endoscopic image were due to different depths at which the vessel tortuously ran.

CONCLUSION

We established a procedure to allow one-to-one correspondence between magnifying endoscopic and 3D reconstructed images and to measure the depth and caliber of endoscopically visualized vessels of interest. This method is expected to improve endoscopic diagnosis and further the development of endoscopic imaging technologies.

Multimodal generative AI for interpreting 3D medical images and videos

This perspective proposes adapting video-text generative AI to 3D medical imaging (CT/MRI) and medical videos (endoscopy/laparoscopy) by treating 3D images as videos. The approach leverages modern video models to analyze multiple sequences simultaneously and provide real-time AI assistance during procedures. The paper examines medical imaging's unique characteristics (synergistic information, metadata, and world model), outlines applications in automated reporting, case retrieval, and education, and addresses challenges of limited datasets, benchmarks, and specialized training.

Risk prediction model for precancerous gastric lesions based on magnifying endoscopy combined with narrow-band imaging features

Background

This study aimed to construct and validate diagnostic models for the Operative Link on Gastritis Assessment (OLGA) and Operative Link on Gastric Intestinal Metaplasia Assessment (OLGIM) staging systems using three different methodologies based on magnifying endoscopy with narrow-band imaging (ME-NBI) features, to evaluate model performance, and to analyse risk factors for high-risk OLGA/OLGIM stages.

Methods

We enrolled 356 patients who underwent white-light endoscopy and ME-NBI at the Department of Gastroenterology, Dongzhimen Hospital, Beijing University of Chinese Medicine, between January 2022 and September 2023. Clinical data were recorded. Chi-square or Fisher's exact tests were used to analyse differences in endoscopic features between OLGA/OLGIM stages. Variables showing statistical significance underwent collinearity diagnosis before model inclusion. We constructed predictive models using Bayesian stepwise discrimination, random forest, and XGBoost algorithms. Receiver operating characteristic (ROC) curves were plotted using Python 3.12.4. Model accuracy, area under the ROC curve (AUC), sensitivity, and specificity were calculated for comprehensive validation.

Results

All three models demonstrated excellent diagnostic performance, with random forest and XGBoost models showing marginally superior accuracy, AUC values, and sensitivity compared with the Bayesian stepwise discrimination model. For OLGA staging, the AUC values were 0.928, 0.958, and 0.966, with accuracies of 0.854, 0.902, and 0.918 for Bayesian, random forest, and XGBoost models, respectively. For OLGIM staging, the corresponding AUC values were 0.924, 0.975, and 0.979, with accuracies of 0.910, 0.938, and 0.927. Risk factors for high-risk OLGA included lesion location (subcardial and lower body greater curvature), intestinal metaplasia patches, lesion size, demarcation line (DL), and margin regularity of micro-capillary demarcation line (MCDL). Risk factors for high-risk OLGIM included Helicobacter pylori infection status, mucosal condition, lesion location (lesser curvature and lower body greater curvature), erosion, lesion size, DL, vessel and epithelial classification (VEC), white globe appearance (WGA), and MCDL margin regularity.

Conclusions

All three models demonstrated robust accuracy and predictive capability, confirming that conventional white-light endoscopy combined with ME-NBI features provides valuable diagnostic reference for clinical risk assessment of precancerous gastric lesions.

Linked color imaging and upper gastrointestinal neoplasia

White light imaging (WLI) can sometimes miss early upper gastrointestinal (UGI) neoplasms, particularly minimal changes and flat lesions. Moreover, endoscopic diagnosis of UGI neoplasia is strongly influenced by the condition of the surrounding mucosa. Recently, image-enhanced endoscopy techniques have been developed and used in clinical practice; one of which is linked color imaging (LCI), which has an expanded color range for better recognition of slight differences in mucosal color and enables easy diagnosis and differentiation of noncancerous mucosa from carcinoma. LCI does not require magnified observation and can clearly visualize structures using an ultrathin scope; therefore, it is useful for screening and surveillance endoscopy. LCI is particularly useful for detecting gastric cancer after Helicobacter pylori eradication, which accounts for most gastric cancers currently discovered, and displays malignant areas in orange or orange-red surrounded by intestinal metaplasia in lavender. Data on the use of convolutional neural network and computer-aided diagnosis with LCI for UGI neoplasm detection are currently being collected. Further studies are needed to determine the clinical role of LCI and whether it can replace WLI.

Can optical evaluation distinguish between T1a and T1b esophageal adenocarcinoma: an international expert interobserver agreement study

BACKGROUND

 Piecemeal endoscopic mucosal resection (EMR) is an acceptable technique for T1a esophageal adenocarcinoma, but en bloc R0 excision is advocated for T1b disease as it may offer a potential cure and mitigate recurrence. Thus, distinguishing between T1a and T1b disease is imperative under current treatment paradigms. We investigated whether expert Barrett's endoscopists could make this distinction based on optical evaluation.

METHODS

 Endoscopic images of histologically confirmed high grade dysplasia (HGD), T1a, and T1b disease (20 sets for each) were compiled from consecutive patients at a single institution. Each set contained four images including an overview, a close-up in high definition white light, a near-focus magnification image, and a narrow-band image. Experts predicted the histology for each set.

RESULTS

 19 experts from 8 countries (Australia, USA, Italy, Netherlands, Germany, Canada, Belgium, and Portugal) participated. The majority had been practicing for > 20 years, with a median (interquartile range) annual case volume of 50 (18-75) for Barrett's EMR and 25 (10-45) for Barrett's endoscopic submucosal dissection. Esophageal adenocarcinoma (T1a/b) could be distinguished from HGD with a pooled sensitivity of 89.1 % (95 %CI 84.7-93.4). T1b adenocarcinoma could be predicted with a pooled sensitivity of 43.8 % (95 %CI 29.9-57.7). Fleiss' kappa was 0.421 (95 %CI 0.399-0.442; P < 0.001), indicating fair-to-moderate agreement.

CONCLUSIONS

 Expert Barrett's endoscopists could reliably differentiate T1a/T1b esophageal adenocarcinoma from HGD. Despite fair-to-moderate agreement for T staging, T1b disease could not be reliably distinguished from T1a disease. This may impact clinical decision making and selection of endoscopic techniques.

Transesophageal Echocardiography-Related Complications During Mitral Valve Repair in Dogs

BACKGROUND

Transesophageal echocardiography (TEE) is an indispensable modality in cardiac surgery; however, the complications associated with its use in veterinary clinical settings remain unclear.

HYPOTHESIS/OBJECTIVES

To investigate the complications associated with TEE probe manipulation during mitral valve repair in dogs and identify the risk factors for new mucosal injuries.

ANIMALS

This prospective study evaluated 60 client-owned dogs that underwent TEE to support mitral valve repair.

METHODS

Esophageal endoscopy was performed twice-once after anesthesia induction and once before extubation-to assess esophageal mucosal injuries during the procedure. The type of injury was classified as 'complex' (intramural hematoma and mucosal laceration), 'minor' (petechiae and ecchymosis), or 'minute' (visible only on narrowband imaging) lesions. During the surgery, TEE was performed three times. Hemodynamics were evaluated before the initial TEE insertion and immediately after it was removed.

RESULTS

Of the 60 dogs, newly detected mucosal lesions were observed in 20 dogs and classified as 'minor' in four and 'minute' in 16 dogs. These 'minute' lesions were not visible with conventional endoscopy, and no 'complex' lesions were identified. No significant factors were associated with the presence of mucosal lesions. After TEE insertion, systolic blood pressure decreased from 95 ± 13 mmHg to 92 ± 11 mmHg (p = 0.008), and heart rate decreased from 128 ± 25 bpm to 123 ± 24 bpm (p < 0.001).

CONCLUSIONS AND CLINICAL IMPORTANCE

Intraoperative TEE results in a low incidence of esophageal mucosal injuries. Hemodynamic changes could occur during TEE manipulation, underscoring the need for close monitoring.

Utilizing Narrow Band Imaging for Early Detection of Recurrence in Follow-Up Patients with Head and Neck Squamous Cell Carcinoma Treated with Curative Intent Using Radiotherapy/Chemo-Radiotherapy: Enhancing Detection and Patient Outcomes

Head and Neck squamous cell carcinoma (HNSCC) is one of the most common cancer in developing countries. Most of the patients present with advanced disease and requires rigorous treatment. Routine follow up of the patient is required to detect any recurrence which will substantially affect overall survival of the patient. Narrow Band Imaging is one of the advanced endoscopic modalities which can be used for assessment of the patients during follow-up along with White light examination (WLE) and WB PETCT. An observational study to determine the efficacy and diagnostic accuracy of NBI in early detection of recurrence in follow-up patients with HNSCC was conducted comparing it with WLE, WB-PETCT and HPE. 60 patients who received definitive radiotherapy /Chemoradiotherapy (RT/CRT) for HNSCC were followed up for a period of 12 months with WLE, NBI, WB PETCT and was compared with HPE. NBI demonstrated higher sensitivity (95.45%) and specificity (97.37%) compared to WLE, which had sensitivity and specificity of 77.27% and 92.11%, respectively. NBI also had superior diagnostic accuracy (96.67%) versus white light (86.67%).WB-PETCT had sensitivity of 95.45% and specificity of 92.11% with a diagnostic accuracy of 93.33% for detecting local recurrences. NBI is a more sensitive and accurate tool for detecting early recurrences in HNSCC post RT/CRT, improving patient outcomes through timely intervention. Proper training and standardized interpretation protocols are essential for maximizing its clinical utility.

Precision Imaging for Early Detection of Esophageal Cancer

Early detection of early-stage esophageal cancer (ECA) is crucial for timely intervention and improved treatment outcomes. Hyperspectral imaging (HSI) and artificial intelligence (AI) technologies offer promising avenues for enhancing diagnostic accuracy in this context. This study utilized a dataset comprising 3984 white light images (WLIs) and 3666 narrow-band images (NBIs). We employed the Yolov5 model, a state-of-the-art object detection algorithm, to predict early ECA based on the provided images. The dataset was divided into two subsets: RGB-WLIs and NBIs, and four distinct models were trained using these datasets. The experimental results revealed that the prediction performance of the training model was notably enhanced when using HSI compared to general NBI training. The HSI training model demonstrated an 8% improvement in accuracy, along with a 5-8% enhancement in precision and recall measures. Notably, the model trained with WLIs exhibited the most significant improvement. Integration of HSI with AI technologies improves the prediction performance for early ECA detection. This study underscores the potential of deep learning identification models to aid in medical detection research. Integrating these models with endoscopic diagnostic systems in healthcare settings could offer faster and more accurate results, thereby improving overall detection performance.

Optimizing cystoscopy and TURBT: enhanced imaging and artificial intelligence

Diagnostic cystoscopy in combination with transurethral resection of the bladder tumour are the standard for the diagnosis, surgical treatment and surveillance of bladder cancer. The ability to inspect the bladder in its current form stems from a long chain of advances in imaging science and endoscopy. Despite these advances, bladder cancer recurrence and progression rates remain high after endoscopic resection. This stagnation is a result of the heterogeneity of cancer biology as well as limitations in surgical techniques and tools, as incomplete resection and provider-specific differences affect cancer persistence and early recurrence. An unmet clinical need remains for solutions that can improve tumour delineation and resection. Translational advances in enhanced cystoscopy technologies and artificial intelligence offer promising avenues to overcoming the progress plateau.

Significance of Endoscopic Redness of Duodenum in Health Checkup

Background and Aim

It is important for endoscopist to diagnose the lesion redness. In this study, we focused on the redness of duodenal bulb. We objectively analyzed the changes in redness of the duodenal bulb using linked color imaging (LCI) with chromatic indicators.

Methods

Seven endoscopists observed the duodenal bulb with white light imaging (WLI) and LCI, and evaluated them by visual analogue scale (VAS) for the degree of redness. The difference in VAS between WLI and LCI was defined as ΔVAS. All images were quantified by the Comission Internationale de l'Eclariage-L*a*b* color space. Values related to color differences (ΔE*, ΔL*, Δa*, and Δb*) were calculated from the two images of WLI and LCI. Multiple regression analysis was performed for the factors with the health checkup correlated with ΔVAS and the correlation between ΔVAS and ΔE*, ΔL*, Δa*, and Δb* was also examined.

Results

The analysis prospectively included 1144 examinees. In multiple regression analysis, it revealed that sex (β = 0.5847, p < 0.0001) and metabolic syndrome (β = 0.4138, p = 0.0012) were the factors independently influenced ΔVAS. And only Δa*, a chromatic index for changes in the degree of redness, showed a statistically and considerably positive correlation with ΔVAS (r = 0.4529, p < 0.0001).

Conclusion

To evaluate the difference in the degree of redness between WLI and LCI of duodenal bulb in esophagogastroduodenoscopy may help in early detection of metabolic syndrome, which rarely has symptoms.

The Recurrence Rates at Three Years for the Conservatively Managed UTUC Cases Using NBI-Assisted Flexible Ureteroscopy and Holmium Laser Vaporization

Background and Objectives: This study aimed to evaluate the recurrence rates at three years for upper tract urothelial carcinoma (UTUC) cases managed conservatively, using Narrow Band Imaging (NBI)-assisted flexible ureteroscopy and Holmium laser vaporization. Materials and Methods: The study group included 61 patients who were diagnosed with NBI-assisted visualization with superficial pyelo-calyceal urothelial tumor lesions, treated conservatively by the flexible ureteroscopic approach and Holmium laser vaporization, also assisted by NBI. This was compared with a control group with the same number of cases, which underwent the same procedure, but without NBI technology. Recurrence rates, the rate of patients who underwent nephroureterectomy, and cancer-specific survival were compared. Results: The relapse rate at 1 year was 3.3% in the study group, and respectively 8.2% in the control group (p < 0.05). Depending on the histological characteristics, at 1 year the relapse rates in the study group were 1.8% in patients with low-grade tumors and 20% in those with high-grade tumors. At 3 years, the relapse rate was 11.5% in the study group versus 18% in the control group, (p < 0.05): 7.1% in patients with low-grade lesions and 40% in patients with high-grade lesions versus 21.4% in patients with low-grade lesions and 100% in patients with high-grade lesions (both arms with statistically significant differences, p < 0.05). Cancer-specific survival was 93.4% in the study group versus 86.9% in the control group (p < 0.05). Conclusions: The recurrence rates at three years for the UTUC cases managed conservatively, using NBI-assisted flexible ureteroscopy and Holmium laser vaporization, were lower than in patients treated by the same technique without NBI assistance, both in low- and high-grade tumors. Cancer-specific survival was also significantly improved by the association of NBI visualization during diagnosis and laser vaporization.

Narrow band imaging in oral cancer did not improve visualisation of the tumour borders: a prospective cohort study

BACKGROUND

In oral cancers, tumour borders are typically defined by white light (WL). Narrow-band imaging (NBI) is an optical endoscopic technique commonly used for the larynx and for cancers of unknown primary. However, evidence for using NBI in oral cancers is insufficient.

AIMS/OBJECTIVES

We investigated whether NBI is a better predictor of the true mucosal tumour borders than WL in oral cancers. Additionally, we examined the agreement between NBI-based Takano intrapapillary capillary loop classifications and pathology reports.

MATERIALS AND METHODS

In this prospective study, the tumour borders were assessed by both NBI and WL at the time of surgical resection and then compared. Pathology reports of the examined areas were used as gold standard.

RESULTS

Forty-nine participants were included. After exclusion of 15 patients due to missing data, 34 were included in analyses. In 26.5% of the assessments, the tumour borders defined by NBI were outside the borders defined by WL. However, 55.5% of these were false-positives.

CONCLUSIONS AND SIGNIFICANCE

The delineation of mucosal tumour borders in oral cancers by NBI was not better than that by WL in this study. Several methodological challenges may have influenced the findings of this study, similar to the limitations reported in previous studies.

Correlation of Narrow Band Imaging Patterns with Histopathology Reports in Head and Neck Lesions

Introduction

Head and neck malignancies are associated with poor prognosis and poor quality-of-life if detected late. Narrow-Band-Imaging(NBI) is one of the important tools, which helps in detecting these lesions earlier. By using narrow-wavelength(400-550 nm) it enhances the mucosal and submucosal vascularity against the pale mucosal background which helps us detecting benign, pre-malignant and malignant lesions.

Objective

The objective of this study was to evaluate the accuracy of NBI in the diagnosis of various mucosal lesions of head and neck region and its correlation with the histopathology reports.

Materials and Methods

This was a prospective diagnostic study conducted between June 2020 - June 2022 where 118 patients(oral cavity-28, laryngeal-87,and hypopharyngeal-3) who fulfilled the inclusion and exclusion criteria were recruited. All-118-patients underwent NBI endoscopy under local/general anaesthesia followed by biopsies from the most suspicious-areas. Type of vascular-pattern noted from NBI and their respective histopathological reports were correlated.

Results

The mean age was 53.28 ± 1.24 years ranging from 16 to 88 years. The sensitivity, specificity, Positive-Predictive-Value(PPV) and Negative-Predictive-Value(NPV) in detecting benign lesions were 100%, 90%, 74% and 100% respectively. The sensitivity, specificity, PPV and NPV in detecting premalignant lesions were 70%, 92%, 56% and 96% respectively. The sensitivity, specificity, PPV and NPV in detecting malignant lesions were 83%,97.5%, 98.5% and 97.5% respectively. NBI has a strong association with the histopathological reports, which is statistically significant(p-value < 0.001).

Conclusion

NBI has high specificity and negative predictive value in detecting and classifying various mucosal lesions of head-neck region. Its findings had a strong correlation with histopathological reports.

Imaging colonic polyps in 2024

Screening colonoscopy and polypectomy are the cornerstone in decreasing the incidence and mortality of colorectal cancer. Despite the low incidence of colorectal cancer in India, there has been a rising trend in the incidence of colonic polyps and cancer over the last decade. It is, hence, imperative that we are well equipped in the management of colonic polyps. Adequate training in the detection and characterization of polyps to aid in their management is necessary. Detection of polyps can be increased by adhering to the standards of colonoscopy, including good bowel preparation, cecal intubation rate, adequate withdrawal time and use of distal attachment devices. A detected polyp needs optimal characterization to predict histology in real time and decide on the management strategies. Characterization of the polyps requires high-definition-white light endoscopy and/or image-enhanced endoscopy (dye based or digital). Various factors that help in predicting histology include size, location and morphology of the polyp and the pit pattern, vascular and surface pattern of the polyp. Polyps can be differentiated as neoplastic or non-neoplastic with reasonable accuracy with the above features. Prediction of advanced pathology including high-grade dysplasia and deep sub-mucosal invasion is essential, as it helps in deciding if the lesion is amenable to endotherapy and the technique of endoscopic resection. Adequate training in image-enhanced endoscopy is necessary to assess advanced pathology in polyps. Technology pertaining to image-enhanced endoscopy includes narrow banding imaging and blue laser imaging; newer variations are being introduced every few years making it necessary to be abreast with growing information. The recent advances in gastrointestinal (GI) endoscopy with the advent of endocytoscopy and artificial intelligence seem promising and are predicted to be the future of GI endoscopy.

Endoscopic detection and diagnostic strategies for minute gastric cancer: A real-world observational study

BACKGROUND

Minute gastric cancers (MGCs) have a favorable prognosis, but they are too small to be detected by endoscopy, with a maximum diameter ≤ 5 mm.

AIM

To explore endoscopic detection and diagnostic strategies for MGCs.

METHODS

This was a real-world observational study. The endoscopic and clinicopathological parameters of 191 MGCs between January 2015 and December 2022 were retrospectively analyzed. Endoscopic discoverable opportunity and typical neoplastic features were emphatically reviewed.

RESULTS

All MGCs in our study were of a single pathological type, 97.38% (186/191) of which were differentiated-type tumors. White light endoscopy (WLE) detected 84.29% (161/191) of MGCs, and the most common morphology of MGCs found by WLE was protruding. Narrow-band imaging (NBI) secondary observation detected 14.14% (27/191) of MGCs, and the most common morphology of MGCs found by NBI was flat. Another three MGCs were detected by indigo carmine third observation. If a well-demarcated border lesion exhibited a typical neoplastic color, such as yellowish-red or whitish under WLE and brownish under NBI, MGCs should be diagnosed. The proportion with high diagnostic confidence by magnifying endoscopy with NBI (ME-NBI) was significantly higher than the proportion with low diagnostic confidence and the only visible groups (94.19% > 56.92% > 32.50%, P < 0.001).

CONCLUSION

WLE combined with NBI and indigo carmine are helpful for detection of MGCs. A clear demarcation line combined with a typical neoplastic color using nonmagnifying observation is sufficient for diagnosis of MGCs. ME-NBI improves the endoscopic diagnostic confidence of MGCs.

Characteristic endoscopic findings in Helicobacter pylori diagnosis in clinical practice

INTRODUCTION

Helicobacter pylori is a major risk factor for gastric cancer. In addition to eradication therapy, early-phase detection of gastric cancer through screening programs using high-vision endoscopy is also widely known to reduce mortality. Although European and US guidelines recommend evaluation of atrophy and intestinal metaplasia by high-vision endoscopy and pathological findings, the guideline used in Japan - the Kyoto classification of gastritis - is based on endoscopic evaluation, and recommends the grading of risk factors. This system requires classification into three endoscopic groups: H. pylori-negative, previous H. pylori infection (inactive gastritis), and current H. pylori infection (active gastritis). Major endoscopic findings in active gastritis are diffuse redness, enlarged folds, nodularity, mucosal swelling, and sticky mucus, while those in H pylori-related gastritis - irrespective of active or inactive status - are atrophy, intestinal metaplasia, and xanthoma.

AREAS COVERED

This review describes the endoscopic characteristics of current H. pylori infection, and how characteristic endoscopic findings should be evaluated.

EXPERT OPINION

Although the correct evaluation of endoscopic findings related to H. pylori remains necessary, if findings of possible infection are observed, it is important to diagnose infection by detection methods with high sensitivity and specificity, including the stool antigen test and urea breath test.

Assessing the Efficacy of the Spectrum-Aided Vision Enhancer (SAVE) to Detect Acral Lentiginous Melanoma, Melanoma In Situ, Nodular Melanoma, and Superficial Spreading Melanoma

Skin cancer is the predominant form of cancer worldwide, including 75% of all cancer cases. This study aims to evaluate the effectiveness of the spectrum-aided visual enhancer (SAVE) in detecting skin cancer. This paper presents the development of a novel algorithm for snapshot hyperspectral conversion, capable of converting RGB images into hyperspectral images (HSI). The integration of band selection with HSI has facilitated the identification of a set of narrow band images (NBI) from the RGB images. This study utilizes various iterations of the You Only Look Once (YOLO) machine learning (ML) framework to assess the precision, recall, and mean average precision in the detection of skin cancer. YOLO is commonly preferred in medical diagnostics due to its real-time processing speed and accuracy, which are essential for delivering effective and efficient patient care. The precision, recall, and mean average precision (mAP) of the SAVE images show a notable enhancement in comparison to the RGB images. This work has the potential to greatly enhance the efficiency of skin cancer detection, as well as improve early detection rates and diagnostic accuracy. Consequently, it may lead to a reduction in both morbidity and mortality rates.

Application of narrow band imaging in the diagnosis of pharyngeal tumors

BACKGROUND

Narrow-band imaging (NBI) endoscopy is used in various tumor detection and is important in detecting early tumors.

OBJECTIVE

To explore the application value of NBI endoscopy in diagnosing pharyngeal tumors.

MATERIAL AND METHODS

Ninety-one patients with pharyngeal masses who attended the Department of Otorhinolaryngology, Head and Neck Surgery in Gansu Provincial Hospital from January 2023 to February 2024 were selected, and NBI and white light (WL) endoscopy were applied to examine the pharynx and the relationship between the two was observed. SPSS 25.0 software was used for statistical analysis.

RESULTS

The sensitivity of NBI endoscopy for diagnosing laryngeal malignant lesions was 92.0 %, the specificity was 93.0 %, the positive predictive value was 88.5 %, and the negative predictive value was 95.2 %, with a high degree of concordance between the results of NBI endoscopy and the pathology; WL endoscopy had a sensitivity of 64.0 %, a specificity of 76. 7 %, a positive predictive value of 61.5 %, and a negative predictive value of 78.6 %, with WL endoscopic findings had moderate concordance with pathology. The diagnostic accuracy of NBI endoscopy was higher than that of WL endoscopy for both benign and malignant lesions and precancerous lesions.

CONCLUSION

NBI endoscopy can detect laryngeal cancer lesions more accurately.

Novel physiological analysis using blood flow velocity for colonic polyps: Pilot study

Real-time visualization of red blood cell flow inside subepithelial microvessels is performed with magnifying endoscopy. However, microvascular blood flow velocity in the colorectum has not been investigated. Here, we aimed to evaluate the blood flow velocity of microvessels of colonic polyps and to compare it with that of surrounding mucosa. We examined 50 lesions, including 30 adenomas (ADs) and 20 hyperplastic polyps (HPs). Blood flow velocities of lesions and their surrounding mucosa were evaluated using magnifying blue laser imaging (BLI) prior to endoscopic resection. Calculation of mean blood flow velocities was based on mean movement distance of one tagged red blood cell using split video images of magnifying BLI. Mean microvascular blood flow velocity was significantly lower in ADs (1.65±0.66 mm/sec; range 0.46-2.90) than in HPs (2.83±1.10 mm/sec; 1.07-4.50) or the surrounding mucosa (3.73±1.11 mm/sec; 1.80-6.20; P <0.001). The blood flow velocity rate compared with the surrounding mucosa was significantly lower in ADs (0.41±0.16; 0.10-0.82) than in HPs (0.89±0.25; 0.46-1.51; P <0.001). We found that mean microvascular blood flow velocity was significantly lower in ADs than in HPs and the surrounding non-neoplastic mucosa. These findings indicate that a novel dynamic approach with microvascular blood flow velocity using magnifying endoscopy may be useful in assessing physiological differences between ADs and HPs.

Surveillance esophagogastroduodenoscopy using linked color imaging and narrow-band imaging: A multicenter randomized controlled trial

BACKGROUND AND AIM

There has been no report on a direct comparison between linked color imaging (LCI) and second-generation narrow-band imaging (2G-NBI) for surveillance of epithelial neoplasms in the upper gastrointestinal tract (UGIT). The aim of this study was to verify the superiority of LCI to 2G-NBI for surveillance esophagogastroduodenoscopy and to clarify how each endoscopic system should be used.

METHODS

This study was conducted as an open-label, two-arm-parallel (1:1), multicenter, randomized controlled trial at six institutions. Patients aged 20-85 years with a treatment history of epithelial neoplasms in the UGIT were recruited. Patients were assigned to a 2G-NBI group and an LCI group, and esophagogastroduodenoscopy was performed with primary image-enhanced endoscopy followed by white light imaging (WLI). The primary endpoint was the detection rate of one or more epithelial neoplasms in the primary image-enhanced endoscopy. A WLI-detected epithelial neoplasm was defined as a lesion that was detected in only WLI.

RESULTS

A total of 372 patients in the 2G-NBI group and 378 patients in the LCI group were analyzed. Epithelial neoplasms in the UGIT were detected by 2G-NBI in 18 patients (4.6%) and were detected by LCI in 20 patients (5.3%) (P = 0.87). WLI-detected epithelial neoplasms were in 11 patients in the 2G-NBI group (3.0%) and in 1 patient in the LCI group (0.27%) (P = 0.003).

CONCLUSIONS

Linked color imaging did not show superiority to 2G-NBI for the detection of epithelial neoplasms. Also, the percentage of WLI-detected epithelial neoplasms in primary NBI was significantly higher than that in primary LCI.

First report from the International Evaluation of Endoscopic classification Japan NBI Expert Team: International multicenter web trial

OBJECTIVES

Narrow-band imaging (NBI) contributes to real-time optical diagnosis and classification of colorectal lesions. The Japan NBI Expert Team (JNET) was introduced in 2011. The aim of this study was to explore the diagnostic accuracy of JNET when applied by European and Japanese endoscopists not familiar with this classification.

METHODS

This study was conducted by 36 European Society of Gastrointestinal Endoscopy (ESGE) and 49 Japan Gastroenterological Endoscopy Society (JGES) non-JNET endoscopists using still images of 150 lesions. For each lesion, nonmagnified white-light, nonmagnified NBI, and magnified NBI images were presented. In the magnified NBI, the evaluation area was designated by region of interest (ROI). The endoscopists scored histological prediction for each lesion.

RESULTS

In ESGE members, the sensitivity, specificity, and accuracy were respectively 73.3%, 94.7%, and 93.0% for JNET Type 1; 53.0%, 64.9%, and 62.1% for Type 2A; 43.9%, 67.7%, and 55.1% for Type 2B; and 38.1%, 93.7%, and 85.1% for Type 3. When Type 2B and 3 were considered as one category of cancer, the sensitivity, specificity, and accuracy for differentiating high-grade dysplasia and cancer from the others were 59.9%, 72.5%, and 63.8%, respectively. These trends were the same for JGES endoscopists.

CONCLUSION

The diagnostic accuracy of the JNET classification was similar between ESGE and JGES and considered to be sufficient for JNET Type 1. On the other hand, the accuracy for Types 2 and 3 is not sufficient; however, JNET 2B lesions should be resected en bloc due to the risk of cancers and JNET 3 can be treated by surgery due to its high specificity.

A novel endoscopy image fusion system: combine white light imaging and compound band imaging

PURPOSE

White light imaging (WLI) is a commonly seen examination mode in endoscopy. The particular light in compound band imaging (CBI) can highlight delicate structures, such as capillaries and tiny structures on the mucosal surface. These two modes complement each other, and doctors switch between them manually to complete the examination. This paper proposes an endoscopy image fusion system to combine WLI and CBI.

METHODS

We add a real-time rotatable color wheel in the light source device of the AQ-200 endoscopy system to achieve rapid imaging of two modes at the same position of living tissue. The two images corresponding to the pixel level can avoid registration and lay the foundation for image fusion. We propose a multi-scale image fusion framework, which involves Laplacian pyramid (LP) and convolutional sparse representation (CSR) and strengthens the details in the fusion rule.

RESULTS

Volunteer experiments and ex vivo pig stomach trials are conducted to verify the feasibility of our proposed system. We also conduct comparative experiments with other image fusion methods, evaluate the quality of the fused images, and verify the effectiveness of our fusion framework. The results show that our fused image has rich details, high color contrast, apparent structures, and clear lesion boundaries.

CONCLUSION

An endoscopy image fusion system is proposed, which does not change the doctor's operation and makes the fusion of WLI and CBI optical staining technology a reality. We change the light source device of the endoscope, propose an image fusion framework, and verify the feasibility and effectiveness of our scheme. Our method fully integrates the advantages of WLI and CBI, which can help doctors make more accurate judgments than before. The endoscopy image fusion system is of great significance for improving the detection rate of early lesions and has broad application prospects.

Comprehensive advancement in endoscopy: optical design, algorithm enhancement, and clinical validation for merged WLI and CBI imaging

As endoscopic imaging technology advances, there is a growing clinical demand for enhanced imaging capabilities. Although conventional white light imaging (WLI) endoscopy offers realistic images, it often cannot reveal detailed characteristics of the mucosa. On the other hand, optical staining endoscopy, such as Compound Band Imaging (CBI), can discern subtle structures, serving to some extent as an optical biopsy. However, its image brightness is low, and the colors can be abrupt. These two techniques, commonly used in clinical settings, have complementary advantages. Nonetheless, they require different lighting conditions, which makes it challenging to combine their imaging strengths on living tissues. In this study, we introduce a novel endoscopic imaging technique that effectively combines the advantages of both WLI and CBI. Doctors don't need to manually switch between these two observation modes, as they can obtain the image information of both modes in one image. We calibrated an appropriate proportion for simultaneous illumination with the light required for WLI and CBI. We designed a new illumination spectrum tailored for gastrointestinal examination, achieving their fusion at the optical level. Using a new algorithm that focuses on enhancing specific hemoglobin tissue features, we restored narrow-band image characteristics lost due to the introduction of white light. Our hardware and software innovations not only boost the illumination brightness of the endoscope but also ensure the narrow-band feature details of the image. To evaluate the reliability and safety of the new endoscopic system, we conducted a series of tests in line with relevant international standards and validated the design parameters. For clinical trials, we collected a total of 256 sets of images, each set comprising images of the same lesion location captured using WLI, CBI, and our proposed method. We recruited four experienced clinicians to conduct subjective evaluations of the collected images. The results affirmed the significant advantages of our method. We believe that the novel endoscopic system we introduced has vast potential for clinical application in the future.

Correlation of narrow-band imaging findings using the Ni and European Laryngeal Society classification systems during in-office flexible laryngoscopy with histopathology

OBJECTIVE

This study used the European Laryngeal Society (2016) and Ni (2011 and 2019) classifications for narrow-band imaging and correlated the findings with histopathology.

METHODS

Retrospective analysis was conducted by retrieving data of patients who underwent micro-laryngoscopy for suspicious glottic lesions. The narrow-band imaging findings were classified using both classification systems. Retrieved histopathology report findings were correlated with narrow-band imaging data.

RESULTS

Using the European Laryngeal Society and Ni classifications, 37 (69.8 per cent) and 35 (66 per cent) patients, respectively, were suspected to have malignant lesions. Upon histopathology, 37 (69.8 per cent) lesions were malignant. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy using the European Laryngeal Society classification were 91.9 per cent, 81.3 per cent, 91.9 per cent, 81.3 per cent and 88.7 per cent, and using the Ni classification were 91.9 per cent, 93.8 per cent, 97.1 per cent, 83.3 per cent and 92.5 per cent, respectively.

CONCLUSION

The Ni classification had better specificity and accuracy. The European Laryngeal Society classification is simple to use and may serve as a useful screening tool. For optimum results, both European Laryngeal Society and Ni classifications may be used together, in that order.

Artificial Intelligence in endoscopy: A future poll

Artificial Intelligence [AI] has been a trendy topic in recent years, with many developed medical applications. In gastrointestinal endoscopy, AI systems include computer-assisted detection [CADe] for lesion detection as bleedings and polyps and computer-assisted diagnosis [CADx] for optical biopsy and lesion characterization. The technology behind these systems is based on a computer algorithm that is trained for a specific function. This function could be to recognize or characterize target lesions such as colonic polyps. Moreover, AI systems can offer technical assistance to improve endoscopic performance as scope insertion guidance. Currently, we believe that such technologies still lack legal and regulatory validations as a large sector of doctors and patients have concerns. However, there is no doubt that these technologies will bring significant improvement in the endoscopic management of patients as well as save money and time.

Advances in fibreoptic ductoscopy for the diagnosis and treatment of pathologic papillary overflow

Fibreoptic mammography is widely recognised as the first screening method for pathologic papillary overflow due to its significant advantages in the diagnosis of ductal dilatation, intraductal papilloma and intraductal carcinoma. The use of fibreoptic ductoscopic excisional biopsy techniques, such as biopsy needles, vacuum negative pressure aspiration, biopsy forceps and grasping baskets, has not been promoted largely due to their existing deficiencies. The imaging effect of fibreoptic ductoscopy compared with electronic ductoscopy is also one of the important factors limiting the progress of microscopic excisional biopsy techniques. Finding a more suitable operating space for electronic fibreoptic ductoscopy and the use of electrosurgical excision biopsy techniques should be the focus of research in view of achieving accurate diagnoses in electronic fibreoptic ductoscopy and microscopic excision biopsy. In this review, the development history, clinical application and existing problems of fibreoptic ductoscopy are reviewed and assessed to provide references for the clinical diagnosis and treatment of pathologic papillary overflow.

Vocal fold leukoplakia recurrence risk model

The paper aims to define the variables that elevate the risk of VFL recurrence after adequate primary treatment, and to present the Recurrence Risk Model with practical conclusions to handle pVFL and rVFL. Out of 207 patients with primary vocal fold leukoplakia (pVFL), in 41 (19.8%) recurrent VFL (rVFL) was diagnosed. All patients were assessed by using a trans-nasal flexible video-endoscope using white light, and NBI. The primary measure of our study was to investigate whether morphological features of pVFL in WL, vascular pattern in NBI, and primary histological findings could predict VFL recurrence. To create a model of risk factors, two methods were used: logistic regression and a conditional inference decision tree. The study showed smoking was the factor that significantly and most strongly increased the likelihood of rVFL, as well as the older age groups have a greater odds of rVFL. Types IV, V and VI, according to Ni 2019 classification, were associated with a significantly higher risk of rVFL. The algorithm combining patients' dependent variables and the combination of two classifications improves the predictive value of the presented VFL Recurrence Risk Model.

A comparison of the efficacy of narrow band imaging and contact endoscopy in an early diagnosis of squamous malignancies of the upper aerodigestive tract

Background

This study aims to compare the efficacy of narrow band imaging (NBI) endoscopy and contact endoscopy in early diagnosis of squamous malignancies of upper aerodigestive tract.

Methods

This study was of 18 months duration, sample size 50, and carried out at tertiary care hospital. The patients were subjected initially to NBI endoscopy followed by contact endoscopy. Thereafter, the lesion was biopsied and subjected to histopathological examination as is done routinely. The images obtained were analyzed based on criteria proposed by earlier studies and compared with histopathological examination as gold standard.

Results

The sensitivity, specificity, and negative predictive values of NBI in early diagnosis of squamous malignancies of upper aerodigestive tract were high and better than contact endoscopy.

Conclusion

Endoscopic NBI is a noninvasive and promising tool used for in vivo differentiation between malignant and nonmalignant lesions of upper aerodigestive tract by using morphology of mucosal capillaries and is more efficacious than contact endoscopy. It can be employed as part of routine ENT examination in outpatient departments; however, it has got a learning curve associated with it.

Endoscope Capsules: The Present Situation and Future Outlooks

This paper presents new perspectives on photonic technologies for capsule endoscopy. It first presents a review of conventional endoscopy (upper endoscopy and colonoscopy), followed by capsule endoscopy (CE), as well as their techniques, advantages, and drawbacks. The technologies for CEs presented in this paper include integration with the existing endoscopic systems that are commercially available. Such technologies include narrow-band imaging (NBI), photodynamic therapy (PDT), confocal laser endomicroscopy (CLE), optical coherence tomography (OCT), and spectroscopy in order to improve the performance of the gastrointestinal (GI) tract examination. In the context of NBI, two optical filters were designed and fabricated for integration into endoscopic capsules, allowing for the visualization of light centered at the 415 nm and 540 nm wavelengths. These optical filters are based on the principle of Fabry-Perot and were made of thin films of titanium dioxide (TiO2) and silicon dioxide (SiO2). Moreover, strategies and solutions for the adaptation of ECs for PDT are also discussed.

Comparison of narrow-band imaging with autofluorescence imaging for endoscopic detection of squamous cell carcinoma of the tonsil

PURPOSE

Early detection of mucosal neoplastic lesions is crucial for a patient's prognosis. This has led to the development of effective optical endoscopic diagnostic methods such as narrow band imaging (NBI) and autofluorescence (AFI). Independent of each other, both of these methods were proven useful in the detection of mucosal neoplasias. There are limited reported data comparing both methods for oropharyngeal cancer diagnostics. The aim of the study was to compare NBI and AFI endoscopic visualization of signs in identifying tonsillar squamous cell carcinoma (SCC) and assessing its extent and to determine whether the score was related to the evaluator's experience.

METHODS

Patients with tonsillar SCC underwent endoscopic pharyngeal examination using NBI and AFI. Fiftyseven video sequences of examinations of lesions proven to be SCC were evaluated by three reviewers. The accuracy of determination of lesion extent and visualization of its endoscopic signs of malignancy were evaluated.

RESULTS

Endoscopic visualization of tumour spread was significantly better using AFI than NBI (p = 0.0003). No significant difference was found between NBI and AFI in the visualization of endoscopic malignancy determining signs (p = 0.1405). No significant difference was found among the three reviewers in the visualization of tumour spread and for identifying malignancy-determining signs in NBI endoscopy or AFI endoscopy.

CONCLUSIONS

The results show that AFI obtained better results for assessing the extent of tonsillar cancers than NBI. Both methods were proven to be equal in the visualization of endoscopic malignancy-determining signs. Both are useful even for less experienced evaluators.

Revolutionizing healthcare by use of artificial intelligence in esophageal carcinoma - a narrative review

Esophageal cancer is a major cause of cancer-related mortality worldwide, with significant regional disparities. Early detection of precursor lesions is essential to improve patient outcomes. Artificial intelligence (AI) techniques, including deep learning and machine learning, have proved to be of assistance to both gastroenterologists and pathologists in the diagnosis and characterization of upper gastrointestinal malignancies by correlating with the histopathology. The primary diagnostic method in gastroenterology is white light endoscopic evaluation, but conventional endoscopy is partially inefficient in detecting esophageal cancer. However, other endoscopic modalities, such as narrow-band imaging, endocytoscopy, and endomicroscopy, have shown improved visualization of mucosal structures and vasculature, which provides a set of baseline data to develop efficient AI-assisted predictive models for quick interpretation. The main challenges in managing esophageal cancer are identifying high-risk patients and the disease's poor prognosis. Thus, AI techniques can play a vital role in improving the early detection and diagnosis of precursor lesions, assisting gastroenterologists in performing targeted biopsies and real-time decisions of endoscopic mucosal resection or endoscopic submucosal dissection. Combining AI techniques and endoscopic modalities can enhance the diagnosis and management of esophageal cancer, improving patient outcomes and reducing cancer-related mortality rates. The aim of this review is to grasp a better understanding of the application of AI in the diagnosis, treatment, and prognosis of esophageal cancer and how computer-aided diagnosis and computer-aided detection can act as vital tools for clinicians in the long run.

Scanning darkfield high-resolution microendoscope for label-free microvascular imaging

Characterization of microvascular changes during neoplastic progression has the potential to assist in discriminating precancer and early cancer from benign lesions. Here, we introduce a novel high-resolution microendoscope that leverages scanning darkfield reflectance imaging to characterize angiogenesis without exogenous contrast agents. Scanning darkfield imaging is achieved by coupling programmable illumination with a complementary metal-oxide semiconductor (CMOS) camera rolling shutter, eliminating the need for complex optomechanical components and making the system portable, low-cost (<$5,500) and simple to use. Imaging depth is extended by placing a gradient-index (GRIN) lens at the distal end of the imaging fiber to resolve subepithelial microvasculature. We validated the capability of the scanning darkfield microendoscope to visualize microvasculature at different anatomic sites in vivo by imaging the oral cavity of healthy volunteers. Images of cervical specimens resected for suspected neoplasia reveal distinct microvascular patterns in columnar and squamous epithelium with different grades of precancer, indicating the potential of scanning darkfield microendoscopy to aid in efforts to prevent cervical cancer through early diagnosis.

Assessment of Narrow Band Imaging Algorithm for Video Capsule Endoscopy Based on Decorrelated Color Space for Esophageal Cancer

Video capsule endoscopy (VCE) is increasingly used to decrease discomfort among patients owing to its small size. However, VCE has a major drawback of not having narrow band imaging (NBI) functionality. The current VCE has the traditional white light imaging (WLI) only, which has poor performance in the computer-aided detection (CAD) of different types of cancer compared to NBI. Specific cancers, such as esophageal cancer (EC), do not exhibit any early biomarkers, making their early detection difficult. In most cases, the symptoms are unnoticeable, and EC is diagnosed only in later stages, making its 5-year survival rate below 20% on average. NBI filters provide particular wavelengths that increase the contrast and enhance certain features of the mucosa, thereby enabling early identification of EC. However, VCE does not have a slot for NBI functionality because its size cannot be increased. Hence, NBI image conversion from WLI can presently only be achieved in post-processing. In this study, a complete arithmetic assessment of the decorrelated color space was conducted to generate NBI images from WLI images for VCE of the esophagus. Three parameters, structural similarity index metric (SSIM), entropy, and peak-signal-to-noise ratio (PSNR), were used to assess the simulated NBI images. Results show the good performance of the NBI image reproduction method with SSIM, entropy difference, and PSNR values of 93.215%, 4.360, and 28.064 dB, respectively.

Diagnostic validity and learning curve of non-NBI expert endoscopists in gastric intestinal metaplasia diagnosis

BACKGROUND

Endoscopists' experience influences narrow-band imaging (NBI)-guided gastric intestinal metaplasia (GIM) diagnostic performance. We aimed to evaluate the general gastroenterologists (GE) performance in NBI-guided GIM diagnosis compared to NBI experts (XP) and assess GEs' learning curve.

METHODS

A cross-sectional study was conducted between 10/2019 and 2/2022. Histology-proven GIM who underwent esophagogastroduodenoscopy (EGD) were randomly assessed by 2XPs or 3GEs. Endoscopists' performance on NBI-guided diagnoses were compared to the pathological diagnosis (gold standard) in five areas of the stomach according to the Sydney protocol. The primary outcome were GIM diagnosis validity scores of GEs compared to XPs. The secondary outcome was the minimum number of lesions required for GEs to achieve an accuracy of GIM diagnosis ≥ 80%.

RESULTS

One thousand one hundred and fifty-five lesions from 189 patients (51.3% male, mean age 66 ± 10 years) were examined. GEs performed EGD in 128 patients with 690 lesions. the GIM diagnosis sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of GEs compared to the XPs, were 91% vs.93%, 73% vs.83%, 79% vs.83%, 89% vs.93%, and 83% vs.88%, respectively. GEs demonstrated lower specificity (mean difference - 9.4%; 95%CI - 16.3, 1.4; p = 0.008) and accuracy (mean difference - 5.1%; 95%CI - 3.3, 6.3; p = 0.006) compared to XPs. After 100 lesions (50% GIM), GEs achieved an accuracy of ≥ 80% and all diagnostic validity scores were comparable to the XPs (p < 0.05 all).

CONCLUSIONS

Compared to XPs, GEs had lower specificity and accuracy for GIM diagnosis. The learning curve for a GE to achieve comparable performance to XPs would necessitate at least 50 GIM lesions. Created with BioRender.com.

The Pink Zone Pattern (PP) sign: A novel simple marker for early gastric cancer

BACKGROUND

We previously found a pink-colored change in early gastric cancer (EGC) lesions under magnifying endoscopy with narrow-band imaging (ME-NBI) and named it the "Pink Zoon Pattern" (PP) sign, which appeared independent of microvascular and microstructural changes. The aim of this study was to further investigate the characteristics of the PP sign in EGC.

METHODS

The consecutive patients with suspicious gastric lesions detected by ME-NBI and confirmed by pathology at Zhejiang Cancer Hospital between November 2020 and December 2021 were enrolled in the study. The suspicious lesions were observed and assessed by the "VS" system and the PP sign respectively.

RESULTS

We found that in the PP-positive group, 238 lesions (96.0%) were diagnosed as malignant. The overall accuracy, sensitivity, and specificity were 84.7%, 85.3%, and 81.8%. Among 164 EGC lesions diagnosed with low confidence (Grades 2, 3, and 4) using the VS system, the overall accuracy of PP to discriminate tumor from normal was 82.3%. The sensitivity and specificity were 82.7% and 81.5% respectively.

CONCLUSIONS

The PP sign could be a new simple sign for the diagnosis of EGC and as an effective supplement to VS system when using ME-NBI.

Systematic meta-analysis of computer-aided detection to detect early esophageal cancer using hyperspectral imaging

One of the leading causes of cancer deaths is esophageal cancer (EC) because identifying it in early stage is challenging. Computer-aided diagnosis (CAD) could detect the early stages of EC have been developed in recent years. Therefore, in this study, complete meta-analysis of selected studies that only uses hyperspectral imaging to detect EC is evaluated in terms of their diagnostic test accuracy (DTA). Eight studies are chosen based on the Quadas-2 tool results for systematic DTA analysis, and each of the methods developed in these studies is classified based on the nationality of the data, artificial intelligence, the type of image, the type of cancer detected, and the year of publishing. Deeks' funnel plot, forest plot, and accuracy charts were made. The methods studied in these articles show the automatic diagnosis of EC has a high accuracy, but external validation, which is a prerequisite for real-time clinical applications, is lacking.

Non-exposed endoscopic wall-inversion surgery with one-step nucleic acid amplification for early gastrointestinal tumors: Personal experience and literature review

BACKGROUND

Laparoscopic and endoscopic cooperative surgery is a safe, organ-sparing surgery that achieves full-thickness resection with adequate margins. Recent studies have demonstrated the safety and efficacy of these procedures. However, these techniques are limited by the exposure of the tumor and mucosa to the peritoneal cavity, which could lead to viable cancer cell seeding and the spillage of gastric juice or enteric liquids into the peritoneal cavity. Non-exposed endoscopic wall-inversion surgery (NEWS) is highly accurate in determining the resection margins to prevent intraperitoneal contamination because the tumor is inverted into the visceral lumen instead of the peritoneal cavity. Accurate intraoperative assessment of the nodal status could allow stratification of the extent of resection. One-step nucleic acid amplification (OSNA) can provide a rapid method of evaluating nodal tissue, whilst near-infrared laparoscopy together with indocyanine green can identify relevant nodal tissue intraoperatively.

AIM

To determine the safety and feasibility of NEWS in early gastric and colon cancers and of adding rapid intraoperative lymph node (LN) assessment with OSNA.

METHODS

The patient-based experiential portion of our investigations was conducted at the General and Oncological Surgery Unit of the St. Giuseppe Moscati Hospital (Avellino, Italy). Patients with early-stage gastric or colon cancer (diagnosed via endoscopy, endoscopic ultrasound, and computed tomography) were included. All lesions were treated by NEWS procedure with intraoperative OSNA assay between January 2022 and October 2022. LNs were examined intraoperatively with OSNA and postoperatively with conventional histology. We analyzed patient demographics, lesion features, histopathological diagnoses, R0 resection (negative margins) status, adverse events, and follow-up results. Data were collected prospectively and analyzed retrospectively.

RESULTS

A total of 10 patients (5 males and 5 females) with an average age of 70.4 ± 4.5 years (range: 62-78 years) were enrolled in this study. Five patients were diagnosed with gastric cancer. The remaining 5 patients were diagnosed with early-stage colon cancer. The mean tumor diameter was 23.8 ± 11.6 mm (range: 15-36 mm). The NEWS procedure was successful in all cases. The mean procedure time was 111.5 ± 10.7 min (range: 80-145 min). The OSNA assay revealed no LN metastases in any patients. Histologically complete resection (R0) was achieved in 9 patients (90.0%). There was no recurrence during the follow-up period.

CONCLUSION

NEWS combined with sentinel LN biopsy and OSNA assay is an effective and safe technique for the removal of selected early gastric and colon cancers in which it is not possible to adopt conventional endoscopic resection techniques. This procedure allows clinicians to acquire additional information on the LN status intraoperatively.

Narrow Band Imaging Technology: Role in the Detection of Recurrent Laryngeal and Hypopharyngeal Cancers Post-radiotherapy

To assess the diagnostic accuracy of NBI endoscopy for the diagnosis of early recurrent laryngeal and hypopharyngeal cancers after radiotherapy. The study was conducted over a period of two and a half years from June 2019 to February 2022 and included 123 post-RT patients with laryngeal and hypopharyngeal cancers. The patients were planned for endoscopy with white light and narrow-band imaging. The biopsy was carried out in NBI suspected lesions and sent for histopathological examination. The pathologist was blinded to the outcome of NBI and WLE results to eliminate observer bias. The age group most commonly affected in our study was 40-50 years. Out of the 123 patients, 106 were males and 17 were females. The overall Sensitivity, Specificity, Positive predictive value and Negative predictive value of NBI for malignant lesions were 90.6%, 99%, 95.2% and 98% respectively. NBI Technology is a first-rate diagnostic tool that can help in diagnosing early recurrent cancer lesions, especially after RT, in which the recurrence is otherwise difficult to differentiate from post-radiotherapy oedema. This technology can significantly reduce the rates of failure to detect cancers in early stages.

A comparative study of magnifying endoscopy with narrow-band image and endocytoscopy in the diagnosis of gastric neoplasm: a pilot study

BACKGROUND/AIMS

Endoscopic technologies have recently advanced to optimize the detection and diagnosis of gastric lesions. Endocytoscopy aids in the virtual realization of histology. Herein, we aimed to investigate gastric lesions using single-stain endocytoscopy and compare them using magnifying endoscopy with narrow-band imaging (ME-NBI) in terms of diagnostic yield in vivo.

METHODS AND METHODS

In the present prospective study, we registered 24 patients with gastric neoplasms and retrospectively reviewed their images. Three endoscopists reviewed the images of gastric neoplasms using white light, ME-NBI, and endocytoscopy. The diagnostic yield of endocytoscopy in early gastric cancer (EGC) was assessed using histopathology as the gold standard.

RESULTS

Endocytoscopy was performed in 24 patients with gastric neoplasms. Of these, 15 patients had adenocarcinomas, while nine patients had low-grade dysplasia. The sensitivity, specificity, and accuracy of endocytoscopy for EGC detection were reported as 80.0% [95% confidence interval (CI), 51.9-95.7], 66.7% (95% CI, 58.4-91.9), and 75.0% (95% CI, 53.3-90.2) by endoscopist A; 80.0% (95% CI, 51.9-95.7), 44.4% (95% CI, 13.7-78.8), and 66.7% (95% CI, 44.7-84.4) by endoscopist B; and 93.3% (95% CI, 68.1-99.8), 55.6% (95% CI, 21.2-86.3), and 79.2% (95% CI, 57.9-92.8) by endoscopist C; these findings were not inferior to NBI. The inter-observer agreement, κ statistic = 0.67 (95% CI, 0.43-0.90) was favorable.

CONCLUSION

Endocytoscopy aid in the diagnosis of EGC because of its better sensitivity and accuracy compared to NBI or white-light imaging. However, further large-scale studies are required to confirm our findings.

Determination of Correlated Color Temperature in Ex Vivo Porcine Eyes during Intraocular Illumination

(1) Background: In ophthalmic surgery, white light is mostly applied to illuminate the intraocular space, and ophthalmologists are comfortable working with it. Diaphanoscopic illumination changes the spectral composition of light, resulting in a change in the correlated color temperature (CCT) of the intraocular illumination. This color change makes it difficult for surgeons to recognize the structures in the eye. CCT during intraocular illumination has not yet been measured before, and it is the aim of this study to perform such measurement. (2) Methods: CCT was measured inside ex vivo porcine eyes during diaphanoscopic illumination and endoillumination using a current ophthalmic illumination system with a detection fiber inside the eye. By applying pressure on the eye with a diaphanoscopic fiber, the dependency of CCT on pressure was examined. (3) Results: The intraocular CCT values during endoillumination were 3923 K and 5407 K for the halogen and xenon lamps, respectively. During diaphanoscopic illumination, a strong unwanted red shift was observed, resulting in 2199 K and 2675 K for the xenon and the halogen lamps, respectively. Regarding different applied pressures, the CCT did not differ considerably. (4) Conclusions: This red shift should be compensated for in the development of new illumination systems since surgeons are used to white light illumination, which also simplifies the identification of retinal structures.

Specific Targeting and Labeling of Colonic Polyps in CPC-APC Mice with Mucin 5AC Fluorescent Antibodies: A Model for Detection of Early Colon Cancer

Poor visualization of polyps can limit colorectal cancer screening. Fluorescent antibodies to mucin5AC (MUC5AC), a glycoprotein upregulated in adenomas and colorectal cancer, could improve screening colonoscopy polyp detection rate. Adenomatous polyposis coli flox mice with a Cdx2-Cre transgene (CPC-APC) develop colonic polyps that contain both dysplastic and malignant tissue. Mice received MUC5AC-IR800 or IRdye800 as a control IV and were sacrificed after 48 h for near-infrared imaging of their colons. A polyp-to-background ratio (PBR) was calculated for each polyp by dividing the mean fluorescence intensity of the polyp by the mean fluorescence intensity of the background tissue. The mean 25 μg PBR was 1.70 (±0.56); the mean 50 μg PBR was 2.64 (±0.97); the mean 100 μg PBR was 3.32 (±1.33); and the mean 150 μg PBR was 3.38 (±0.87). The mean PBR of the dye-only control was 2.22 (±1.02), significantly less than the 150 μg arm (p-value 0.008). The present study demonstrates the ability of fluorescent anti-MUC5AC antibodies to specifically target and label colonic polyps containing high-grade dysplasia and intramucosal adenocarcinoma in CPC-APC mice. This technology can potentially improve the detection rate and decrease the miss rate of advanced colonic neoplasia and early cancer at colonoscopy.

Precancerous Lesions of the Head and Neck Region and Their Stromal Aberrations: Piecemeal Data

Head and neck squamous cell carcinomas (HNSCCs) develop through a series of precancerous stages from a pool of potentially malignant disorders (PMDs). Although we understand the genetic changes that lead to HNSCC, our understanding of the role of the stroma in the progression from precancer to cancer is limited. The stroma is the primary battleground between the forces that prevent and promote cancer growth. Targeting the stroma has yielded promising cancer therapies. However, the stroma at the precancerous stage of HNSCCs is poorly defined, and we may miss opportunities for chemopreventive interventions. PMDs already exhibit many features of the HNSCC stroma, such as inflammation, neovascularization, and immune suppression. Still, they do not induce cancer-associated fibroblasts or destroy the basal lamina, the stroma's initial structure. Our review aims to summarize the current understanding of the transition from precancer to cancer stroma and how this knowledge can reveal opportunities and limitations for diagnostic, prognostic, and therapeutic decisions to benefit patients. We will discuss what may be needed to fulfill the promise of the precancerous stroma as a target to prevent progression to cancer.

Usefulness of third-generation narrow band imaging and texture and color enhancement imaging in improving visibility of superficial early gastric cancer: A study using color difference

OBJECTIVES

Overlooking early gastric cancer (EGC) during endoscopy is an issue to be resolved. Image-enhanced endoscopy is expected to improve EGC detection. This study investigated the usefulness of third-generation narrow band imaging (3G-NBI) and texture and color enhancement imaging (TXI) in improving the visibility of EGC using the color difference between EGC and its surrounding gastric mucosa.

METHODS

In this retrospective observational study, we examined 51 superficial EGCs that underwent endoscopic submucosal dissection and were observed by all three methods: 3G-NBI, TXI, and white light imaging (WLI). The primary endpoint was to compare the color difference of each method. For each EGC, we prepared one non-magnifying image for each method so that the location and size of the lesion in each image were the same. The L*a*b* color space was used to evaluate the color values. When the color values of the cancerous lesion and its surrounding mucosa were (L*c, a*c, b*c) and (L*s, a*s, b*s), respectively, the color difference was defined to be [(L*c-L*s)2+(a*c-a*s)2+(b*c-b*s)2]1/2.

RESULTS

The median color difference was 9.2 (interquartile range, 5.3-15.7) in WLI, 13.5 (interquartile range, 9.4-19.5) in 3G-NBI, and 15.3 (interquartile range, 9.1-22.1) in TXI. Statistically, the color difference was significantly larger in 3G-NBI than in WLI (p < 0.001) and TXI compared with WLI (p < 0.001). However, there was no significant difference between 3G-NBI and TXI (p = 0.330).

CONCLUSIONS

Regarding color difference, both 3G-NBI and TXI were estimated to be more useful than WLI in improving the visibility of superficial EGC.

Dysplastic Lesions of the Larynx

There have been many advancements in the clinical and histologic diagnosis of laryngeal dysplasia (LD), but diagnosis still necessitates invasive histologic evaluation. Furthermore, despite improved histologic identification of dysplastic lesions, the exact details of pathophysiologic progression and the risk of malignant transformation is still uncertain. These unknowns create a barrier to establishing an ideal grading and classification system, which prevents the establishment of a precise and consistent treatment paradigm. Identifying these gaps in knowledge serves to highlight where further studies are warranted, ideally focusing on a better understanding of the biological behavior of LD. This would ultimately allow for the creation of a reliable grading and classification system and for the formalization of management and treatment guidelines for LD.

Comparison Trial between I-SCAN-Optical Enhancement and Chromoendoscopy for Evaluating the Horizontal Margins of Gastric Epithelial Neoplasms

BACKGROUND/AIMS

Endoscopic submucosal dissection is a widely used treatment for gastric epithelial neoplasms. Accurate delineation of the horizontal margins is necessary for the complete resection of gastric epithelial neoplasms. Recently, image-enhanced endoscopy has been used to evaluate horizontal margins of gastric epithelial neoplasms. The aim of this study was to investigate whether I-SCAN-optical enhancement (I-SCAN-OE) is superior to chromoendoscopy in evaluating the horizontal margin of gastric epithelial neoplasms.

METHODS

This was a multicenter, prospective, and randomized trial. The participants were divided into two groups: I-SCAN-OE and chromoendoscopy. For both groups, we first evaluated the horizontal margins of early gastric cancer or high-grade dysplasia using white-light imaging, and then evaluated, the horizontal margins using I-SCAN-OE or chromoendoscopy. We devised a unique scoring method based on the pathological results obtained after endoscopic submucosal dissection to accurately evaluate the horizontal margins of gastric epithelial neoplasms. The delineation scores of both groups were compared, as were the ratios of positive/negative horizontal margins.

RESULTS

In total, 124 patients were evaluated for gastric epithelial neoplasms, of whom 112 were enrolled in the study. A total of 112 patients participated in the study, and 56 were assigned to each group (1:1). There was no statistically significant difference in the delineation scores between the groups (chromoendoscopy, 7.80±1.94; I-SCAN-OE, 8.23±2.24; p=0.342).

CONCLUSIONS

I-SCAN-OE did not show superiority over chromoendoscopy in delineating horizontal margins of gastric epithelial neoplasms.

Diagnosis and Management of Barrett's Esophagus

Barrett's esophagus is a metaplastic change of esophageal mucosa, which can be characterized by its salmon-colored lining and the presence of columnar epithelium with goblet cells. It is a well-established precancerous state of esophageal adenocarcinoma, a tumor with very poor survival rates, which incidence is rapidly growing. Despite numerous research, the debate about its diagnosis and management is still ongoing. This article aims to provide an overview of the current recommendations and new discoveries regarding the subject.

Contemporary advances in the endoscopic management of cholangiocarcinoma: a review of accomplished milestones and prospective opportunities

INTRODUCTION

Cholangiocarcinoma, a primary malignancy of epithelial cells of the bile ducts, has been shown to have increasing incidence rates globally. Many of the current advances aim to improve the accuracy of differentiation between benign biliary strictures and cholangiocarcinoma, which include endoscopic techniques, devices, image processing, and the use of genomic sequencing in acquired specimens.

AREAS COVERED

In this review, the authors explore the historical timeline of changes leading to modern management of cholangiocarcinoma, with special emphasis on endoscopic modalities and novel therapeutic interventions. The authors also expand on the strengths and shortcomings of endoscopic diagnostics and techniques in biliary drainage and finally discuss potential areas to focus for future research and development.

EXPERT OPINION

Despite the advances in diagnosis and management of cholangiocarcinoma, there remain multiple tasks that are still awaiting to be completed. Next-generation sequencing in the diagnosis of cholangiocarcinoma needs to be further tested, validated, and easily obtainable. Other innovative diagnostic modalities, such as the use of artificial intelligence in cholangioscopy, may provide an effective complementary modality to existing techniques. A consensus on biliary drainage needs to be defined and account for longevity and patient convenience.