Magnifying chromoendoscopy of the esophagus: in-vivo pathological diagnosis using an endocytoscopy system

Risk factors for lymph node metastasis in superficial esophageal squamous cell carcinoma

In this editorial, we comment on the article by Wang et al published in the recent issue of the World Journal of Gastroenterology in 2023. We focused on identifying risk factors for lymph node metastasis (LNM) in superficial esophageal squamous cell carcinoma (SESCC) patients and how to construct a simple and reliable clinical prediction model to assess the risk of LNM in SESCC patients, thereby helping to guide the selection of an appropriate treatment plan. The current standard treatment for SESCC is radical esophagectomy with lymph node dissection. However, esophagectomy is associated with considerable morbidity and mortality. Endoscopic resection (ER) offers a safer and less invasive alternative to surgical resection and can enable the patient's quality of life to be maintained while providing a satisfactory outcome. However, since ER is a localized treatment that does not allow for lymph node dissection, the risk of LNM in SESCC limits the effectiveness of ER. Understanding LNM status can aid in determining whether patients with SESCC can be cured by ER without the need for additional esophagectomy. Previous studies have shown that tumor size, macroscopic type of tumor, degree of differentiation, depth of tumor invasion, and lymphovascular invasion are factors associated with LNM in patients with SESCC. In addition, tumor budding is commonly associated with LNM, recurrence, and distant metastasis, but this topic has been less covered in previous studies. By comprehensively evaluating the above risk factors for LNM, useful evidence can be obtained for doctors to select appropriate treatments for SESCC patients.

Diagnostic Performance of a Novel Ultra-Thin Endoscopy under Narrow-Band Imaging for Superficial Squamous Cell Carcinoma of the Pharynx and Esophagus

This study aimed to evaluate the diagnostic utility of the ultra-thin endoscope (UTE) for superficial squamous cell carcinoma (SSCC) compared to magnifying endoscopy (ME) under narrow-band imaging. Participants underwent endoscopic examination, and images of pharyngeal and esophageal SCCs, as along with suspicious SSCC lesions, were collected using UTE and ME on the same day. Three image catalogs (UTE, ME-1, and ME-2) were created and reviewed by three expert endoscopists. ME-1 and ME-2 contained the same endoscopic images. The primary endpoint was the intra-observer agreement for diagnosing SCC. Eighty-six lesions (SCC = thirty-nine, non-SCC = forty-seven) in 43 participants were identified. The kappa values for the intra-observer agreement between UTE and ME-1 vs. the control (ME-1 vs. ME-2) were 0.74 vs. 0.84, 0.63 vs. 0.76, and 0.79 vs. 0.88, respectively. The accuracies for diagnosing SCC by UTE and ME-1 were 87.2% vs. 86.0%, 78.0% vs. 73,2%, and 75.6 vs. 82.6%, respectively, with no significant differences (p > 0.05). The rates of lesions that were diagnosed with confidence by UTE and ME-1 were 30.2% vs. 27.9%, 55.8% vs. 62.8%, and 58.1% vs. 55.8%, respectively. UTE demonstrates substantial diagnostic performance for SSCC in the pharynx and esophagus.

Superficial non-ampullary duodenal epithelial tumors now: endoscopic diagnosis and therapy

With the recent increase in the frequency of duodenal tumor detection, significant progress has been made in endoscopic diagnosis and treatment. Although the first guidelines were issued in Japan, patient treatment varies widely among institutions. There is a need for improving the quality of endoscopic diagnosis and more curative and safer treatments. Biopsy is the standard diagnostic method; however, the diagnostic accuracy of endoscopic biopsy is not so high. Therefore, the differentiation of superficial non-ampullary duodenal epithelial tumors from non-neoplastic lesions is being developed. The incidence of lymph node and distant metastases of duodenal epithelial tumors is extremely rare in intramucosal carcinomas, and they are considered good candidates for endoscopic treatment if the technical difficulties can be resolved. Adverse events associated with endoscopic treatment are greatly reduced at advanced facilities through novel resection and closure methods, and further improvements are expected in the future. Clarifying the risk of metastatic recurrence may lead to the development of more appropriate treatments and curative resection criteria.

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.

Novel endoscopic approaches using the endocytoscopy for the target biopsy in esophageal eosinophilia

BACKGROUND AND AIMS

Multiple biopsies are recommended for the diagnosis of eosinophilic esophagitis (EoE) because inflammatory changes are frequently patchy. Reports on EoE using endocytoscopy (ECS) are limited. This present study aimed to assess if diagnostic yield improves by adding ECS on conventional white light imaging (WLI) in patients with esophageal eosinophilia (EE).

METHODS

A total of 284 biopsy specimens from 71 patients with a known diagnosis of EE were enrolled and divided into the WLI group (156 specimens) or the ECS group (128 specimens). Four biopsies from 5 and 10 cm proximal to the esophagogastric junction were taken from each patient. In the ECS group, the biopsy was performed where bilobed nuclei were observed. The biopsy sensitivity for EE, eosinophil count of a single specimen and the biopsy sensitivity of each endoscopic finding were evaluated between both groups.

RESULTS

The sensitivity of a single biopsy specimen was higher in the ECS group than that of the WLI group (62.5 vs. 41.7%, P < 0.001). In addition, the median eosinophil count in the ECS group was significantly higher [19 vs. 6.5/high-power field (HPF), P < 0.001]. For each endoscopic finding, ECS-based biopsy had higher sensitivity than that of WLI in the diagnosis of edema (33.1 vs. 11.3%, P = 0.007) and linear furrows (75.8 vs. 52%, P = 0.005).

CONCLUSION

This study showed that adding ECS to WLI improved the biopsy sensitivity and eosinophil detection in patients with EE.

Endocytoscopic Observation of Esophageal Lesions: Our Own Experience and a Review of the Literature

This review outlines the process of the development of the endocytoscope (EC) with reference to previously reported studies including our own. The EC is an ultra-high-magnification endoscope capable of imaging at the cellular level. The esophagus is the most suitable site for EC observation because it is amenable to vital staining. The diagnosis of esophageal lesions using EC is based on nuclear density and nuclear abnormality, allowing biopsy histology to be omitted. The observation of nuclear abnormality requires a magnification of ×600 or higher using digital technology. Several staining methods have been proposed, but single staining with toluidine blue or methylene blue is most suitable because the contrast at the border of a cancerous area can be easily identified. A three-tier classification of esophageal lesions visualized by EC is proposed: Type 1 (non-cancerous), Type 2 (endocytoscopic borderline), and Type 3 (cancerous). Since characteristic EC images reflecting pathology can be obtained from non-cancerous esophageal lesions, a modified form of classification with four additional characteristic non-cancerous EC features has also been proposed. Recently, deep-learning AI for analysis of esophageal EC images has revealed that its diagnostic accuracy is comparable to that of expert pathologists.

AI analysis and modified type classification for endocytoscopic observation of esophageal lesions

Endocytoscopy (EC) facilitates real-time histological diagnosis of esophageal lesions in vivo. We developed a deep-learning artificial intelligence (AI) system for analysis of EC images and compared its diagnostic ability with that of an expert pathologist and nonexpert endoscopists. Our new AI was based on a vision transformer model (DeiT) and trained using 7983 EC images of the esophagus (2368 malignant and 5615 nonmalignant). The AI evaluated 114 randomly arranged EC pictures (33 ESCC and 81 nonmalignant lesions) from 38 consecutive cases. An expert pathologist and two nonexpert endoscopists also analyzed the same image set according to the modified type classification (adding four EC features of nonmalignant lesions to our previous classification). The area under the curve calculated from the receiver-operating characteristic curve for the AI analysis was 0.92. In per-image analysis, the overall accuracy of the AI, pathologist, and two endoscopists was 91.2%, 91.2%, 85.9%, and 83.3%, respectively. The kappa value between the pathologist and the AI, and between the two endoscopists and the AI showed moderate concordance; that between the pathologist and the two endoscopists showed poor concordance. In per-patient analysis, the overall accuracy of the AI, pathologist, and two endoscopists was 94.7%, 92.1%, 86.8%, and 89.5%, respectively. The modified type classification aided high overall diagnostic accuracy by the pathologist and nonexpert endoscopists. The diagnostic ability of the AI was equal or superior to that of the experienced pathologist. AI is expected to support endoscopists in diagnosing esophageal lesions based on EC images.

Convolutional neural network-based system for endocytoscopic diagnosis of early gastric cancer

Background

Endocytoscopy (ECS) aids early gastric cancer (EGC) diagnosis by visualization of cells. However, it is difficult for non-experts to accurately diagnose EGC using ECS. In this study, we developed and evaluated a convolutional neural network (CNN)-based system for ECS-aided EGC diagnosis.

Methods

We constructed a CNN based on a residual neural network with a training dataset comprising 906 images from 61 EGC cases and 717 images from 65 noncancerous gastric mucosa (NGM) cases. To evaluate diagnostic ability, we used an independent test dataset comprising 313 images from 39 EGC cases and 235 images from 33 NGM cases. The test dataset was further evaluated by three endoscopists, and their findings were compared with CNN-based results.

Results

The trained CNN required 7.0 s to analyze the test dataset. The area under the curve of the total ECS images was 0.93. The CNN produced 18 false positives from 7 NGM lesions and 74 false negatives from 28 EGC lesions. In the per-image analysis, the accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 83.2%, 76.4%, 92.3%, 93.0%, and 74.6%, respectively, with the CNN and 76.8%, 73.4%, 81.3%, 83.9%, and 69.6%, respectively, for the endoscopist-derived values. The CNN-based findings had significantly higher specificity than the findings determined by all endoscopists. In the per-lesion analysis, the accuracy, sensitivity, specificity, PPV, and NPV of the CNN-based findings were 86.1%, 82.1%, 90.9%, 91.4%, and 81.1%, respectively, and those of the results calculated by the endoscopists were 82.4%, 79.5%, 85.9%, 86.9%, and 78.0%, respectively.

Conclusions

Compared with three endoscopists, our CNN for ECS demonstrated higher specificity for EGC diagnosis. Using the CNN in ECS-based EGC diagnosis may improve the diagnostic performance of endoscopists.

Current status of endoscopic detection, characterization and staging of superficial esophageal squamous cell carcinoma

BACKGROUND

This review focuses on the current status of endoscopic detection, characterization and tumour category staging of oesophagealsquamous cell carcinoma.

DETECTION

The diagnostic yield of white-light imaging is limited and narrow-band imaging has demonstrated a better performance for detecting oesophageal cancer. Narrow-band imaging has also shown similar sensitivity and superior specificity to iodine staining.

CHARACTERIZATION

Accurate differentiation between cancerous and non-cancerous lesions can be achieved by magnifying narrow-band imaging or iodine staining with confirmation of a pink-colour sign. A per-patient analysis of a randomized study showed similar sensitivities, specificities and overall accuracies of magnifying narrow-band imaging and iodine staining of 82.2%, 95.1% and 91.2%, and 80.5%, 94.3% and 90.5%, respectively.

TUMOUR-STAGING

The diagnostic capability of endoscopic ultrasonography after conventional and narrow-band imaging in terms of tumour depth was evaluated in a multicentre prospective study. Endoscopic ultrasonography did not significantly improve the accuracy for distinguishing between mucosal or submucosal microinvasive cancer and deeper cancers from 72.9 to 74.0%, suggesting that additional endoscopic ultrasonography did not improve the diagnostic accuracy. In addition, endoscopic ultrasonography increased the incidence of overdiagnosis, defined as a diagnosis of cancer depth greater than the actual depth, by 6.6%. The risk of overdiagnosis by endoscopic ultrasonography was reconfirmed in two systematic reviews.

CONCLUSIONS

Narrow-band imaging is currently considered as the standard modality for the detection and characterization of oesophageal cancer. The risk of overdiagnosis should be considered when applying endoscopic ultrasonography for the evaluation of tumour invasion depth of superficial oesophageal squamous cell carcinoma.

The development and clinical application of microscopic endoscopy for in vivo optical biopsies: Endocytoscopy and confocal laser endomicroscopy

Endoscopies are crucial for detecting and diagnosing diseases in gastroenterology, pulmonology, urology, and other fields. To accurately diagnose diseases, sample biopsies are indispensable and are currently considered the gold standard. However, random 4-quadrant biopsies have sampling errors and time delays. To provide intraoperative real-time microscopic images of suspicious lesions, microscopic endoscopy for in vivo optical biopsy has been developed, including endocytoscopy and confocal laser endomicroscopy. This article reviews recent advances in technology and clinical applications, as well as their shortcomings and future directions.

Evaluation of Microvascular Patterns Alone Using Endocytoscopy with Narrow-Band Imaging for Diagnosing Gastric Cancer

INTRODUCTION

Although endocytoscopy (EC) with narrow-band imaging (NBI) is effective in diagnosing gastric cancer, no diagnostic system has been validated. We explored a specific diagnostic system for gastric cancer using EC with NBI.

METHODS

Equal numbers of images from cancerous and noncancerous areas (114 images each) were assessed by endoscopists with (development group: 33) and without (validation group: 28) specific training in magnifying endoscopy with NBI. Microvascular and microsurface patterns (MS) in each image were evaluated. Lesions were diagnosed as cancerous when patterns were deemed "irregular." The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of a diagnosis according to patterns on EC with NBI (microvascular pattern [MV] alone, MS alone, and both) were evaluated and compared between groups to determine the diagnostic performance.

RESULTS

In the development and validation groups, diagnoses based on the MV alone had significantly higher accuracy (91.7% vs. 76.3%, p < 0.0001 and 92.5% vs. 67.5%, p < 0.0001, respectively) and sensitivity (88.6% vs. 68.3%, p < 0.0001 and 89.5% vs. 38.6%, p < 0.0001, respectively) than those based on the MS alone. In both groups, there were no significant differences in diagnostic accuracy between using the MV alone and both patterns.

DISCUSSION/CONCLUSION

Evaluation of the MV alone is a simple and accurate diagnostic method for gastric cancer. This system could find widespread applications in clinical practice.

Ultra-magnifying Imaging of Thoracoscopic Biopsy Specimens Using Ex vivo Endocytoscopy in Three Patients with Mesothelioma

We performed endocytoscopy (ECS) for the ex vivo evaluation of mesothelioma in specimens biopsied during medical thoracoscopy in three patients. We evaluated 19 biopsy specimens based on the density of nuclei and irregularity in the nuclei shape using ECS and compared them with the histopathological findings. All 10 specimens considered malignant based on ECS were diagnosed as malignant based on histopathology. The nine specimens evaluated as non-malignant based on ECS consisted of six specimens diagnosed as malignant based on histopathology and three diagnosed as non-malignant based on histopathology. ECS was feasible and had some utility for ex vivo ultra-magnifying imaging of thoracoscopic biopsy specimens from patients with mesothelioma.

Endocytoscopy Is Useful for the Diagnosis of Superficial Nonampullary Duodenal Epithelial Tumors

INTRODUCTION

Endoscopic criteria for the diagnosis of superficial nonampullary duodenal epithelial tumors (SNADETs) are lacking. The aim of this study was to explore the usefulness of endocytoscopy (ECS) in the duodenum.

METHODS

A total of 77 ECS images stained by methylene blue and 58 images with double staining of methylene blue and crystal violet were obtained from 20 patients. Images were classified into 3 grades based on nuclear and villi atypia: EC A, B, and C. Diagnostic performance of ECS classification to predict histology and interobserver agreement was evaluated. The performance was compared between staining methods and ×520 or ×936 zoom.

RESULTS

With methylene blue staining, high rates of accuracy, sensitivity, specificity, and positive predictive value (PPV) over 90% were achieved for tumor and nontumor diagnosis as assessed by EC A versus EC B. High rates of accuracy, sensitivity, PPV, and negative predictive value over 90% were achieved for the differentiation between the diagnosis of the Vienna category 3 and 4/5 as assessed by EC B versus C. The accuracy rate of interpreting ECS images with ×936 zoom among 10 endoscopists was 82%, and the interobserver agreement rate was 0.803 (Kendall's coefficient of concordance). In the ×936 zoom group, methylene blue staining was significantly associated with higher accuracy rate (odds ratio 1.76 [1.06-2.92], p value 0.0297). No benefit was observed by double staining.

CONCLUSIONS

ECS diagnosis with methylene blue provides a high accuracy rate and good interobserver agreement to predict histology of SNADETs.

Diagnostic yield of fourth-generation endocytoscopy for esophageal squamous lesions using a modified endocytoscopic classification

OBJECTIVES

Endocytoscopy (EC) is an ultra-high magnification endoscopy designed to provide in vivo histologic assessment. This study aimed to evaluate the diagnostic yield of the newly developed fourth-generation EC for esophageal squamous lesions by using a modified EC classification.

METHODS

A total of 2548 EC images of 57 esophageal targeted areas between June 2015 and October 2017 were retrospectively collected. Two lesions with low-quality images were excluded. Only EC images were independently reviewed by two expert and two non-expert endoscopists. The lesions were classified according to a three-tier modified EC classification. We used a multilevel logistic regression to analyze the data.

RESULTS

The sensitivity and specificity of diagnosing non-squamous cell cancer (SCC) vs SCC were 82.5% and 83.0% by the experts; 90.1% and 75.0% by non-experts. The interobserver agreement among the four raters was good (kappa statistic 0.59). The diagnostic accuracy of experts and non-experts was similar (P = 0.16 for specificity and P = 0.20 for sensitivity). The sensitivity and specificity of EC for non-neoplasia vs neoplasia were 88.7% and 74.6% by experts; 90.3 and 52.1% by non-experts. The interobserver agreement among the four raters was moderate (kappa statistic 0.44). The specificity of experts was higher compared to non-experts, although the difference did not reach statistical significance (P = 0.08 for specificity and P = 0.93 for sensitivity).

CONCLUSIONS

Fourth-generation EC offers acceptable diagnostic accuracy and reliability in both experts and non-experts, especially when diagnosing SCC lesions.

Long-term outcomes of endoscopic submucosal dissection for superficial esophageal squamous cell carcinoma in Taiwan

Background

Endoscopic submucosal dissection (ESD) is gradually turning into the standard treatment for superficial esophageal squamous cell carcinoma (SESCC), however, the long-term outcomes have hardly ever been reported outside Japan.

Method

We consecutively recruited patients with SESCC who had received ESD treatment at E-Da Hospital. The demographics, pathological characteristics, and Lugol staining background pattern (type A or B: none or < 10 small Lugol-voiding lesions [LVLs]; type C or D: > 10 small or multiform LVLs) were collected, and then correlated to outcomes and survival.

Results

Total of 229 lesions were enrolled and the mean lesion size was 3.28 ± 1.69 (range 1–10) cm. 72% of the lesions had a type C-D Lugol staining background pattern. After ESD, the en bloc and R0 resection rates were 93.9% and 83.5%, respectively. Forty-nine subjects developed complications, including six (2.6%) with major bleeding, two (0.9%) with perforation, and 41 (17.9%) with strictures. Pathological staging showed that 19 cases had deep submucosal cancer invasion and subsequently received adjuvant therapies. During a mean follow-up period of 52.6 (range 3–146) months, 41 patients developed metachronous recurrence. The patients with a type C-D Lugol staining background pattern were associated with a higher risk of recurrence than those with few LVLs (log-rank P = 0.019). The 10-year survival rate was more than 90%, and only eight patients died of ESCC.

Conclusion

ESD has excellent long-term outcomes but a high risk of metachronous recurrence. The Lugol staining pattern over the background mucosa could offer the risk stratification of metachronous recurrence.

Clinical Efficacy of Endocytoscopy for Gastrointestinal Endoscopy

Endocytoscopy (EC) is a contact-type optical endoscope that allows in vivo cellular observation during gastrointestinal endoscopy and is now commercially available not only in Japan but also in Asian, European Union, and Middle Eastern countries. EC helps conduct a highly accurate pathological prediction without biopsy. Initially, EC was reported to be effective for esophageal diseases. Subsequently, its efficacy for stomach and colorectal diseases has been reported. In this narrative review, we searched for clinical studies that investigated the efficacy of EC. EC seems to accurately diagnose gastrointestinal diseases without biopsy. Most of the studies aimed to clarify the relationship between endocytoscopic findings of gastrointestinal neoplasia and pathological diagnosis. Some studies have investigated non-epithelial lesions or diseases, such as inflammatory bowel disease or infectious diseases. However, there are few high-level pieces of evidence, such as randomized trials; thus, further studies are needed.

Ultra-magnifying narrow-band imaging for endoscopic diagnosis of gastric intestinal metaplasia: a pilot image analysis study

Background and study aims  Narrow-band imaging (NBI) with or without magnification has recently been used for diagnosis of gastric intestinal metaplasia (GIM). Endocytoscopy is a newly developed endoscopic technique that enables ultra-high (500 ×) magnification of the digestive tract mucosa. This study aimed to analyze the ultra-magnifying NBI characteristics of GIM. Patients and methods  This was a retrospective observational study conducted in a cancer referral center. Patients who underwent ultra-magnifying NBI of the gastric mucosa using endocytoscopy were eligible. A soft black cap was used for non-contact observation. We compared the characteristic findings of GIM by ultra-magnifying NBI of metaplastic and non-metaplastic mucosae. A reference standard for GIM in this study was conventional magnifying NBI findings of GIM. Results  We obtained 28 images of metaplastic mucosa and 32 of non-metaplastic mucosa from 38 patients. Ultra-magnifying NBI revealed the cobblestone-like cellular structure in the marginal crypt epithelium of metaplastic and non-metaplastic mucosa. Diagnostic values (sensitivity, specificity, accuracy and kappa value [95 % confidence interval]) for the heterogeneous cellular structure and rough contour of the marginal crypt epithelium were 82 % (68 %-96 %), 94 % (85 %-100 %), 88 % (80 %-96 %), and 0.70, and 86 % (73 %-99 %), 94 % (85 %-100 %), 90 % (82 %-98 %), and 0.71, respectively. Conclusions  The characteristic ultrastructural features of GIM were identified by ultra-magnifying NBI, warranting validation of diagnostic value in a prospective study.

Diagnostic performance in gastric cancer is higher using endocytoscopy with narrow-band imaging than using magnifying endoscopy with narrow-band imaging

BACKGROUND

For diagnosing gastric cancer, differences in the diagnostic performance between endocytoscopy with narrow-band imaging and magnifying endoscopy with narrow-band imaging have not been reported. We aimed to clarify these differences by analyzing diagnoses made by endoscopists in Japan.

METHODS

This single-center retrospective cohort study used 106 cancerous and 106 non-cancerous images obtained via both modalities (total, 424 images) for diagnosis. Sixty-one endoscopists with varying experience levels from 45 institutions were included. Diagnostic accuracy, sensitivity, specificity, and positive and negative predictive values were evaluated to determine the diagnostic performance of each modality and compared using the Mann-Whitney U test.

RESULTS

Among all endoscopists, diagnostic accuracy, sensitivity, positive predictive value, and negative predictive value were higher with endocytoscopy with narrow-band imaging than with magnifying endoscopy with narrow-band imaging (percentage [95% confidence interval]: 78.8% [76.4-83.0%] versus 72.2% [69.3-73.6%], p < 0.0001; 82.1% [78.3-85.9%] versus 64.2% [60.4-69.8%], p < 0.0001; 88.7% [82.6-90.7%] versus 78.5% [75.4-85.1%], p = 0.0023; 79.0% [75.3-80.5%] versus 68.5% [66.4-71.6%], p < 0.0001, respectively). In the magnifying endoscopy with narrow-band imaging-trained group, these values were also higher with endocytoscopy with narrow-band imaging than with magnifying endoscopy with narrow-band imaging (p < 0.0001, p = 0.0001, p = 0.0143, and p < 0.0001, respectively). Diagnostic accuracy, sensitivity, and negative predictive value were higher with endocytoscopy with narrow-band imaging than with magnifying endoscopy with narrow-band imaging in the magnifying endoscopy with narrow-band imaging-untrained group (p = 0.0041, p = 0.0049, and p = 0.0098, respectively).

CONCLUSIONS

Diagnostic performance was higher using endocytoscopy with narrow-band imaging than using magnifying endoscopy with narrow-band imaging. Our results may help change the technique used to diagnose gastric cancer.

Multicenter prospective in vivo study of an endocytoscope system (ECS) for superficial esophageal cancer

BACKGROUND

Endocytoscope systems (ECS) can visualize cellular nuclei of the mucosa of the gastrointestinal tract and are predicted to provide real-time microscopic diagnosis. However, their practical diagnostic performance remains unclear. Therefore, we conducted a multicenter prospective study to evaluate the visualization of superficial esophageal neoplasm in vivo using an ECS, and its diagnostic capability.

METHODS

The study target was histologically confirmed squamous cell carcinoma (SCC) and high-grade intraepithelial neoplasia (HGIN). An integrated ECS was used to obtain ECS images. In each patient, three ECS images of cancerous and corresponding noncancerous regions were selected for evaluation. A pathological review board of five certified pathologists made the final diagnosis of the images. The primary endpoint was the sensitivity of ECS diagnosis by pathologists.

RESULTS

ECS images of 68 patients were assessed: 42 lesions were mucosal SCC, 13 were submucosal SCC, and 13 were HGIN. The rate of assessable images was 96% (95% CI 87.6-99.1). The sensitivity of ECS diagnosis by pathologists was 88% (95% CI 77.2-94.5).

CONCLUSIONS

ECS can provide high-quality images of cancerous lesions and a high diagnostic accuracy by pathologists, and could be useful for real-time endoscopic histological diagnosis of SCC and HGIN.

TRIAL REGISTRATION

The UMIN Clinical Trials Registry Identification Number: 000004218.

Artificial intelligence assisted endocytoscopy: A novel eye in endoscopy

Over the past few years, emerging new approaches in endoscopic imaging technologies facilitate a high-quality assessment of lesions found in the gastrointestinal (GI) tract. Endocytoscopy (EC), as a novel tool in endoscopy, aids the more accurate evaluation of superficial mucosal surface. This review article aims to represent the most relevant information related to the latest EC technology and its clinical application in the lower GI tract diagnostic. We discuss EC-computer-aided diagnosis capability to differentiate between non-neoplastic and neoplastic lesion that offers a closer look to in-vivo assessment and diagnosis of cancerous tissue. Nevertheless, artificial-assisted EC diagnostics could also be employed with benefits in patients with inflammatory bowel disease (IBD) by accurately highlighting the presence of mucosal injury. In our review we included those studies comprising data about colonoscopy with narrow banding imaging and computer-aided diagnosis, as well as EC. Last but not least, artificial-assisted EC facilitates in-vivo diagnosis of the lower GI tract and may, in the future, remodel the field of in-vivo endoscopic diagnosis of colorectal lesions, representing another step towards the so-called optical biopsy.

Artificial intelligence technique in detection of early esophageal cancer

Due to the rapid progression and poor prognosis of esophageal cancer (EC), the early detection and diagnosis of early EC are of great value for the prognosis improvement of patients. However, the endoscopic detection of early EC, especially Barrett's dysplasia or squamous epithelial dysplasia, is difficult. Therefore, the requirement for more efficient methods of detection and characterization of early EC has led to intensive research in the field of artificial intelligence (AI). Deep learning (DL) has brought about breakthroughs in processing images, videos, and other aspects, whereas convolutional neural networks (CNNs) have shone lights on detection of endoscopic images and videos. Many studies on CNNs in endoscopic analysis of early EC demonstrate excellent performance including sensitivity and specificity and progress gradually from in vitro image analysis for classification to real-time detection of early esophageal neoplasia. When AI technique comes to the pathological diagnosis, borderline lesions that are difficult to determine may become easier than before. In gene diagnosis, due to the lack of tissue specificity of gene diagnostic markers, they can only be used as supplementary measures at present. In predicting the risk of cancer, there is still a lack of prospective clinical research to confirm the accuracy of the risk stratification model.

The Role of Modern Radiotherapy Technology in the Treatment of Esophageal Cancer

Radiation therapy (RT) has improved patient outcomes, but treatment-related complication rates remain high. In the conventional 2-dimensional and 3-dimensional conformal RT (3D-CRT) era, there was little room for toxicity reduction because of the need to balance the estimated toxicity to organs at risk (OARs), derived from dose-volume histogram data for organs including the lung, heart, spinal cord, and liver, with the planning target volume (PTV) dose. Intensity-modulated RT (IMRT) is an advanced form of conformal RT that utilizes computer-controlled linear accelerators to deliver precise radiation doses to the PTV. The dosimetric advantages of IMRT enable better sparing of normal tissues and OARs than is possible with 3D-CRT. A major breakthrough in the treatment of esophageal cancer (EC), whether early or locally advanced, is the use of proton beam therapy (PBT). Protons deposit their highest dose of radiation at the tumor, while leaving none behind; the resulting effective dose reduction to healthy tissues and OARs considerably reduces acute and delayed RT-related toxicity. In recent studies, PBT has been found to alleviate severe lymphopenia resulting from combined chemo-radiation, opening up the possibility of reducing immune suppression, which might be associated with a poor prognosis in cases of locally advanced EC.

Utilizing artificial intelligence in endoscopy: a clinician's guide

INTRODUCTION

Artificial intelligence (AI) that surpasses human ability in image recognition is expected to be applied in the field of gastrointestinal endoscopes. Accordingly, its research and development (R &D) is being actively conducted. With the development of endoscopic diagnosis, there is a shortage of specialists who can perform high-precision endoscopy. We will examine whether AI with excellent image recognition ability can overcome this problem.

AREAS COVERED

Since 2016, papers on artificial intelligence using convolutional neural network (CNN in other word Deep Learning) have been published. CNN is generally capable of more accurate detection and classification than conventional machine learning. This is a review of papers using CNN in the gastrointestinal endoscopy area, along with the reasons why AI is required in clinical practice. We divided this review into four parts: stomach, esophagus, large intestine, and capsule endoscope (small intestine).

EXPERT OPINION

Potential applications for the AI include colorectal polyp detection and differentiation, gastric and esophageal cancer detection, and lesion detection in capsule endoscopy. The accuracy of endoscopic diagnosis will increase if the AI and endoscopist perform the endoscopy together.

The Impact of Artificial Intelligence in the Endoscopic Assessment of Premalignant and Malignant Esophageal Lesions: Present and Future

In the gastroenterology field, the impact of artificial intelligence was investigated for the purposes of diagnostics, risk stratification of patients, improvement in quality of endoscopic procedures and early detection of neoplastic diseases, implementation of the best treatment strategy, and optimization of patient prognosis. Computer-assisted diagnostic systems to evaluate upper endoscopy images have recently emerged as a supporting tool in endoscopy due to the risks of misdiagnosis related to standard endoscopy and different expertise levels of endoscopists, time-consuming procedures, lack of availability of advanced procedures, increasing workloads, and development of endoscopic mass screening programs. Recent research has tended toward computerized, automatic, and real-time detection of lesions, which are approaches that offer utility in daily practice. Despite promising results, certain studies might overexaggerate the diagnostic accuracy of artificial systems, and several limitations remain to be overcome in the future. Therefore, additional multicenter randomized trials and the development of existent database platforms are needed to certify clinical implementation. This paper presents an overview of the literature and the current knowledge of the usefulness of different types of machine learning systems in the assessment of premalignant and malignant esophageal lesions via conventional and advanced endoscopic procedures. This study makes a presentation of the artificial intelligence terminology and refers also to the most prominent recent research on computer-assisted diagnosis of neoplasia on Barrett’s esophagus and early esophageal squamous cell carcinoma, and prediction of invasion depth in esophageal neoplasms. Furthermore, this review highlights the main directions of future doctor–computer collaborations in which machines are expected to improve the quality of medical action and routine clinical workflow, thus reducing the burden on physicians.

Endocytoscopic Observation of Non-Ampullary Mucosal Duodenal Cancer

Our previous study of duodenal adenoma using an endocytoscopy system (ECS) demonstrated that disappearance of goblet cells and spindle-shaped nuclei with loss of polarity were characteristic features. In addition, round duct openings and finger-like projections were observed in tubular adenoma and villous adenoma, respectively. Here, we retrospectively investigated six cases of histologically proven sporadic non-ampullary mucosal duodenal cancer (NAMDC) using ECS. Immunohistochemistry for CD10, MUC2, MUC5AC, and MUC6 was employed to determine the mucin phenotype in addition to conventional HE histology. Immunohistochemistry revealed one case involving the duodenal bulb that was considered to be the mixed type. The other five cases, located in the second or third portion, were considered to be the intestinal type. Vital staining of the mixed-type case was considered insufficient for ECS observation because of surface mucus. However, all five cases of intestinal-type duodenal cancer demonstrated a villous structure, disappearance of goblet cells and enlarged nuclei with loss of polarity. Tubular structures were admixed in four of those cases. Four cases demonstrated oval-shaped nuclei, and one case had spindle-shaped nuclei. Cases showing spindle-shaped nuclei in most of the lesion were diagnosed histologically as cancer in adenoma where the adenomatous component of the tumor was dominant. Oval-shaped nuclei and nuclear enlargement are the characteristic features of NAMDC revealed by ECS and are included among the histological criteria used for diagnosis. ECS offers the potential to perform real-time histological diagnosis of NAMDC in vivo.

Diagnosis using deep-learning artificial intelligence based on the endocytoscopic observation of the esophagus

BACKGROUND AND AIMS

The endocytoscopic system (ECS) helps in virtual realization of histology and can aid in confirming histological diagnosis in vivo. We propose replacing biopsy-based histology for esophageal squamous cell carcinoma (ESCC) by using the ECS. We applied deep-learning artificial intelligence (AI) to analyse ECS images of the esophagus to determine whether AI can support endoscopists for the replacement of biopsy-based histology.

METHODS

A convolutional neural network-based AI was constructed based on GoogLeNet and trained using 4715 ECS images of the esophagus (1141 malignant and 3574 non-malignant images). To evaluate the diagnostic accuracy of the AI, an independent test set of 1520 ECS images, collected from 55 consecutive patients (27 ESCCs and 28 benign esophageal lesions) were examined.

RESULTS

On the basis of the receiver-operating characteristic curve analysis, the areas under the curve of the total images, higher magnification pictures, and lower magnification pictures were 0.85, 0.90, and 0.72, respectively. The AI correctly diagnosed 25 of the 27 ESCC cases, with an overall sensitivity of 92.6%. Twenty-five of the 28 non-cancerous lesions were diagnosed as non-malignant, with a specificity of 89.3% and an overall accuracy of 90.9%. Two cases of malignant lesions, misdiagnosed as non-malignant by the AI, were correctly diagnosed as malignant by the endoscopist. Among the 3 cases of non-cancerous lesions diagnosed as malignant by the AI, 2 were of radiation-related esophagitis and one was of gastroesophageal reflux disease.

CONCLUSION

AI is expected to support endoscopists in diagnosing ESCC based on ECS images without biopsy-based histological reference.

Advanced Imaging for Barrett's Esophagus and Early Neoplasia: Surface and Subsurface Imaging for Diagnosis and Management

PURPOSE OF REVIEW

Esophageal adenocarcinoma bears one of the fastest rising incidence of any cancers and generally arises in the setting of gastroesophageal reflux and Barrett's esophagus. However, early detection of neoplasia can be challenging since most patients are asymptomatic until they progress to more advanced and less curable stages, and early dysplastic lesions can be small, multifocal, and difficult to detect. Clearly, new imaging tools are needed in light of sampling error associated with random biopsies, the current standard of practice.

RECENT FINDINGS

Advances in endoscopic imaging including virtual chromoendoscopy, confocal laser endomicroscopy, and subsurface imaging with optical coherence tomography have ushered in a new era for detecting subtle neoplastic lesions. Moreover, in light of esophagus-sparing treatments for neoplastic lesions, such tools are likely to guide ablation and follow-up management. While there is no ideal single imaging modality to facilitate improved detection, staging, ablation, and follow-up of patients with dysplastic Barrett's esophagus, new advances in available technology, the potential for multimodal imaging, and the use of computer-aided diagnosis and biomarkers all hold great promise for improving detection and treatment.

Comparison of endoscopic submucosal dissection and surgery for superficial esophageal squamous cell carcinoma: a propensity score-matched analysis

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) has been widely accepted for treating superficial esophageal squamous cell carcinoma (SESCC). However, long-term outcomes of ESD and esophagectomy for SESCC have not been compared. We compared the clinical outcomes of ESD and esophagectomy in a matched cohort.

METHODS

Patients who underwent ESD and esophagectomy for SESCC were included. We selected SESCCs without obvious submucosal invasion from the surgical database by reviewing endoscopic images. To minimize the effect of selection bias, propensity score matching was performed. Overall survival (OS), disease-specific survival (DSS), recurrence-free survival (RFS), and metachronous RFS were compared between the 2 groups. Adverse event rates were also compared.

RESULTS

In a matched cohort of 120 pairs, OS, DSS, and RFS were comparable between the 2 groups. The 5-year OS, DSS, and RFS rates were 93.9% versus 91.2%, 100% versus 97.4%, and 92.8% versus 95.3% for the ESD and esophagectomy groups, respectively. The metachronous RFS was worse in the ESD group than in the esophagectomy group (P = .004). The 5-year metachronous RFS rates were 90.3% versus 100% for the ESD and esophagectomy groups, respectively. The esophagectomy group showed a higher overall adverse event rate than the ESD group (55.5% vs 18.5%, P < .0001). In each subgroup of mucosal and submucosal cancer, OS, DSS, and RFS were also comparable between the 2 groups.

CONCLUSIONS

ESD provides long-term outcomes comparable with esophagectomy in patients with SESCC without endoscopic evidence of obvious submucosal invasion. ESD should be considered as the first-line treatment for these patients.

Screening for esophageal squamous cell carcinoma: recent advances

Esophageal squamous cell carcinoma (ESCC) is the most common type of esophageal cancer worldwide, with a high mortality due to advanced stage at diagnosis. Although most common in an area known as the Asian Esophageal Cancer Belt, which extends from the Caspian Sea to northern China, and in parts of Africa, high-risk populations also exist elsewhere in the world. Screening for ESCC has been practiced in a few geographic areas and high-risk populations, with varying levels of success. Esophageal squamous dysplasia is recognized as the precursor lesion for ESCC. Endoscopic screening for ESCC/esophageal squamous dysplasia is expensive and not sufficiently available in many high-risk regions. Recent advances in non-endoscopic screening enhanced by biomarker-based disease detection have raised the prospect of improved accuracy and availability of screening for esophageal squamous dysplasia and early stage ESCC. Development of a cost-effective, accurate, and well-tolerated screening test, if applied in endemic areas and high-risk populations, has the potential to reduce mortality from this deadly disease worldwide. In this review, we summarize recent developments in endoscopic and non-endoscopic screening modalities.

Predicting lymph node metastasis for endoscopic resection of superficial esophageal squamous cell carcinoma

OBJECTIVE

The aims of this study were to identify risk factors for lymph node metastasis and develop a reliable risk stratification system.

METHODS

Between May 2001 and December 2015, 262 patients who underwent endoscopic resection or surgery for superficial esophageal squamous cell carcinoma were enrolled. We evaluated possible predictive factors for lymph node metastasis: age, gender, tumor length, tumor area, circumferential spread, tumor location, gross appearance, depth of invasion, tumor differentiation, and lymphovascular invasion.

RESULTS

The incidence of lymph node metastasis was 14.5% (38/262). In multivariate analysis, tumor size (>15 mm), depth of invasion (submucosal invasion), and lymphovascular invasion were significantly associated with lymph node metastasis. These factors were included in the risk stratification system and assigned scores; the total risk stratification system score was 0 to 6. The area under the receiver operating characteristic curve for predicting lymph node metastasis was 0.869 (95% confidence interval, 0.813-0.926). The high-risk group (risk stratification system score ≥3) exhibited a significantly higher risk of lymph node metastasis than the low-risk group (score <3) (26.5% vs 1.6%). There was no lymph node metastasis in patients with a risk stratification system of 0. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the risk stratification system were 94.7%, 55.4%, 26.5%, 98.4%, and 61.1%, respectively.

CONCLUSIONS

We developed a risk stratification system that should facilitate the identification of patients with a high or low risk of lymph node metastasis. This may aid the precise selection of patients who can undergo endoscopic resection.

Endoscopic submucosal dissection under general anesthesia for superficial esophageal squamous cell carcinoma is associated with better clinical outcomes

Background

Endoscopic submucosal dissection (ESD) has been widely accepted for treating superficial esophageal squamous cell carcinoma (SESCC). The aim of this study was to evaluate the efficacy and safety of ESD for SESCC and the effect of different sedation methods on their clinical outcomes.

Methods

We retrospectively analyzed a total of 169 patients (175 lesions) who underwent ESD for SESCC at Samsung Medical Center, Seoul, South Korea. Short-term and long-term clinical outcomes were evaluated and compared according to the sedation method (conscious sedation [CS] vs general anesthesia [GA]).

Results

En bloc resection, complete resection, and curative resection (CuR) were achieved in 93.7, 74.9, and 58.9% of cancers, respectively. Perforation and stricture occurred in 8.0 and 12.0% of lesions, respectively. During a mean follow-up period of 33.7 months for survival, 3 (3.0%) patients died without evidence of recurrence after achieving CuR. During a mean follow-up period of 32.5 months for recurrence, 1 (1.0%) patient experienced lymph node metastasis. Synchronous and metachronous cancer were found in 1.0% and in 3.0% of patients, respectively. Multivariate analysis revealed that GA was associated with a higher complete resection rate and a lower perforation rate as compared to CS (odds ratio 3.401, 95% confidence interval 1.317–8.785, P = 0.011 and odds ratio 0.067, 95% confidence interval 0.006–0.775, P = 0.030, respectively).

Conclusions

ESD is an oncologically effective treatment modality for SESCC, particularly when CuR is achieved. Applying GA for esophageal ESD could improve the clinical outcomes of ESD in patients with SESCC.

[Endoscopic Treatment for Esophageal Cancer]

Esophageal cancer incidence rate per 100,000 is 4.7 in 2013, which accounts for 1.1% of the total cancer incidence in Korea. Superficial esophageal squamous cell carcinoma is frequently detected in persons undergoing upper endoscopy for gastrointestinal symptoms or for gastric cancer screening. Esophagectomy with lymph node dissection is the standard treatment for esophageal cancer. However, given the considerable morbidity and mortality of esophagectomy, endoscopic resection has become the standard of care for most cases of superficial esophageal squamous cell carcinoma without metastasis. In addition, endoscopic submucosal dissection has increased the cure rate, even when the tumor is large, compared to endoscopic mucosal resection. Thus, endoscopic submucosal dissection is the treatment of choice for superficial esophageal squamous cell carcinoma with a negligible risk of lymph node metastasis. Endoscopic resection is usually associated with a low risk of morbidity and no mortality, and has also shown favorable long-term outcomes. However, the long-term risk of metastasis remains after endoscopic resection, which varies according to the characteristics of tumor. This review describes the indication and outcomes of endoscopic resection, complications of endoscopic resection, and management after treatment.

Endoscopic prediction model for differentiating upper submucosal invasion (< 200 μm) and beyond in superficial esophageal squamous cell carcinoma

Esophageal endoscopic submucosal dissection (ESD) can be attempted in superficial esophageal squamous cell carcinoma (SESCC) invading the upper submucosal layer (SM1: invasion < 200 μm). This study aimed to determine endoscopic predictive features associated with beyond SM1 invasion in SESCC and establish a predictive model using the identified features. This study retrospectively analyzed 203 esophageal ESD for SESCC. Endoscopic images were reviewed by two endoscopists. Tumors were evaluated for main shape, sizes, and surface characteristics. The association between each endoscopic feature and beyond SM1 invasion was evaluated. Using the significant endoscopic features in multivariate analysis, a predictive model for beyond SM1 invasion in SESCC was established. Among 203 SESCCs, 40 (19.7%) invaded beyond SM1. Multivariate analysis revealed that surface nodularity [odds ratio (OR) 41.340, 95% confidence interval (CI) 8.492–201.252, p < 0.001], surface granularity (OR 18.682, 95% CI 4.818–72.440, p < 0.001), surface unevenness, (OR 4.107, 95% CI 1.160–14.543, p = 0.029), deep depression (OR 27.490, 95% CI 2.897–260.853, p = 0.004), and thick notch (OR 41.701, 95% CI 6.646–261.672, p < 0.001) were independently associated with beyond SM1 invasion. An established model showed an area under the curve of 0.921 with 95% CI 0.881–0.960. The best cut-off value showed the following: sensitivity, 0.85; specificity, 0.83; positive predictive value, 0.55; and negative predictive value, 0.96. In conclusion, endoscopic features can predict beyond SM1 invasion in SESCC. Our prediction model is potentially useful for screening ESD candidates in SESCC.

Treatment outcomes of extended-field radiation therapy for thoracic superficial esophageal cancer

Purpose

To evaluate the efficacy and safety of extended-field radiation therapy for patients with thoracic superficial esophageal cancer (SEC).

Materials and Methods

From May 2007 to October 2016, a total of 24 patients with thoracic SEC (T1a and T1b) who underwent definitive radiotherapy and were analyzed retrospectively. The median total radiotherapy dose was 64 Gy (range, 54 to 66 Gy) in conventional fractionation. All 24 patients received radiotherapy to whole thoracic esophagus and 23 patients received elective nodal irradiation. The supraclavicular lymph nodes, the celiac lymph nodes, and both of those nodal areas were included in 11, 3, and 9 patients, respectively.

Results

The median follow-up duration was 28.7 months (range 7.9 to 108.0 months). The 3-year overall survival, local control, and progression-free survival rates were 95.2%, 89.7%, and 78.7%, respectively. There were 5 patients (20.8%) with progression of disease, 2 local failures (8.3%) and 3 (12.5%) regional failures. Three patients also experienced distant metastasis and had died of disease progression. There were no treatment-related toxicities of grade 3 or higher.

Conclusion

Definitive extended-field radiotherapy for thoracic SEC showed durable disease control rates in medically inoperable and endoscopically unfit patients. Even extended-field radiotherapy with elective nodal irradiation was safe without grade 3 or 4 toxicities.

Classification of nuclear morphology in endocytoscopy of colorectal neoplasms

BACKGROUND AND AIMS

We investigated endocytoscopy (EC) findings that were considered risk factors for colorectal neoplasms and determined whether they could be used as new indices to identify carcinomas with massive submucosal invasion (SM-m) or worse outcomes.

METHODS

We performed a multivariate analysis of 8 factors on EC images to determine whether they were associated with SM-m or worse. Based on the results, we divided the EC3a category of the EC classification into low grade or high grade and investigated the diagnostic accuracy of this subclassification. In addition, we compared the diagnostic ability of EC for SM-m with that of other modalities (narrow-band imaging and pit pattern).

RESULTS

The multivariate analysis indicated that unclear glandular lumens (ULs), high degree of nuclear enlargement (HNE), and multilayered nuclei (MNs) were the most useful factors for the diagnosis of SM-m or worse. The odds ratios for these factors were 12.47, 12.29, and 10.48, respectively (P < .001). The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and positive likelihood ratio for the diagnostic accuracy of the EC3a subclassification were 88.9%, 91.3%, 75.0%, 96.6%, 90.8%, and 10.2, respectively (P < .001). The sensitivity, negative predictive value, and accuracy of EC were significantly higher than those of narrow-band imaging and pit pattern.

CONCLUSIONS

From the EC findings, the presence of ULs, HNE, and MNs are important risk factors for SM-m or worse outcomes. Furthermore, the EC3a subclassification taking these findings into consideration could be effective for the diagnosis of SM-m or worse. (Clinical trial registration number: UMIN 000014906.).

Ten-year experience of esophageal endoscopic submucosal dissection of superficial esophageal neoplasms in a single center

BACKGROUND/AIMS

Endoscopic submucosal dissection (ESD) of a superficial esophageal neoplasm (SEN) is a technically difficult procedure. We investigated the clinical outcomes of ESD to determine its feasibility and effectiveness for the treatment of SEN.

METHODS

Patients who underwent ESD for SEN between August 2005 and June 2014 were eligible for this study. The clinical features of patients and tumors, histopathologic characteristics, adverse events, results of endoscopic resection, and survival were investigated.

RESULTS

ESD was performed in 225 patients with 261 lesions, including 70 cases (26.8%) of dysplasias and 191 cases (73.2%) of squamous cell carcinomas. The median age was 65 years (range, 44 to 86), and the male to female ratio was 21.5:1. Median tumor size was 37 mm (range, 5 to 85) and median procedure time was 45 minutes (range, 9 to 160). En bloc resection was performed in 245 of 261 lesions (93.9%), with complete resection in 234 lesions (89.7%) and curative resection in 201 lesions (77.0%). Adverse events occurred in 33 cases (12.6%), including bleeding (1.5%), perforation (4.6%), and stricture (6.5%). During a median follow-up period of 35.0 months (interquartile range, 18 to 62), none of the patients showed local recurrence. The 5-year overall and disease-specific survival rates were 89.7% and 100%, respectively.

CONCLUSIONS

ESD is a feasible and effective procedure for the treatment of SEN based on our 10-year experience, which showed favorable outcomes.

Clinical Outcomes of Endoscopic Submucosal Dissection for Early Esophageal Squamous Cell Neoplasms: A Retrospective Single-Center Study in China

Aims. To retrospectively analyze the clinical outcomes for a large number of endoscopic submucosal dissections (ESDs) in early esophageal squamous cell neoplasms (ESCNs) at the First Affiliated Hospital of Nanjing Medical University. Patients and Methods. From January 2010 to February 2014, 296 patients (mean age 61.4 years, range 31–85 years; 202 men) with 307 early ESCNs (79 intramucosal invasive esophageal squamous cell carcinomas (ESCCs) and 228 high-grade intraepithelial neoplasia (HGIN) cases) were included from a total of 519 consecutive patients who were treated by esophageal ESD at our hospital. The primary end points of the study were rates of en bloc resection and complete resection. Secondary end points were complications, residual and recurrence rates, and mortality during follow-up. Results. The en bloc resection rate and complete resection rate were 93.5% and 78.2%, respectively. Complications included strictures (8.4%), perforations (1.0%), and bleedings (0.7%). Twenty-seven (9.1%) patients experienced residual and 18 (6.1%) patients experienced recurrence during a mean follow-up period of 30 months. Thirteen patients died from causes unrelated to ESCC, and no cancer-related death was observed. Conclusions. Our study showed that ESD is a successful and relatively safe treatment for intramucosal invasive ESCC and HGIN, fulfilling the criteria of lymph node negative tumors. This should encourage clinicians to select ESD performed by experienced operators as a potential or even preferred treatment option for lesions amenable to endoscopic treatment.

Light and sound - emerging imaging techniques for inflammatory bowel disease

Patients with inflammatory bowel disease are known to have a high demand of recurrent evaluation for therapy and disease activity. Further, the risk of developing cancer during the disease progression is increasing from year to year. New, mostly non-radiant, quick to perform and quantitative methods are challenging, conventional endoscopy with biopsy as gold standard. Especially, new physical imaging approaches utilizing light and sound waves have facilitated the development of advanced functional and molecular modalities. Besides these advantages they hold the promise to predict personalized therapeutic responses and to spare frequent invasive procedures. Within this article we highlight their potential for initial diagnosis, assessment of disease activity and surveillance of cancer development in established techniques and recent advances such as wide-view full-spectrum endoscopy, chromoendoscopy, autofluorescence endoscopy, endocytoscopy, confocal laser endoscopy, multiphoton endoscopy, molecular imaging endoscopy, B-mode and Doppler ultrasound, contrast-enhanced ultrasound, ultrasound molecular imaging, and elastography.

Diagnosis of sessile serrated adenomas/polyps using endocytoscopy (with videos)

Sessile serrated adenomas/polyps (SSA/P) are considered to be precursors of colorectal cancers. They therefore need to be distinguished from hyperplastic polyps, and should be treated similarly to adenomas. Various endoscopic classifications for discriminating SSA/P have recently been proposed and validated, including the 'Type II-O' pit pattern in magnifying chromoendoscopy and the 'varicose microvascular vessel' in narrow-band imaging. However, there is currently no diagnostic consensus on the endoscopic appearance of SSA/P. Endocytoscopy (EC) is an emerging modality with diagnostic potential for SSA/P. EC is a type of a contact light microscopy, which allows in vivo visualization of cells and nuclei facilitating precise, real-time pathological prediction. SSA/P show oval gland lumens with small round nuclei in EC, indirectly reflecting the pathological features. EC has shown a sensitivity of 83.3% and a specificity of 97.8% for the diagnosis of SSA/P. EC is also a promising tool for the diagnosis of SSA/P with cytological dysplasia because of its ability to detect morphological changes in nuclei, which is the most important factor determining the presence of dysplasia in the lesion. However, clinical data validating the usefulness of EC are lacking, and further studies are required.

Endoscopic submucosal dissection for treatment of early esophageal cancer and precancerous lesions

Esophageal cancer is the eighth most common form of cancer worldwide. Advances in endoscopic therapy have resulted in dramatic changes in the way early esophageal cancer and precancerous lesions are managed. Endoscopic submucosal dissection (ESD) is a newly developed resection technique that is able to achieve a high R0 resection rate and a low local recurrence rate. Techniques of ESD have become established as standard methods of endoscopic resection. This review addresses some of the recent developments in the field of ESD for early esophageal cancer and precancerous lesions.

Advanced endoscopic imaging for early gastric cancer

Considerable numbers of early gastric cancers can be missed or misdiagnosed with conventional white light imaging endoscopy (WLI), thus advanced endoscopic imaging modalities have been applied to overcome the issue. High definition endoscopy can improve diagnostic accuracy, but still misses 20-25% of early gastric cancer. Magnifying endoscopy combined with narrow band imaging (NBI) allows for very high accuracy, with sensitivity and specificity of over 95%. The algorithm for magnifying endoscopy diagnosis of gastric cancer is composed of 1) presence of demarcation line, and 2) presence of irregular microsurface and/or microvascular pattern. Ultra-high magnification of 400 times with endocytoscopy (ECS) can produce images reflecting structural and cellular atypia. Using high grade ECS atypia as the diagnostic criteria for gastric cancer, ECS achieves a high diagnostic accuracy (86% of sensitivity, 100% of specificity) although approximately 10% of target lesions are not assessable because of poor dye staining.

Combination of miRNA and RNA functions as potential biomarkers for gastric cancer

Gastric cancer (GC) is the second leading cause of cancer-related death in the world. The optimal treatment regimens for GC depend on tumor stage, histopathological subtype, and other factors. The detection of tumor biomarkers is a quick way to get information of the tumor state. In this study, new biomarkers are detected for GC diagnostic and prognostic purposes. A total of 305 cases of diagnosed gastric adenocarcinoma were enrolled, microRNAs (miRNAs) and their transcriptome sequencing data were obtained from the "The Cancer Genome Atlas." Blood samples were collected from GC patients before surgery and therapy. The miRNA levels and the expression of RNA were detected by real-time RT-PCR. Receiver operating characteristic analysis was used to evaluate the sensitivity and specificity of biomarkers. The combining predictors were established with the logistic regression analysis. Hundreds of miRNA were with higher area under curve (AUC) than 0.5; among them, nine miRNAs were with the highest AUC more than 0.90 and displayed strong diagnostic value. Moreover, the mir-17 level was correlated with tumor stage (p = 0.029), while mir-133b, mir-133a-2, and mir-1-2 levels were significantly correlated with race, tumor pathologic, and tumor stage (p < 0.05). The combination biomarker (mir-181a-1/KAT2B with a sensitivity of 95.83 % and specificity of 94.12 %) could be used as an independent diagnostic indicator for GC patients. For GC patients, mir-17, mir-133b, mir-133a-2, and mir-1-2 appear to be a potential novel predictor of tumor stage and preoperative and intraoperative diagnosis. The combination of miRNA and mRNA such as mir-181a-1/KAT2B (with a sensitivity of 95.83 % and specificity of 94.12 %) showed significant improvement in the diagnostic accuracy.

Endoscopic and Oncologic Outcomes of Endoscopic Resection for Superficial Esophageal Neoplasm

BACKGROUND/AIMS

Endoscopic resection (ER) of superficial esophageal neoplasm (SEN) is a technically difficult procedure. We investigated the clinical outcomes of ER for SEN to determine its feasibility and effectiveness.

METHODS

Subjects who underwent ER for SEN at Asan Medical Center between December 1996 and December 2010 were eligible. The clinical features of patients and tumors, histopathological characteristics, adverse events, ER results and survival were investigated.

RESULTS

A total of 129 patients underwent ER for 147 SENs. En bloc resection (EnR) was performed in 118 lesions (80.3%). Complete resection (CR) was accomplished in 128 lesions (86.5%), and curative resection (CuR) was performed in 118 lesions (79.7%). The EnR, CR, and CuR rates were significantly greater in the endoscopic submucosal dissection group when compared to those in the endoscopic resection group. Adverse events occurred in 22 patients (17.1%), including bleeding (n=2, 1.6%), perforation (n=12, 9.3%), and stricture (n=8, 6.2%). Local tumor recurrence occurred in 2.0% of patients during a median follow-up of 34.8 months. The 5-year overall and disease-specific survival rates were 94.0% and 97.5%, respectively.

CONCLUSIONS

ER is a feasible and effective method for the treatment of SEN as indicated by favorable clinical outcomes.