Features of early gastric cancer and gastric adenoma by enhanced-magnification endoscopy

Mucin phenotype and microvessels in early gastic cancer: Magnifying endoscopy with narrow band imaging

Backgrounds

In order to detect early gastric cancer (EGC), this research sought to assess the diagnostic utility of magnifying endoscopy (ME) as well as the significance of mucin phenotype and microvessel features.

Methods

402 individuals with an EGC diagnosis underwent endoscopic submucosal dissection (ESD) at the Department of ME between 2012 and 2020. After adjusting for image distortion, high-magnification endoscopic pictures were taken and examined to find microvessels in the area of interest. The microvessel density was measured as counts per square millimeter (counts/mm2) after segmentation, and the vascular bed's size was computed as a percentage of the area of interest. To identify certain properties of the microvessels, such as end-points, crossing points, branching sites, and connection points, further processing was done using skeletonized pixels.

Results

According to the research, undifferentiated tumors often lacked the MS pattern and showed an oval and tubular microsurface (MS) pattern, but differentiated EGC tumors usually lacked the MS pattern and presented a corkscrew MV pattern. Submucosal invasion was shown to be more strongly associated with the destructive MS pattern in differentiated tumors as opposed to undifferentiated tumors. While lesions with a corkscrew MV pattern and an antrum or body MS pattern revealed greater MUC5AC expression, lesions with a loop MV pattern indicated higher MUC2 expression. Furthermore, CD10 expression was higher in lesions with a papillary pattern and an antrum or body MS pattern.

Conclusion

These results imply that evaluating mucin phenotype and microvessel features in conjunction with magnifying endoscopy (ME) may be a useful diagnostic strategy for early gastric cancer (EGC) detection. Nevertheless, further investigation is required to confirm these findings and identify the best course of action for EGC diagnosis.

Endoscopic Resection of Early Gastric Cancer and Pre-Malignant Gastric Lesions

Early gastric cancer comprises gastric malignancies that are confined to the mucosa or submucosa, irrespective of lymph node metastasis. Endoscopic resection is currently pivotal for the management of such early lesions, and it is the recommended treatment for tumors presenting a very low risk of lymph node metastasis. In general, these lesions consist of two groups of differentiated mucosal adenocarcinomas: non-ulcerated lesions (regardless of their size) and small ulcerated lesions. Endoscopic submucosal dissection is the technique of choice in most cases. This procedure has high rates of complete histological resection while maintaining gastric anatomy and its functions, resulting in fewer adverse events than surgery and having a lesser impact on patient-reported quality of life. Nonetheless, approximately 20% of resected lesions do not fulfill curative criteria and demand further treatment, highlighting the importance of patient selection. Additionally, the preservation of the stomach results in a moderate risk of metachronous lesions, which underlines the need for surveillance. We review the current evidence regarding the endoscopic treatment of early gastric cancer, including the short-and long-term results and management after resection.

The usefulness of image-enhanced endoscopy to distinguish gastric carcinoma in tumors initially diagnosed as adenomas by endoscopic biopsy: A retrospective study

Superficial epithelial gastric neoplasms can be divided into adenomas and early carcinomas. Histological diagnosis by endoscopic forceps biopsy is crucial for the diagnosis and management of gastric neoplasms. It is difficult to distinguish features of gastric neoplasms in small biopsy specimens; hence, gastric carcinomas can be underdiagnosed as adenomas. Recent developments in image-enhanced endoscopy have improved the ability to differentiate between carcinomatous and non-carcinomatous lesions. To investigate the prevalence of gastric carcinoma in lesions initially diagnosed as adenomas by forceps biopsy and assess the usefulness of image-enhanced endoscopy in distinguishing carcinomas. A total of 142 lesions of gastric adenomas, diagnosed by biopsy and resected endoscopically between January 2010 and May 2020, were retrospectively evaluated. Images were captured by white-light endoscopy (WLE), magnifying endoscopy with narrow-band imaging (M-NBI), and magnifying endoscopy with acetic acid and narrow-band imaging (M-AANBI); they were analyzed and compared with histopathological results. The diagnostic performance of M-AANBI was compared with that of M-NBI. Of the 142 lesions, 58 (40.8%) were pathologically diagnosed as adenocarcinomas. On WLE images, a depressed macroscopic type and size ≥20 mm were significant predictors of carcinoma (P < .001); however, they displayed low sensitivities (32.8% and 41.4%, respectively). M-AANBI displayed significantly higher sensitivity, specificity, and accuracy for distinguishing carcinomas than M-NBI (94.8% vs 74.1%, 81.0% vs 72.6%, and 86.6% vs 73.2%, P < .05). In conclusion, carcinoma was prevalent in 40.8% of gastric lesions initially diagnosed as adenomas by forceps biopsy. M-AANBI may be more useful than M-NBI and WLE in distinguishing gastric carcinomas from adenomas.

Effect of adding acetic acid when performing magnifying endoscopy with narrow band imaging for diagnosis of Barrett's esophageal adenocarcinoma

Background and study aims  Magnifying endoscopy with narrow band imaging (M-NBI) was developed to diagnose Barrett's esophageal adenocarcinoma (BEA); however, this method remains challenging for inexperienced endoscopists. We aimed to evaluate a modified M-NBI technique that included spraying acetic acid (M-AANBI). Patients and methods  Eight endoscopists retrospectively examined 456 endoscopic images obtained from 28 patients with 29 endoscopically resected BEA lesions using three validation schemes: Validation 1 (260 images), wherein the diagnostic performances of M-NBI and M-AANBI were compared - the dataset included 65 images each of BEA and non-neoplastic Barrett's esophagus (NNBE) obtained using each modality; validation 2 (112 images), wherein 56 pairs of M-NBI and M-AANBI images were prepared from the same BEA and NNBE lesions, and diagnoses derived using M-NBI alone were compared to those obtained using both M-NBI and M-AANBI; and validation 3 (84 images), wherein the ease of identifying the BEA demarcation line (DL) was scored via a visual analog scale in 28 patients using magnifying endoscopy with white-light imaging (M-WLI), M-NBI, and M-AANBI. Results  For validation 1, M-AANBI was superior to M-NBI in terms of sensitivity (90.8 % vs. 64.6 %), specificity (98.5 % vs. 76.9 %), and accuracy (94.6 % vs. 70.4 %) (all P  < 0.05). For validation 2, the accuracy of M-NBI alone was significantly improved when combined with M-AANBI (from 70.5 % to 89.3 %; P  < 0.05). For validation 3, M-AANBI had the highest mean score for ease of DL recognition (8.75) compared to M-WLI (3.63) and M-NBI (6.25) (all P <  0.001). Conclusions  Using M-AANBI might improve the accuracy of BEA diagnosis.

Endoscopic Advances for Gastric Neoplasia Detection

This article explores advances in endoscopic neoplasia detection with supporting clinical evidence and future aims. The ability to detect early gastric neoplastic lesions amenable to curative endoscopic submucosal dissection provides the opportunity to decrease gastric cancer mortality rates. Newer imaging techniques offer enhanced views of mucosal and microvascular structures and show promise in differentiating benign from malignant lesions and improving targeted biopsies. Conventional chromoendoscopy is well studied and validated. Narrow band imaging demonstrates superiority over magnified white light. Autofluorescence imaging, i-scan, flexible spectral imaging color enhancement, and bright image enhanced endoscopy show promise but insufficient evidence to change current clinical practice.

Comparison of white-light endoscopy, optical-enhanced and acetic-acid magnifying endoscopy for detecting gastric intestinal metaplasia: A randomized trial

BACKGROUND

Gastric intestinal metaplasia (GIM) is a precancerous lesion of the stomach, which severely affects human life and health. Currently, a variety of endoscopic techniques are used to screen/evaluate GIM. Traditional white-light endoscopy (WLE) and acetic-acid chromoendoscopy combined with magnifying endoscopy (ME-AAC) are the interventions of choice due to their diagnostic efficacy for GIM. Optical-enhanced magnifying endoscopy (ME-OE) is a new virtual chromoendoscopy technique to identify GIM, which combines bandwidth-limited light and image enhancement processing technology to enhance the detection of mucosal and vascular details. We hypothesized that ME-OE is superior to WLE and ME-AAC in the evaluation of GIM.

AIM

To directly compare the diagnostic value of WLE, ME-AAC, and ME-OE for detection of GIM.

METHODS

A total of 156 patients were subjected to consecutive upper gastrointestinal endoscopy examinations using WLE, ME-AAC, and ME-OE. Histopathological findings were utilized as the reference standard. Accuracy, sensitivity, specificity, and positive and negative predictive values of the three endoscopy methods in the diagnosis of GIM were evaluated. Moreover, the time to diagnosis with ME-AAC and ME-OE was analyzed. Two experts and two non-experts evaluated the GIM images diagnosed using ME-OE, and diagnostic accuracy and intra- and inter-observer agreement were analyzed.

RESULTS

GIM was detected in 68 of 156 patients (43.6%). The accuracy of ME-OE was highest (91.7%), followed by ME-AAC (86.5%), while that of WLE (51.9%) was lowest. Per-site analysis showed that the overall diagnostic accuracy of ME-OE was higher than that of ME-AAC (P = 0.011) and WLE (P < 0.001). The average diagnosis time was lower in ME-OE than in ME-AAC (64 ± 7 s vs 151 ± 30 s, P < 0.001). Finally, the inter-observer agreement was strong for both experts (k = 0.862) and non-experts (k = 0.800). The internal consistency was strong for experts (k = 0.713, k = 0.724) and moderate for non-experts (k = 0.667, k = 0.598).

CONCLUSION

For endoscopists, especially experienced endoscopists, ME-OE is an efficient, convenient, and time-saving endoscopic technique that should be used for the diagnosis of GIM.

Endoscopic acanthosis nigricans appearance: A novel specific marker for diagnosis of low-grade intraepithelial neoplasia

BACKGROUND AND AIM

At present, there is no recognized diagnostic criteria for gastric low-grade intraepithelial neoplasia (LGIN). The purpose of this study was to determine whether an "endoscopic acanthosis nigricans appearance (EANA)" could be a useful endoscopic marker for distinguishing LGIN lesions from peripheral non-neoplastic tissues.

METHODS

A retrospective study was conducted on 638 cases of suspected superficial lesions with endoscopic images from white light endoscopy and magnifying endoscopy combined with narrow band imaging. According to the pathological results of accurate biopsies, those lesions were divided into three groups: a control group, an LGIN group, and an early gastric cancer (EGC) group.

RESULTS

According to the presence of EANAs, the sensitivity, specificity, positive predictive value, and negative predictive value for differentiating between the LGIN and control groups were 24.8%, 97.3%, 78.3%, and 76.6%, respectively. The sensitivity (84.1%) and negative predictive value (92.4%) were significantly improved by combining EANA with types IV-VI pit pattern. The intervening part and mean gray value of glands, representing microsurface features and microvascular variation, were significantly larger or higher in EANA lesions than in the surrounding non-neoplastic mucosa. LGIN with EANA was more likely to be present in lesions of type 0-IIa. In addition, the prevalence of EANAs in EGC was 16.7%.

CONCLUSION

An EANA could be used as an auxiliary indicator for a diagnosis of LGIN in suspected lesions. It could also play a potential assistive role in the diagnosis of EGC lesions.

Applications of acetic acid spray combined with narrow band imaging in diagnosis of early gastrointestinal cancers and precancerous lesions

Many new endoscopic techniques have been used for the diagnosis of early gastrointestinal cancers and precancerous lesions, such as magnifying endoscopy, narrow-band imaging (NBI), Fuji intelligent chromoendiscopy, i-scan imaging, confocal laser endomicroscopy, and chromoendoscopy (Lugol's iodine, indigo carmine, methylene blue, acetic acid, and crystal violet). Each technique has its own advantages and disadvantages (e.g., being expensive and prolonged examination duration). Spraying acetic acid onto the mucosal surface can enhance the recognition of mucosal surface architecture, and NBI has the advantage to display the microvascular morphology. Thus, acetic acid spray combined with NBI endoscopy can greatly improve the diagnosis of early gastrointestinal cancers and precancerous lesions. Since this combination has low cost and no adverse reactions, they can be used in primary hospitals without magnification endoscopy.

Magnifying Endoscopy with Blue Laser Imaging Improves the Microstructure Visualization in Early Gastric Cancer: Comparison of Magnifying Endoscopy with Narrow-Band Imaging

Backgrounds

Magnifying endoscopy with blue laser imaging (ME-BLI) for diagnosis of early gastric cancer (EGC) is as effective as magnifying endoscopy with narrow-band imaging (ME-NBI). However, there are different EGCs in microstructure visualization between ME-BLI and ME-NBI. This study aimed to clarify the pathological features of the EGCs, in which microstructure visualization was different between ME-NBI and ME-BLI.

Methods

EGCs were classified into groups A (irregular microsurface pattern (MSP) in ME-BLI and absent MSP in ME-NBI), B (irregular MSP in two modalities), or C (absent MSP in two modalities), according to the vessel plus surface classification. We compared the pathological features of EGCs between the three groups.

Results

17, four, and five lesions could be evaluated in detail in groups A, B and C, respectively. Well-differentiated adenocarcinomas with shallow crypts were more frequent in group A than in group B (58.8 and 0%, resp.). The mean crypt depth of group A was significantly shallower than that of group B (56 ± 20, 265 ± 64 μm, resp., P = 0.0002).

Conclusions

ME-BLI could better visualize the microstructures of the EGCs with shallow crypts compared with ME-NBI. Therefore, ME-BLI could enable a more accurate diagnosis of EGC with shallow crypts.

Acetic Acid Enhanced Narrow Band Imaging for the Diagnosis of Gastric Intestinal Metaplasia

Gastric intestinal metaplasia (GIM) is a precancerous lesion of the stomach. The detection of GIM using conventional white-light endoscopy (WLE) is difficult. In this study, we determined whether acetic acid-enhanced narrow band imaging (AA-NBI) improves the detection of GIM. A consecutive cohort of 132 individuals aged 40 years or older was subjected to upper gastrointestinal endoscopy using WLE, NBI and AA-NBI. The ability of the three methods to diagnose GIM in patients was compared. Histological assessment (per-patient and per-biopsy) was used for the accuracy assessment. Sixty-six (50.0%) out of the 132 individuals examined were found to have GIM, of which 44 (66.7%) were diagnosed correctly by NBI (sensitivity 66.7% and specificity 68.2%) and 58 (87.9%) were correctly identified by AA–NBI (sensitivity 87.9% and specificity 68.2%), as compared to only 22 (33.3%) by WLE (sensitivity 33.3% and specificity 28.8%). Therefore, the sensitivity of AA–NBI in the diagnosis of GIM was significantly higher than NBI (p<0.05) and WLE (p < 0.001). Our study indicates that AA-NBI can improve the accuracy of endoscopy-targeted biopsies for GIM.

Evidence based review of the impact of image enhanced endoscopy in the diagnosis of gastric disorders

Gastric cancer is the third most common cause of cancer-related death. Advanced stages of gastric cancers generally have grim prognosis. But, good prognosis can be achieved if such cancers are detected, diagnosed and resected at early stages. However, early gastric cancers and its precursors often produce only subtle mucosal changes and therefore quite commonly remain elusive at the conventional examination with white light endoscopy. Image-enhanced endoscopy makes mucosal lesions more conspicuous and can therefore potentially yield earlier and more accurate diagnoses. Recent years have seen growing work of research in support of various types of image enhanced endoscopy (IEE) techniques (e.g., dye-chromoendoscopy; magnification endoscopy; narrow-band imaging; flexible spectral imaging color enhancement; and I-SCAN) for a variety of gastric pathologies. In this review, we will examine the evidence for the utilization of various IEE techniques in the diagnosis of gastric disorders.

Role of endoscopy in early oesophageal cancer

Incidence of oesophageal adenocarcinoma has increased exponentially in the West over the past few decades. Following detection of advanced cancers, 5-year survival rates remain bleak, making identification of early neoplasia, which has a better outcome, important. Detection of subtle oesophageal lesions during endoscopy can be challenging, and advanced imaging techniques might improve their detection. High-definition endoscopy has become a standard in most endoscopy centres, and this technology probably provides better delineation of mucosal features than standard-definition endoscopy. Various image enhancement techniques are now available with the development of new electronics and software systems. Image enhancement with chromoendoscopy using dyes has been a cost-effective option for many years, yet these techniques have been replaced in some contexts by electronic chromoendoscopy, which can be used with the press of a button. However, Lugol's chromoendoscopy remains the gold standard to identify squamous dysplasia. Identification and characterization of subtle neoplastic lesions could help to target biopsies and perform endoscopic resection for better local staging and definitive therapy. In vivo histology with techniques such as confocal endomicroscopy could make endotherapy feasible within a shorter timescale than when relying on histology on tissue samples. Once early neoplasia is identified, treatments include endoscopic resection, endoscopic submucosal dissection or various ablative techniques. Endotherapy has the advantage of being a less invasive technique than oesophagectomy, and is associated with lower mortality and morbidity. Endoscopic ablation therapies have evolved over the past few years, with radiofrequency ablation showing the best results in terms of success rates and complications in Barrett dysplasia.

Useful condition of chromoendoscopy with indigo carmine and acetic acid for identifying a demarcation line prior to endoscopic submucosal dissection for early gastric cancer

Background

Identifying a precise demarcation line (DL) is indispensable for pathological complete en bloc endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). We evaluated the useful condition of chromoendoscopy with indigo carmine and acetic acid for marking dots around lesions before ESD for EGC.

Methods

We examined 98 consecutive patients with 109 intramucosal EGCs (mean diameter, 17.8 ± 12.4 mm; main histologic type, 96 intestinal and 13 diffuse) resected by en bloc ESD after chromoendoscopy with indigo carmine and acetic acid between December 2012 and February 2014. The DL was identified by this technique just before ESD (mean chromoendoscopy observation time, 71.6 s); subsequently, marking dots were placed around the EGC. EGCs were classified into two groups: useful for identifying the DL or useless. Clinicopathological characteristics and clinical outcomes were evaluated in each group.

Results

Forty-two of the 109 cases (38.5 %) were determined useful for chromoendoscopy with indigo carmine and acetic acid. Multivariate analysis with logistic regression showed that macroscopic type (protruded or flat elevated-type) and atrophic border (the oral side of tumor) were independently associated with the usefulness of chromoendoscopy using indigo carmine and acetic acid for identifying the DL of EGCs (P < 0.05). The histologically positive horizontal margin after ESD was 0 % (0/42) in useful cases, and 7.5 % (5/67) in useless cases.

Conclusions

Before ESD, chromoendoscopy with indigo carmine and acetic acid can be used for creating precise markings in protruded or flat elevated-type EGC or at the atrophic border on the oral side of EGCs.

Magnifying endoscopy simple diagnostic algorithm for early gastric cancer (MESDA-G)

Gastric cancer is the third leading cause of cancer death worldwide. Early detection and accurate diagnosis of mucosal cancer is desirable in order to achieve decreased mortality; cause-specific survival of patients with early gastric cancer is reported to exceed 95%. Endoscopy is the functional modality to detect early cancer; however, the procedure is not definitive when using conventional white-light imaging. In contrast, magnifying narrow-band imaging (M-NBI), a novel endoscopic technology, is a powerful tool for characterizing gastric mucosal lesions because it can visualize the microvascular architecture and microsurface structure. To date, many reports on the diagnosis of early gastric cancer by M-NBI, including multicenter prospective randomized studies conducted in Japan, have been published in peer-reviewed international journals. Based on these published data, we devised a proposal for a diagnostic strategy for gastric mucosal cancer using M-NBI to simplify the process of diagnosis and improve accuracy. Herein, we recommend a diagnostic algorithm for early gastric cancer using magnifying endoscopy.

Endoscopic prediction of tumor margin and invasive depth in early gastric cancer

Gastric cancer (GC) is the fifth most common cancer and the third leading cause of cancer-related deaths in the world. The prognosis of GC is clearly associated with the tumor stage, with a 5-year overall survival rate for early gastric cancer (EGC) exceeding 90%, which is significantly higher than that of advanced gastric cancer. Endoscopic resection, including endoscopic mucosal resection and endoscopic submucosal dissection, has been adopted in recent decades as the first treatment option of EGC in many countries for its minimal invasion and high curative rate. However, the horizontal and vertical margins are related to the curative resection of EGC and the prognosis of patients. Thus the accurate prediction of the tumor boundary and its invasive depth before treatment counts for much in planning the most appropriate treatment strategy and promising curative resection. To date, various endoscopic techniques have been identified to play a role in pretreatment evaluation, such as white light endoscopy, chromoendoscopy, narrow band imaging and endoscopic ultrasonography. This article aimed to summarize the diagnostic methods, applications and limitations of these different endoscopic techniques for identifying tumor horizontal and vertical margins in EGC, helping to increase preoperative evaluation of capabilities and to improve the curative resection rate of EGC.

The accuracy of confocal laser endomicroscopy, narrow band imaging, and chromoendoscopy for the detection of atrophic gastritis

OBJECTIVE

The aim of this study was to compare chromoendoscopy (CE), narrow band imaging (NBI), and confocal laser endomicroscopy (CLE) in diagnosing atrophic gastritis.

BACKGROUNDS

Atrophic gastritis, especially metaplastic atrophy, has been shown to be a risk factor for gastric cancer. Some advanced endoscopic techniques have been used to diagnose atrophic gastritis. However, it is still difficult to diagnose atrophy with a high degree of accuracy.

STUDY

In total, 253 gastric sites from 87 consecutive patients were examined by NBI, CE, and CLE, and in turn endoscopic diagnoses were made. Histologic diagnoses of biopsies taken from the observed sites served as gold standards. Comparisons were made of the sensitivity, specificity, and accuracy between each endoscopic technique for obtaining a diagnosis atrophic gastritis.

RESULTS

NBI was found to be equivalent to CE in classifying gastric pits (κ=0.904). The CLE had a higher sensitivity (P=0.035), specificity (P=0.049), and accuracy (P=0.002) than CE for diagnosing atrophic gastritis. The sensitivity and specificity of CLE for diagnosing nonmetaplastic atrophy were 86.76% and 91.89%, respectively, and for metaplastic atrophy were 91.94% and 96.86%, respectively. Interobserver and intraobserver agreements of CLE for predicting histopathologic gastritis were both high (0.938 and 0.895, respectively).

CONCLUSIONS

CLE is reliable for real-time assessment of atrophic gastritis and is also able to differentiate metaplastic from nonmetaplastic atrophy.

Magnification endoscopy with acetic acid enhancement and a narrow-band imaging system for pit pattern diagnosis of colorectal neoplasms

BACKGROUND AND GOALS

Pit pattern (PP) analysis of colorectal neoplasms using magnification chromoendoscopy with crystal violet (CV-MCE) is useful for predicting histologic features, but it is time consuming. Capillary pattern analysis by magnification endoscopy with narrow-band imaging (NBIME) is a useful and simpler procedure, but its diagnostic accuracy may be inferior to CV-MCE. NBIME with acetic acid enhancement (A-NBIME) is effective for rapid visualization of gastric mucosal microstructures. We performed a prospective study to compare the diagnostic reliability and feasibility of A-NBIME and CV-MCE in PP diagnosis of colorectal neoplasms.

STUDY

The present study consisted of 3 protocols: Study-1 assessed 56 colorectal lesions photographed with A-NBIME and CV-MCE, and the endoscopic images were reviewed by 3 experts to compare the diagnostic concordance; study-2 assessed 202 colorectal lesions photographed with A-NBIME in 116 consecutive patients and the correlation between PP and histologic findings; study-3 randomly allocated 100 patients with colorectal lesions equally to A-NBIME and CV-MCE, and compared the procedure time and visible ratio of PP.

RESULTS

The κ value for interobserver agreement for A-NBIME and CV-MCE was 0.71 (0.66 to 0.75) and 0.80 (0.75 to 0.85), respectively. Intraobserver agreement between modalities for each reviewer was 0.79 (0.70 to 0.88), 0.80 (0.71 to 0.90), and 0.74 (0.67 to 0.82). Non-neoplastic polyps and massively invasive submucosal adenocarcinomas were statistically related to type II and type VI-H/VN. The procedure time was statistically shorter with A-NBIME than with CV-MCE (31 vs. 81 s), and the visible ratio of PP was equivalent (98.9% vs. 98.3%).

CONCLUSIONS

A-NBIME is comparable with CV-MCE in PP diagnosis of colorectal neoplasms and is a simpler technique.

Diagnosis of early gastric cancer using narrow band imaging and acetic acid

AIM: To determine whether the endoscopic findings of depressed-type early gastric cancers (EGCs) could precisely predict the histological type.

METHODS: Ninety depressed-type EGCs in 72 patients were macroscopically and histologically identified. We evaluated the microvascular (MV) and mucosal surface (MS) patterns of depressed-type EGCs using magnifying endoscopy (ME) with narrow-band imaging (NBI) (NBI-ME) and ME enhanced by 1.5% acetic acid, respectively. First, depressed-type EGCs were classified according to MV pattern by NBI-ME. Subsequently, EGCs unclassified by MV pattern were classified according to MS pattern by enhanced ME (EME) images obtained from the same angle.

RESULTS: We classified the depressed-type EGCs into the following 2 MV patterns using NBI-ME: a fine-network pattern that indicated differentiated adenocarcinoma (25/25, 100%) and a corkscrew pattern that likely indicated undifferentiated adenocarcinoma (18/23, 78.3%). However, 42 of the 90 (46.7%) lesions could not be classified into MV patterns by NBI-ME. These unclassified lesions were then evaluated for MS patterns using EME, which classified 33 (81.0%) lesions as MS patterns, diagnosed as differentiated adenocarcinoma. As a result, 76 of the 90 (84.4%) lesions were matched with histological diagnoses using a combination of NBI-ME and EME.

CONCLUSION: A combination of NBI-ME and EME was useful in predicting the histological type of depressed-type EGC.

Chromoendoscopy of gastric adenoma using an acetic acid indigocarmine mixture

AIM: To investigate the usefulness of chromoendoscopy, using an acetic acid indigocarmine mixture (AIM), for gastric adenoma diagnosed by forceps biopsy.

METHODS: A total of 54 lesions in 45 patients diagnosed as gastric adenoma by forceps biopsy were prospectively enrolled in this study and treated by endoscopic submucosal dissection (ESD) between January 2011 and January 2012. AIM-chromoendoscopy (AIM-CE) was performed followed by ESD. AIM solution was sprinkled and images were recorded every 30 s for 3 min. Clinical characteristics such as tumor size (< 2 cm, ≥ 2 cm), surface color in white light endoscopy (WLE) (whitish, normochromic or reddish), macroscopic appearance (flat or elevated, depressed), and reddish change in AIM-CE were selected as valuables.

RESULTS: En bloc resection was achieved in all 54 cases, with curative resection of fifty two lesions (96.3%). Twenty three lesions (42.6%) were diagnosed as well-differentiated adenocarcinoma and the remaining 31 lesions (57.4%) were gastric adenoma. All adenocarcinoma lesions were well-differentiated tubular adenocarcinomas and were restricted within the mucosal layer. The sensitivity of reddish color change in AIM-CE is significantly higher than that in WLE (vs tumor size ≥ 2 cm, P = 0.016, vs normochromic or reddish surface color, P = 0.046, vs depressed macroscopic type, P = 0.0030). On the other hand, no significant differences were found in the specificity and accuracy. In univariate analysis, normochromic or reddish surface color in WLE (OR = 3.7, 95%CI: 1.2-12, P = 0.022) and reddish change in AIM-CE (OR = 14, 95%CI: 3.8-70, P < 0.001) were significantly related to diagnosis of early gastric cancer (EGC). In multivariate analysis, only reddish change in AIM-CE (OR = 11, 95%CI: 2.3-66, P = 0.0022) was a significant factor associated with diagnosis of EGC.

CONCLUSION: AIM-CE may have potential for screening EGC in patients initially diagnosed as gastric adenoma by forceps biopsy.

Enhanced magnifying endoscopy for differential diagnosis of superficial gastric lesions identified with white-light endoscopy

BACKGROUND

Various techniques using magnifying endoscopy (ME) and chromoendoscopy are being developed to enhance images of gastrointestinal tumor. The aim of this study was to evaluate the diagnostic performance of ME enhanced by acetic acid-indigo carmine mixture (ME-AIM) and ME enhanced with narrow-band imaging (ME-NBI) for differential diagnosis of superficial gastric lesions identified with conventional white-light endoscopy (WLE).

METHODS

Patients with superficial gastric lesions picked up with WLE were enrolled in the study. ME-NBI and ME-AIM were used to further characterize the lesions. All images of the lesions were evaluated by four skilled endoscopists blinded to the clinical data. The microarchitectural patterns in the lesions were analyzed with reference to the "VS classification" system.

RESULTS

A total of 643 lesions (mean diameter, 7 mm) from 508 patients (316 men, 192 women; mean age, 63 years) were evaluated. Pathologically, 24 of the 643 lesions were diagnosed as gastric cancer; the others were noncancerous lesions. For diagnosis of gastric cancer, the negative predictive value of each of the three magnified findings (irregular microvascular pattern, irregular microsurface pattern, and demarcation line) was high (nearly 100 %). According to the "VS classification" system, either ME-NBI or ME-AIM had a higher specificity (99.5 % or 99.4 % vs. 89.5 %, P < 0.001) and accuracy (99.2 % or 98.9 % vs. 89.0 %, P < 0.001) than WLE, and ME-AIM was not superior to ME-NBI for identifying carcinoma.

CONCLUSIONS

Enhanced ME is useful for correctly diagnosing early gastric cancer, and in contrast with ME-AIM, ME-NBI is a more feasible and efficient method for clinical practice.

Endoscopic acetic acid-Lugol's iodine double staining for diagnosis of early esophageal cancer

AIM: To evaluate the value of endoscopic acetic acid-Lugol's iodine double staining in the diagnosis of early esophagus cancer.

METHODS: Patients with suspicious lesions first underwent Lugol's iodine staining, and the patients who showed no staining or poor staining were randomly divided into two groups: an acetic acid-Lugol's iodine double staining group (n = 30) and a Lugol's iodine staining group (n = 30). The double staining group underwent spraying with acetic acid first and then with Lugol's iodine solution. The mucosa was considered abnormal when mucosal discoloration or poor coloration developed after double staining, and biopsy of abnormal mucosa for histopathological examination was performed.

RESULTS: Eight (26.67%) patients of the double staining group were diagnosed with esophageal cancer by biopsy histopathological examination, containing 6 cases of esophageal squamous cell carcinoma and 2 cases of adenocarcinoma. Postoperative pathological diagnosis confirmed that all the 8 cases were early esophageal cancer. In the control group, 2 (6.67%) cases were found with esophageal squamous cell carcinoma by biopsy histopathological examination, and postoperative pathological diagnosis confirmed that both were early esophageal cancer. The detection rate of esophageal cancer in the double staining group was significantly higher than that in the Lugol's iodine staining group (P < 0.05). The detection rate of esophageal squamous cell carcinoma showed no significant difference between the two groups (20.00% vs 6.67%, P > 0.05).

CONCLUSION: Endoscopic acetic acid-Lugol's iodine double staining can improve the detection rate of early esophageal cancer, especially adenocarcinoma.

Magnified and enhanced computed virtual chromoendoscopy in gastric neoplasia: A feasibility study

AIM: To evaluate the feasibility of a new computed virtual chromoendoscopy (CVC) device (M i-scan) in the diagnosis of gastric neoplasia.

METHODS: Patients with superficial lesions no larger than 1.0 cm found during high definition endoscopy were included. Those with advanced or obviously protruded or depressed lesions, lesions larger than 1.0 cm and/or lesions which were not amenable to observation by zoom function were excluded. The endoscopist was required to give the real-time descriptions of surface pit patterns of the lesions, based on surface pattern classification of enhanced magnification endoscopy. According to previous reports, types I-III represent non-neoplastic lesions, and types IV-V represent neoplastic lesions. Diagnosis with M i-scan and biopsy was performed before histopathological diagnosis. Magnified images of gastric lesions with and without enhancement were collected for further analysis. The diagnostic yield of real-time M i-scan and effects on magnification image quality by tone enhancement (TE), surface enhancement (SE) and color enhancement (CE) were calculated. The selected images were sent to another endoscopist. The endoscopist rated the image quality of each lesion at 3 levels. Ratings of image quality were based on visualization of pit pattern, vessel and demarcation line.

RESULTS: One hundred and eighty-three patients were recruited. Five patients were excluded for advanced gastric lesions, 1 patient was excluded for poor preparation and 2 patients were excluded for superficial lesions larger than 1.0 cm; 132 patients were excluded for no lesions found by high definition endoscopy. In the end, 43 patients with 43 lesions were included. Histopathology revealed 10 inflammation, 14 atrophy, 10 metaplasia, 1 low grade dysplasia (LGD), 5 high grade dysplasia (HGD) and 3 cancers. For 7 lesions classified into type I, histopathology revealed 6 atrophy and 1 metaplasia; for 10 lesions classified into type II, histopathology revealed 2 inflammation, 7 atrophy and 1 metaplasia; for 10 lesions classified into type III, histopathology revealed 1 inflammation, 8 metaplasia and 1 LGD; for 9 lesions classified into type IV, histopathology revealed 4 inflammation, 1 atrophy and 4 HGD; for 7 lesions classified into type V, histopathology revealed 3 inflammation, 1 HGD and 3 cancers. A total of 172 still images, including 43 images by white light (MWL) and 129 images by M i-scan (43 with TE, 43 with SE and 43 with CE), were selected and sent to the endoscopist who did the analysis. General image quality of M i-scan with TE and SE was significantly better than that of MWL (TE, 4.55 ± 1.07; SE, 4.30 ± 1.02; MWL, 3.25 ± 0.99; P < 0.001). Visualization of pit pattern was significantly improved by M i-scan with SE (1.93 ± 0.25 vs 1.50 ± 0.50, P < 0.001). Microvessel visualization was significantly improved by M i-scan with TE (1.23 ± 0.78 vs 0.76 ± 0.73, P < 0.001). Demarcation line visualization was improved by M i-scan with both TE and SE (TE, 1.75 ± 0.52; SE, 1.56 ± 0.59; MWL, 0.98 ± 0.44; P < 0.001). M i-scan with CE did not show any significant improvements of image quality in general or in the 3 key parameters. Although M i-scan with TE and SE slightly increased the diagnostic yield of MWL, there was no significant difference (P > 0.1).

CONCLUSION: Although digital enhancement improves the image quality of magnification endoscopy, its value in improving the diagnostic yield seems to be limited.

Screening for precancerous lesions of upper gastrointestinal tract: from the endoscopists' viewpoint

Upper gastrointestinal tract cancers are one of the most important leading causes of cancer death worldwide. Diagnosis at late stages always brings about poor outcome of these malignancies. The early detection of precancerous or early cancerous lesions of gastrointestinal tract is therefore of utmost importance to improve the overall outcome and maintain a good quality of life of patients. The desire of endoscopists to visualize the invisibles under conventional white-light endoscopy has accelerated the advancements in endoscopy technologies. Nowadays, image-enhanced endoscopy which utilizes optical- or dye-based contrasting techniques has been widely applied in endoscopic screening program of gastrointestinal tract malignancies. These contrasting endoscopic technologies not only improve the visualization of early foci missed by conventional endoscopy, but also gain the insight of histopathology and tumor invasiveness, that is so-called optical biopsy. Here, we will review the application of advanced endoscopy technique in screening program of upper gastrointestinal tract cancers.

Utility of peppermint oil for endoscopic diagnosis of gastric tumors

We investigated whether peppermint oil (PO) is useful for endoscopic diagnosis of gastric tumors without magnifying endoscopy. Twenty-six patients diagnosed with gastric tumors were examined. Endoscopic images were recorded by white light (WL) and narrow band imaging (NBI) without magnifying endoscopy. After PO administration, images were recorded again by WL and NBI (PO+WL and PO+NBI). The clarity of tumor margins and the effect of PO on the clarity of tumor margins were scored. The mean scores for clarity of tumor margins were 3.6 points in WL, 4 in NBI, 4.3 in PO+WL, and 4.3 in PO+NBI. The scores of WL and NBI showed a tendency to rise by PO. The mean scores for the effect of PO on the clarity of tumor margins were 2.7 in WL and 2.5 in NBI. Therefore, we conclude that PO is useful for endoscopic diagnosis of the margin of gastric tumors.

Application of magnifying narrow-band imaging endoscopy for diagnosis of early gastric cancer and precancerous lesion

Background

Gastric carcinoma is the second commonest cause of cancer deaths worldwide. Early detection and diagnosis of gastric cancer in the stomach is important for improving the prognosis of gastric cancer. This retrospective study was designed to investigate the value of magnifying narrow-band imaging (NBI) in the diagnosis of precancerous lesions and early gastric cancer.

Methods

This study included 122 patients who were diagnosed with early gastric cancer or precancerous gastric lesions by endoscopy. The patients underwent an examination with conventional endoscopy, magnifying NBI, and magnifying chromoendoscopy. Images resolution was evaluated, and the morphology, pit patterns and blood capillary forms of lesions were analyzed. The presence of gastric carcinoma and high grade intraepithelial neoplasia in the biopsy samples was considered as a positive pathological result, which is used to assess accuracy of endoscopic diagnosis.

Results

For image resolution, magnifying NBI and magnifying chromoendoscopy were significantly superior to magnifying conventional endoscopy in morphology, pit pattern and blood capillary form (P < 0.01), and magnifying NBI was significantly superior to magnifying chromoendoscopy in blood capillary form (P < 0.01). IV, V₁, and VI type of gastric pit pattern were detected in 14 cases, 43 cases, and 17 cases in patients with high grade intraepithelial neoplasia, respectively. V₁ and VI type of gastric pit pattern were detected in 9 cases and 39 cases in patients with early gastric cancer, respectively. The presence of irregular minute vessels and variation in the caliber of vessels was found in 109 cases. The accuracy, sensitivity, specificity, false positive rate and false negative rate for diagnosis of early gastric cancer and precancerous gastric lesions were 68.9%, 95.1%, 63.1%, 24.5%, and 32.4% for conventional endoscopy, 93.6%, 92.7%, 94.5%, 5.7%, and 6.9% for magnifying NBI, and 91.3%, 88.6%, 93.2%, 13.2%, and 21.48% for magnifying chromoendoscopy, respectively.

Conclusions

This study demonstrates that magnifying NBI is superior to conventional endoscopy in the diagnosis of early gastric cancer and precancerous gastric lesions, and can be used for screening early malignancies of the stomach.

Application of endoscopy in the diagnosis of gastric cancer

Gastric cancer is the most common cancer of the gastrointestinal tract, whose incidence and mortality are always high. Endoscopy and pathological examination are the most basic ways to diagnose this malignancy, but the rate of its early diagnosis was very low. In recent years, the emergence of chromoendoscopy, magnification endoscopy, endoscopic ultrasonography, narrow band imaging endoscopy, autofluorescence imaging endoscopy and confocal laser endomicroscopy has significantly improved the detection of gastric cancer, and these new techniques play an important role in the diagnosis of this disease. Here we summarize the application of endoscopy in the diagnosis of gastric cancer.

Magnifying chromoendoscopic findings of early gastric cancer and gastric adenoma

PURPOSE

In the field of colorectal cancer and adenoma, Kudo's classification of pit pattern with magnifying chromocolonoscopy using crystal violet (CV) staining is now accepted. Magnifying endoscopy using narrow band imaging has been used for the diagnosis of gastric carcinoma; the characteristic findings of microvascular patterns have been demonstrated. However, there was limited information on magnified endoscopic findings with CV staining for gastric neoplasms in terms of their pit patterns.

METHODS

Magnifying chromoendoscopy with CV was performed in 175 patients with early gastric cancer and 18 with gastric adenoma, prior to treatment. Surface patterns of gastric tumors were classified into five types: (1) long tubular pit pattern, (2) irregular size pit pattern, (3) small round pit pattern, (4) destroyed pit pattern, and (5) non-structural pattern.

RESULTS

Long tubular pit pattern was most common in gastric adenoma. Well differentiated adenocarcinoma and papillary adenocarcinoma tended to show different size of pit pattern or destroyed pit pattern. Small round pit pattern was most commonly seen in moderately differentiated adenocarcinoma. Non-structural pattern was most frequently observed in poorly differentiated adenocarcinoma and signet ring cell carcinoma (P < 0.0001).

CONCLUSION

For gastric neoplasms, magnifying endoscopy may help predict histopathological type.

Endomicroscopy of intestinal metaplasia and gastric cancer

In vivo histologic diagnosis of gastric intestinal metaplasia (GIM) and gastric cancer (GC) can be achieved by confocal laser endomicroscopy (CLE). This review describes the endomicroscopic features of GIM and GC and reviews their clinical applications. Differentiation of phenotypes of GIM and GC by using CLE is also discussed.

Narrow band imaging for the detection of gastric intestinal metaplasia and dysplasia during surveillance endoscopy

Background Surveillance of premalignant gastric lesions relies mainly on random biopsy sampling. Narrow band imaging (NBI) may enhance the accuracy of endoscopic surveillance of intestinal metaplasia (IM) and dysplasia.We aimed to compare the yield of NBI to white light endoscopy (WLE) in the surveillance of patients with (IMa)and dysplasia.Methods Patients with previously identified gastric IM or dysplasia underwent a surveillance endoscopy. Both WLE and NBI were performed in all patients during a single procedure. The sensitivity of WLE and NBI for the detection of premalignant lesions was calculated by correlating endoscopic findings to histological diagnosis.Results Forty-three patients (28 males and 15 females,mean age 59 years) were included. IM was diagnosed in 27 patients; 20 were detected by NBI and WLE, four solely by NBI and three by random biopsies only. Dysplasia was detected in seven patients by WLE and NBI and in two patients by random biopsies only. Sixty-eight endoscopically detected lesions contained IM: 47 were detected by WLE and NBI, 21 by NBI only. Nine endoscopically detected lesions demonstrated dysplasia: eight were detected by WLE and NBI, one was detected by NBI only.The sensitivity, specificity, positive and negative predictive values for detection of premalignant lesions were 71, 58,65 and 65% for NBI and 51, 67, 62 and 55% for WLE,respectively.Conclusions NBI increases the diagnostic yield for detection of advanced premalignant gastric lesions compared to routine WLE.

Acetic acid-indigo carmine chromoendoscopy for delineating early gastric cancers: its usefulness according to histological type

Background

Endoscopic treatments, such as endoscopic submucosal dissection (ESD) and laparoscopic gastrectomy, are increasingly used to treat a subset of patients with early gastric cancer (EGC). To achieve successful outcomes, it is very important to accurately determine the lateral extent of the tumor. Therefore, we investigated the diagnostic performance of chromoendoscopy using indigo carmine dye added to acetic acid (AI chromoendoscopy) in delineating differentiated or undifferentiated adenocarcinomas in patients with EGC.

Methods

We prospectively included 151 lesions of 141 patients that had an endoscopic diagnosis of EGC. All the lesions were examined by conventional endoscopy and AI chromoendoscopy before ESD or laparoscopic gastrectomy. The border clarification between the lesion and the normal mucosa was classified as distinct or indistinct before and after AI chromoendoscopy.

Results

The borders of the lesions were distinct in 66.9% (101/151) with conventional endoscopy and in 84.1% (127/151) with AI chromoendoscopy (P < 0.001). Compared with conventional endoscopy, AI chromoendoscopy clarified the border in a significantly higher percentage of differentiated adenocarcinomas (74/108 [68.5%] vs 97/108 [89.8%], respectively, P < 0.001). However, the border clarification rate for undifferentiated adenocarcinomas did not differ between conventional endoscopy and AI chromoendoscopy (27/43 [62.8%] vs 30/43 [70.0%], respectively, P = 0.494).

Conclusions

AI chromoendoscopy is useful in determining the lateral extent of EGCs. However, its usefulness is reduced in undifferentiated adenocarcinomas.

Ease of early gastric cancer demarcation recognition: a comparison of four magnifying endoscopy methods

BACKGROUND AND AIM

Various techniques using magnifying endoscopy (ME) have been developed to enhance images of early gastric cancer (EGC) demarcations, which are often obscure. We investigated four ME methods to determine which is most effective in enhancing the recognition of EGC demarcations: conventional ME (CME), ME with narrow band imaging (NBI-ME), enhanced-magnification endoscopy with acetic acid (EME), and ME with NBI and acetic acid (NBI-EME).

METHODS

Thirty-seven successive patients having a total of 40 EGCs participated in the investigation. The endoscope was fixed and magnification images of EGC demarcations in each patient were recorded using four different ME methods (CME, NBI-ME, EME and NBI-EME). Eight experts and eight non-experts scored each of the four images of each lesion for ease of recognition of demarcation (1 to 4, with 4 being easiest).

RESULTS

The mean scores of expert and non-expert judges, respectively, for images acquired using each technique were: CME 1.23, 1.24; NBI-ME 2.61, 2.95; EME 2.62, 2.32 and NBI-EME 3.54, 3.50. There were significant differences between the mean scores for the four techniques (P < 0.0001) using one-way repeated-measures anova. In a Bonferroni's multiple comparison, the average scores (expert and non-expert) of images acquired using NBI-EME were significantly higher than those acquired using other methods; images acquired by NBI-ME or EME also scored significantly higher than those by CME. Non-experts also scored NBI-ME images significantly higher than CME and EME images.

CONCLUSIONS

Early gastric cancer demarcations were recognized most easily using NBI-EME, and more easily using EME or NBI-ME than CME.

Chromoendoscopy

Chromoendoscopy involves the use of stains or dyes during endoscopy to improve the visualization and characterization of the gastrointestinal mucosa. Its main clinical application is the detection of dysplasia or early cancer of the gastrointestinal tract in individuals with pre-malignant conditions or hereditary and environmental factors that predispose them to cancer. The utility of chromoendoscopy has been mostly studied in squamous cell carcinoma of the esophagus, Barrett's esophagus, gastric cancer, colorectal polyps, and chronic ulcerative colitis. Although chromoendoscopy has been shown to be feasible and safe, several limitations have prevented its widespread use in endoscopy. Despite this, chromoendoscopy remains a useful adjunct to standard white light endoscopy in the visualization of mucosal lesions, which may potentially improve tissue diagnosis and impact patient care.

Novel chromoendoscopic method using an acetic acid-indigocarmine mixture for diagnostic accuracy in delineating the margin of early gastric cancers

BACKGROUND AND AIM

Recent endoscopic imaging techniques for recognition of unclear lesions in the stomach (e.g. narrow band imaging, magnifying endoscopy) require special equipment and therefore are not commonly used. The aim of the present study was to estimate the accuracy of a new chromoendoscopic method using an acetic acid-indigo carmine mixture (AIM) in diagnosing early gastric cancers (EGC).

METHODS

Studied were 108 EGC lesions in 104 patients. EGC were initially observed by white light (WL) after which indigo carmine (IC) solution was sprinkled onto the gastric mucosa. Images by WL and IC observation were recorded by a digital filing system. After washing away IC solution with water, AIM solution was sprinkled onto the gastric mucosa and images were recorded. Margin lines of EGC determined by each observation were drawn on recorded images by graphic software for comparison with resected specimens. After lines were similarly drawn on images of resected specimens, the extent of the lesions was compared with that determined by endoscopic images.

RESULTS

Diagnostic accuracy of WL, IC, and AIM observations were 50.0%, 75.9% and 90.7%, respectively. No adverse events occurred with the AIM method.

CONCLUSIONS

This chromoendoscopic method can be used to delineate the margin of EGC accurately, easily, safely and inexpensively.

Usefulness of autofluorescence imaging for estimating the extent of gastric neoplastic lesions: a prospective multicenter study

BACKGROUND/AIMS

The aim of this study was to determine whether the margin of early to be detected gastric cancer (EGC) and gastric adenoma is easier to be detected with autofluorescence imaging (AFI) than with white-light endoscopy (WLE).

METHODS

A total of 102 lesions (48 EGCs and 54 gastric adenomas) found in 98 patients were removed endoscopically or surgically. The measured length of each pathology specimen was compared with the lengths estimated using WLE, AFI, and chromoendoscopy.

RESULTS

The lesions could be discriminated from surrounding mucosa by AFI in 86 cases (84.3%). The detection rates were similar for elevated lesions (85.1%) and flat/depressed lesions (82.9%, p=0.770). In terms of histology, the detection rate was slightly higher for adenomas (90.7%) than for cancer (77.1%, p=0.058). The estimated length was shorter than the pathologic length in 31.4% of cases when using WLE and 22.1% of cases when using AFI (p=0.168). The resection range was larger for EMR than for AFI in 24 of 80 cases (30.0%).

CONCLUSIONS

WLE tends to underestimate the size of EGCs, whereas AFI tends to overestimate their size.

Chromoendoscopy with indigo carmine dye added to acetic acid in the diagnosis of gastric neoplasia: a prospective comparative study

BACKGROUND

Conventional endoscopy and chromoendoscopy with indigo carmine dye are usually performed for recognizing adequate tumor-negative lateral margins for successful endoscopic resection of gastric neoplasia. However, chromoendoscopy with indigo carmine dye added to acetic acid has not been used for this purpose.

OBJECTIVE

Our purpose was to compare the diagnostic performance of chromoendoscopy with indigo carmine dye added to acetic acid with that of conventional endoscopy and chromoendoscopy with indigo carmine dye or acetic acid alone.

DESIGN

Prospective study.

SETTING

Social Insurance Funabashi Central Hospital.

PATIENTS

Forty-seven consecutive patients (53 lesions) with early gastric cancer and gastric adenomas who underwent endoscopic submucosal dissection (ESD) from April 2006 to July 2007 were studied.

INTERVENTIONS

All the lesions were examined by the endoscopic modalities before ESD, and the resected specimens were analyzed histopathologically.

MAIN OUTCOME MEASUREMENTS

Two endoscopists independently evaluated the diagnostic performance of each image in terms of recognition of tumor borders with reference to macroscopic and histopathologic findings of resected specimens. We also conducted a substudy to assess interobserver variability.

RESULTS

There was good interobserver agreement between the 2 endoscopists in this study (kappa index = 0.764). The diagnostic performance of chromoendoscopy with indigo carmine dye added to acetic acid was significantly greater than that of any of the other modalities (vs each: P < .005).

CONCLUSIONS

The diagnostic performance of chromoendoscopy with indigo carmine dye added to acetic acid was better compared with conventional endoscopy and chromoendoscopy by using only indigo carmine dye or acetic acid. The applicability of this method for gastric neoplasia merits further investigation.

The acetic acid + indigocarmine method in the delineation of gastric cancer

BACKGROUND AND AIM

For the purpose of precise preoperative diagnosis that ensures complete endoscopic resection, it is important to accurately determine the lateral spread of gastric cancer lesions. The acetic acid + indigocarmine (AI) method used by us has been found to meet this need. This paper reports its usefulness in the determination of lateral spread of gastric cancer before endoscopic submucosal dissection (ESD).

METHODS

The present study was conducted in 114 patients who were operated on for an early-stage gastric cancer, after determining the lateral spread of cancerous lesions by the AI method, between September 2005 and December 2006. The negative lateral stump reaction rate obtained in ESD was conducted in areas delineated by the AI method. The borderline clarification rate obtained by the AI method and the indigocarmine (I) method were compared between the lesions with and without clear borders under observation with the naked eye.

RESULTS

The lateral stump after ESD conducted using the AI method was histologically negative in 111 of the 114 patients (97%). The lesion spread was clarified by the AI method in 103 patients (90%): 55 (95%) and 48 (86%) patients with and without clear macroscopic lesion borders, respectively. Compared to the I method, the AI method clarified the lesion spread in a significantly higher percentage of patients with macroscopically unclear lesion borders (P = 0.015).

CONCLUSION

The present study stresses that the AI method should be used to conduct ESD more safely and accurately in patients with well or moderately differentiated adenocarcinoma.

Classification of gastric pit patterns by confocal endomicroscopy

BACKGROUND

Confocal endomicroscopy is a newly developed endoscopic imaging technology that produces 1000-fold magnification cross-sectional images of the GI surface and subsurface tissue during routine endoscopy. The gastric pit patterns identified by confocal endomicroscopy and correlation with histopathologic examination have not yet been established.

OBJECTIVE

Our purpose was to explore the appearance of various kinds of gastric pits and clarify the relationship between gastric pit patterns and the histopathologic findings.

DESIGN

Descriptive study.

SETTING

Qilu Hospital, Shandong University, Jinan, China.

PATIENTS

A total of 132 consecutive patients underwent confocal endomicroscopy after 7 healthy volunteers had been examined in vivo and 10 samples resected from 10 patients with gastric cancer had been examined ex vivo by use of confocal endomicroscopy. The confocal images obtained from the 132 patients were compared with the histopathologic findings of the biopsy specimens from the corresponding confocal imaging sites in a prospective and blinded fashion.

MAIN OUTCOME MEASUREMENTS

The relationship between the pit patterns and the histopathologic findings.

RESULTS

Gastric pit patterns were classified into 7 types. Normal mucosa with fundic glands mainly showed type A (round pits), and corporal mucosa with histologic gastritis showed type B (noncontinuous short rod-like); normal mucosa with pyloric glands mainly showed type C (continuous short rod-like), and antral mucosa with histologic gastritis showed type D (elongated and tortuous branch-like). Goblet cells were easily distinguished by confocal endomicroscopy in intestinal metaplasia mucosa, which showed type F. The sensitivity and specificity of the type E pattern for predicting gastric atrophy were 83.6% and 99.6%, respectively. Corresponding values of the type G pattern for predicting gastric cancer were 90.0% and 99.4%.

LIMITATIONS

No data on interobserver and intraobserver variability.

CONCLUSIONS

The patterns of gastric pits identified by confocal endomicroscopy correlate well with the histopathologic findings. Confocal endomicroscopy may prove useful in predicting histopathologic diagnoses during routine endoscopic procedures.

Surface pattern classification by enhanced-magnification endoscopy for identifying early gastric cancers

BACKGROUND

The correlation between fine surface patterns of gastric mucosal lesions and early gastric cancer is not sufficiently clear.

OBJECTIVE

To evaluate the efficacy of surface pattern classification by enhanced-magnification endoscopy (EME) for identifying early gastric cancers.

DESIGN

Observational study.

SETTING

All procedures were performed at Mie University Hospital.

PATIENTS

A total of 380 consecutive patients who underwent EGD by using magnification endoscopy. Among these subjects were found 250 newly detected lesions suspected of being gastric cancer.

METHODS

Conventional magnification endoscopy (CME), magnification chromoendoscopy (MCE), and EME were performed, and surface patterns of lesions were classified into 5 types: type I, small round pits of uniform size and shape; type II, slit-like pits; type III, gyrus and villous patterns; type IV, irregular arrangement and size; and type V, destructive pattern. Biopsy specimens were obtained from all lesions.

MAIN OUTCOME MEASUREMENTS

Correlation between surface pattern classification by EME and histopathologic findings of early gastric cancer.

RESULTS

Surface patterns were evident by CME/MCE in only 66.4% (166/250) of lesions but in 100% (250/250) of lesions by EME. Classification by EME was as follows: type I, 52 lesions; type II, 12; type III, 146; type IV, 32; and type V, 8. By histopathologic examination, 16 early gastric cancers were detected between type IV or V lesions. Thus, classification of types IV-V strongly correlated with the presence of gastric cancer (sensitivity 100%, specificity 89.7%).

LIMITATIONS

Single-center study.

CONCLUSIONS

Surface pattern classification by EME may be useful for identifying early gastric cancers.

Papillary adenocarcinoma occurring in a gastric hyperplastic polyp observed by magnifying endoscopy and treated with endoscopic mucosal resection

The patient was a 75-year-old man. He had been diagnosed with gastric hyperplastic polyp 4 years previously. The color of the apex of this polyp was whitish. Magnifying endoscopy findings revealed disappearance of the mucosal microstructure with irregular branched capillaries at the top of the polyp. Endoscopic mucosal resection (EMR) was performed. Histological examination revealed that a part of the polyp surface was replaced with papillary adenocarcinoma. Diagnosis of papillary adenocarcinoma in a hyperplastic polyp with mucosal invasion was made. Magnifying endoscopy was useful for the detection of gastric cancer occurring in the hyperplastic polyp in the present case.