Clinical and endoscopic characterization of depressed gastric adenoma

Intestinal-type gastric dysplasia in Helicobacter pylori-naïve patients

Gastric dysplasia and gastric cancer in Helicobacter pylori (Hp)-naïve patients usually exhibit a gastric phenotype, reflecting gastric mucosa without intestinal metaplasia (IM). We showed that intestinal-type gastric dysplasia (IGD) rarely occurs in the Hp-naïve stomach. In the last 10 years, we treated 1760 gastric dysplasia and gastric cancer patients, with 3.6% (63/1760) being Hp-naïve. Among these, ten were diagnosed with 14 IGDs and enrolled in this retrospective analysis. All lesions were observed by white-light endoscopy (WLE) and narrow-band imaging with magnification endoscopy (NBIME). We analyzed their endoscopic and microscopic features and patient demographics. Five men and five women aged 64 ± 21 years were included. WLE showed the depressed lesions mimicking a benign raised erosion in the prepyloric compartment. Multiple growths were confirmed in 30% (3/10) of patients. NBIME showed a near-regular microstructure and capillaries in 50% (7/14) of lesions with a gastritis-like appearance. Histologically, background mucosa was non-atrophic pyloric gland tissue, but 40.0% of samples (4/10) contained sporadic IM. Most of the lesions (8/14) were low-grade dysplasia, and others had a high-grade component, with one progressing to intramucosal carcinoma. The neoplastic surface was widely covered with foveolar epithelium in 57.1% (8/14). Immunohistochemically, neoplastic cells expressed CDX2 in all patients (14/14), MUC2 and CD10 in 92.9% (13/14), MUC5AC in 14% (2/14), and no expression of MUC6, showing an intestinal phenotype. Ki-67 was overexpressed with a mean labeling index of 58.3 ± 38.5%, and p-53 was overexpressed in 92.9% (13/14), regardless of the dysplastic grade. The IGD rarely occurs in Hp-naïve patients with distinctive clinicopathologic characteristics.

Endoscopic Management of Early Gastric Adenocarcinoma and Preinvasive Gastric Lesions

Early gastric cancer (ECG) can be difficult to diagnose endoscopically. Endoscopists should be familiar with subtle changes and endoscopic features of EGC. Chromoendoscopy and image-enhanced endoscopy improve diagnostic accuracy and facilitate endoscopic resection. Endoscopic submucosal dissection is a preferred endoscopic technique for resection of EGC and offers a comparable overall survival to surgical resection. Endoscopic management of benign gastric epithelial polyps (fundic gland polyps, hyperplastic polyps, and gastric adenoma) depends on patient symptomatology, patient's comorbidities (eg, familial syndromes), lesions' characteristics, and risk of malignant transformation. This article provides an overview of endoscopic management of EGC and common premalignant gastric lesions.

Can magnifying endoscopy with narrow-band imaging discriminate between carcinomas and low grade adenomas in gastric superficial elevated lesions?

Background and study aims: The aim of this study was to investigate the capability of magnifying endoscopy with narrow-band imaging (ME-NBI) to discriminate between early carcinomas (EC) and low grade adenomas (LGA) in gastric superficial elevated epithelial neoplasias. Patients and methods: We investigated 100 consecutive cases of gastric superficial elevated epithelial neoplasias that were removed using endoscopic submucosal dissection. The pathological diagnostic criteria were based on the revised Vienna classification; category 4 (mucosal high grade neoplasia) and category 5 (submucosal invasion by carcinoma) lesions were diagnosed as EC, whereas category 3 (mucosal low grade neoplasia) lesions were diagnosed as LGA. The associations between the postoperative pathological diagnoses and the ME-NBI findings were analyzed, and included the shape, specification, and area of irregularity in the microvascular architecture (MV) and the microsurface structure (MS). Results: Seventy-nine EC and 21 LGA cases diagnosed postoperatively were evaluated retrospectively. The lesion size (median; range (mm)) was significantly larger in the EC group (14; 2 - 95) compared to the LGA group (5; 2 - 16) (P < 0.001). Wavy forms in the MV shapes (P = 0.031), extension in the MV specifications (P = 0.035), and area with MV irregularity (P = 0.001) were found to be statistically significant predictive findings for EC. Villous forms in the MS shapes (P = 0.026), enlargement in the MS specifications (P = 0.044), and area with MS irregularity (P = 0.021) were also found to be statistically significant predictive findings for EC. The rates of preoperative sensitivity, specificity, and diagnostic accuracy of ME-NBI for discriminating EC were 86.1 %, 38.9 %, and 75 %, respectively. Conclusions: The present study suggests that ME-NBI is useful for the differential diagnosis of EC and LGA in gastric superficial elevated epithelial neoplasias.

STUDY REGISTRATION

UMIN000012925.

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.

Morphologic and Histologic Changes in Gastric Adenomas After Helicobacter pylori Eradication: A Long-Term Prospective Analysis

BACKGROUND

Helicobacter pylori infection causes gastric neoplasia via development of chronic atrophic gastritis and intestinal metaplasia. The effect of H. pylori eradication on pre-existing gastric neoplasias is still controversial. The aim of this study was to use long-term observation to clarify morphologic and histologic changes in gastric adenomas following H. pylori eradication.

MATERIALS AND METHODS

Twenty-seven patients with gastric adenomas (revised Vienna classification category 3 or 4.1) who underwent successful H. pylori eradication between April 1996 and December 1997 were followed up at regular intervals with endoscopic and histologic examination. The association between macroscopic and histologic regressions of the lesions and the following patient and lesion characteristics was assessed with univariate analysis: follow-up period, age, sex, serum pepsinogen level, lesion size, lesion location, and histologic gastritis.

RESULTS

The mean follow-up period was 91.9 months (range 44-181 months). Twelve lesions (44.4%) showed macroscopic regression, of which 7 (25.9% of the total) also showed histologic regression, with the mean duration from H. pylori eradication to complete macroscopic and histologic regression being 19.9 months. The other 15 lesions (55.6%) remained stable macroscopically and histologically, of which 6 (22.2% of the total) progressed to malignancy during the follow-up period. Univariate analysis revealed that female sex (p = .005), smaller lesion size (p = .025), higher baseline serum pepsinogen II level (p = .041), and absence of intestinal metaplasia in the greater curvature of the corpus (p = .026) were significantly associated with complete regression.

CONCLUSIONS

Helicobacter pylori eradication may induce regression in some gastric adenomas.

Trimodal imaging endoscopy reduces the risk of synchronous gastric neoplasia

BACKGROUND AND AIM

The accurate detection of synchronous neoplasia is important to reduce the risk of recurrence after endoscopic resection. Trimodal imaging endoscopy (TMIE) was developed for this purpose. Our aim was to compare the effects of TMIE and white-light imaging endoscopy (WLIE) in gastric neoplasia detection.

PATIENTS AND METHODS

Six hundred and seventy-eight patients with gastric dysplasia or cancer initially treated by endoscopic resection and who underwent follow-up endoscopy were analyzed retrospectively. Gastric neoplasia detected within 1 year of endoscopic resection was defined as synchronous disease. WLIE or TMIE was used to detect another gastric neoplasia before endoscopic resection.

RESULTS

Synchronous gastric neoplasia was observed in 41 patients (6%), and occurred more frequently after the resection of carcinoma than dysplasia (8.5 vs. 4.6%, P=0.04). TMIE significantly reduced the frequency of synchronous gastric lesions than WLIE (2.3 vs. 9.3%, P<0.01). TMIE was more effective than WLIE in reducing the risk of missing a synchronous gastric lesion after adjusting for lesion multiplicity, experience, and resected lesion pathology (hazard ratio, 0.32; 95% confidence interval, 0.108-0.762).

CONCLUSION

The risk of missing synchronous gastric neoplasia is higher after endoscopic resection for gastric cancer than dysplasia, but is reduced by TMIE. TMIE before endoscopic treatment can be useful in decreasing the risk of synchronous gastric neoplasia.

Gastric cancer: prevention, screening and early diagnosis

Gastric cancer continues to be an important healthcare problem from a global perspective. Most of the cases in the Western world are diagnosed at late stages when the treatment is largely ineffective. Helicobacter pylori (H. pylori) infection is a well-established carcinogen for gastric cancer. While lifestyle factors are important, the efficacy of interventions in their modification, as in the use of antioxidant supplements, is unconvincing. No organized screening programs can be found outside Asia (Japan and South Korea). Although several screening approaches have been proposed, including indirect atrophy detection by measuring pepsinogen in the circulation, none of them have so far been implemented, and more study data is required to justify any implementation. Mass eradication of H. pylori in high-risk areas tends to be cost-effective, but its adverse effects and resistance remain a concern. Searches for new screening biomarkers, including microRNA and cancer-autoantibody panels, as well as detection of volatile organic compounds in the breath, are in progress. Endoscopy with a proper biopsy follow-up remains the standard for early detection of cancer and related premalignant lesions. At the same time, new advanced high-resolution endoscopic technologies are showing promising results with respect to diagnosing mucosal lesions visually and targeting each biopsy. New histological risk stratifications (classifications), including OLGA and OLGIM, have recently been developed. This review addresses the current means for gastric cancer primary and secondary prevention, the available and emerging methods for screening, and new developments in endoscopic detection of early lesions of the stomach.

Systematic review of the diagnosis of gastric premalignant conditions and neoplasia with high-resolution endoscopic technologies

AIM. The aim of the article is to systematically review the current evidence on the diagnostic use of narrow band imaging (NBI), flexible spectral imaging color enhancement (FICE) and endoscopic image enhancement technology i-scan endoscopies for gastric precancerous and cancerous lesions. MATERIALS AND METHODS. Original manuscripts were searched in PubMed until October 2012. Pertinent data were collected and pooled diagnostic accuracy measures were estimated when possible. RESULTs. In total, 38 studies were evaluated. Thirty-one studies were included for NBI and 7 studies for FICE assessment in this systematic review. No article was found meeting inclusion criteria for i-scan endoscopy. The most defined and evaluated outcomes were cancer-related (n = 26). Quality Assessment of Diagnostic Accuracy Studies score varied from 9 to 12 (out of 14). Only few studies assessed the interobserver reliability. On a patient level analysis, NBI's pooled sensitivity, specificity and diagnostic odds ratio were 0.67 (95% CI: 0.61-0.73), 0.81 (95% CI: 0.76-0.85) and 22.71 (95% CI: 12.53-41.1), respectively for diagnosing normal mucosa; 0.86 (95% CI: 0.82-0.90), 0.77 (95% CI: 0.73-0.80) and 17.01 (95% CI: 1.4-207.2) for intestinal metaplasia and 0.90 (95% CI: 0.84-0.94), 0.83 (95% CI: 0.80-0.86) and 47.61 (95% CI: 4.61-491.34) for dysplasia. Owing to the insufficient data and different definitions, we could not aggregate the results for FICE. CONCLUSION. Gastric pattern descriptions have been proposed for NBI and FICE studies by gathering all descriptions in one single description. The classification systems varied between studies, a single description of gastric mucosal features with HR--scopes or at least per technology--will have to be agreed on.

Narrow band imaging versus white light gastroscopy in detecting potentially premalignant gastric lesions: a randomized prospective crossover study

BACKGROUND AND AIMS

Narrow band imaging (NBI) detects mucosal surface details (pit pattern) as well as the microvasculature pattern of mucosa. In premalignant conditions the pattern and regularity of pits and microvasculature are altered. We aimed to assess whether NBI is superior to conventional white light gastroscopy (WLG) in detecting potentially premalignant gastric lesions.

PATIENTS AND METHODS

We conducted a randomized prospective crossover study from January 2009 to July 2009. Patients above 45 years of age with dyspepsia in absence of alarm symptoms underwent gastric mucosal examination using WLG and NBI in the same session by different endoscopists who were blinded to each other's endoscopy findings. Biopsy was taken if required at the end of the second gastroscopy after a third observer reviewed reports of both scopists. The yield of gastric potentially premalignant lesions (atrophic gastritis, intestinal metaplasia, dysplasia, adenomatous polyp) was compared for both procedures.

RESULTS

Two hundred [mean age 52.3 (6.4) years, males-66 %] patients participated in the study. Thirty-two patients were diagnosed to have potentially premalignant lesions using both modalities. No patient had early gastric cancer. WLG detected lesions in 17 patients (atrophic gastritis in 12, atrophic gastritis with intestinal metaplasia in 5) and NBI in 31 patients (atrophic gastritis in 22, atrophic gastritis with intestinal metaplasia in 9). The sensitivity of lesion detection by NBI was significantly higher than WLG (p = 0.001).

CONCLUSIONS

NBI was superior to WLG for detection of atrophic gastritis and intestinal metaplasia.

Magnifying endoscopy with narrow-band imaging helps determine the management of gastric adenomas

BACKGROUND

There are no clear clinical criteria for the management of gastric lesions diagnosed as adenomas (Vienna classification category 3) by pre-treatment biopsy. In the present study, we examined the feasibility of magnifying endoscopy with narrow-band imaging (ME-NBI) in discriminating early gastric cancers (Vienna classification category 4 or 5) from adenomas in lesions diagnosed as adenomas by pre-treatment biopsy.

METHODS

This was a single-center cross-sectional retrospective study at a tertiary referral center. One hundred thirty-seven consecutive cases of gastric lesions diagnosed as adenomas in pre-treatment forceps biopsy were examined with conventional non-magnifying endoscopy under white light, non-magnifying chromoendoscopy, and ME-NBI. We investigated the association between the final pathological diagnoses (carcinoma or adenoma) and the following factors: lesion size (mm), color (red or white), macroscopic type (depressed or others), presence of ulceration, and positive ME-NBI finding. The presence of an irregular microvascular pattern or an irregular microsurface pattern with a demarcation line between the lesion and the surrounding area was regarded as a positive ME-NBI finding.

RESULTS

Lesion size was significantly larger in carcinomas than adenomas (P = 0.005). Depressed lesion (P = 0.011), red color (P < 0.001), and positive ME-NBI finding (P < 0.001) were significant predictive factors for carcinoma. Multivariate logistic regression confirmed that red color (odds ratio [OR] 3.04, 95% confidence interval [CI] 1.26-7.34, P = 0.14) and a positive ME-NBI finding (OR 13.68, 95% CI 5.69-32.88, P < 0.001) were independent predictive factors for carcinomas. A positive ME-NBI finding was the strongest predictive factor.

CONCLUSIONS

ME-NBI is useful in planning the management of lesions diagnosed as adenomas by pre-treatment forceps biopsy.

Current clinical applications of magnifying endoscopy with narrow band imaging in the stomach

Narrow band imaging (NBI), in conjunction with magnifying endoscopy (ME), has arisen more and more attention in the area of advanced endoscopy. By enhancing the mucosal microvascular architecture and surface pattern, it is feasible to use ME-NBI to identify subtle changes associated with gastric inflammation, atrophy, intestinal metaplasia, and early gastric cancer. The new technique thus plays a valuable role in therapeutic decision-making, endoscopic treatment process, postoperative evaluation, and follow-up examination. To date, many criteria or evaluation method of ME-NBI has been proposed. This paper aims to summarize the various diagnosing classifications and the current clinical applications of ME-NBI in the stomach.

Clinical characterization of gastric lesions initially diagnosed as low-grade adenomas on forceps biopsy

AIM

The aim of this study was to elucidate characteristics of gastric lesions that are initially diagnosed as low-grade adenomas and to establish appropriate treatment.

METHODS

We retrospectively reviewed 231 lesions initially diagnosed as gastric adenomas. All forceps biopsy samples were histologically diagnosed as category 3 low-grade adenomas according to the revised Vienna Classification. All patients underwent endoscopic resection with endoscopic findings and post-resection diagnoses evaluated subsequently.

RESULTS

Sixty-three lesions were initially diagnosed as depressed adenomas, and 168 lesions were diagnosed as protruding adenomas. The depressed lesions were significantly smaller (11.6 ± 5.0 mm) than the protruding lesions (17.0 ± 10.8 mm) (P < 0.001). Diagnoses reclassified to category 4 mucosal high-grade neoplasia (i.e. high-grade adenoma, adenocarcinoma in adenoma and adenocarcinoma) were more frequent among depressed lesions (52.4%) than among protruding lesions (31.0%) (P = 0.004). Multivariate analysis of all 231 lesions showed that lesion size larger than 20 mm (P < 0.001) and depressed appearance (including central depression) (P < 0.001) were significant independent factors suggesting cancer. For the 168 protruding lesions, lesion size larger than 20 mm (P < 0.001) and central depression (P < 0.001) were significant independent factors suggesting cancer. For the 63 depressed lesions, lesion size larger than 15 mm (P = 0.016) and a moth-eaten appearance (P = 0.017) were significant independent factors in the pre-treatment diagnosis of cancer.

CONCLUSIONS

Adenocarcinoma lesions were often found in depressed lesions and protruding lesions with central depression. Endoscopic resection for total biopsy is recommended, even if forceps biopsy indicates low-grade adenoma, as pre-treatment biopsy may be inadequate for an accurate histological diagnosis.

Can magnifying endoscopy with narrow band imaging be useful for low grade adenomas in preoperative biopsy specimens?

BACKGROUND

In biopsy specimens with low grade adenomas, it is often difficult to identify the presence of high grade adenomas or early carcinomas and low grade adenomas preoperatively, and clear guidelines have not yet been defined for the applicability of endoscopic treatment to low grade adenomas identified in biopsy specimens.

METHODS

We aimed to clarify the usefulness of magnifying endoscopy with narrow band imaging (NBI) compared to conventional white light endoscopy for diagnosing actual high grade adenomas or early carcinomas with low grade adenomas, using the VS (microvascular pattern [V] and microsurface pattern [S]) classification for low grade adenomas in biopsy specimens. The study cohort consisted of 135 patients who were diagnosed with low grade adenomas in preoperative biopsy specimens and received endoscopic submucosal dissection.

RESULTS

In the elevated type of lesion, magnifying endoscopy with NBI diagnosed high grade adenomas or early carcinomas at a higher sensitivity and specificity than conventional white light endoscopy (82.4 vs. 70.6%, P = 0.391, 97.3 vs. 54.7%, P < 0.0001). In the depressed macroscopic type of lesion, magnifying endoscopy with NBI also diagnosed high grade adenomas or early carcinomas at a higher sensitivity (95.5 vs. 68.2%, P = 0.0459) than conventional white light endoscopy. Although the specificity was high, at 100%, the difference when compared to conventional white light endoscopy was not significant (100 vs. 100%, P > 0.99).

CONCLUSIONS

For low grade adenomas in biopsy specimens, it is vital to take sufficient consideration of endoscopic findings and not take action based only on the biopsy results. If a decision is made using the VS classification with magnifying endoscopy with NBI, actual high grade adenomas or early carcinomas can be differentiated from low grade adenomas so that endoscopic treatment can be performed more strictly.

Magnifying narrowband imaging is more accurate than conventional white-light imaging in diagnosis of gastric mucosal cancer

BACKGROUND & AIMS

It is difficult to accurately diagnose patients with depressed gastric mucosal cancer based on conventional white-light imaging (C-WLI) endoscopy. We compared the real-time diagnostic yield of C-WLI for small, depressed gastric mucosal cancers with that of magnifying narrow-band imaging (M-NBI).

METHODS

We performed a multicenter, prospective, randomized, controlled trial of patients with undiagnosed depressed lesions ≤10 mm in diameter identified by esophagogastroduodenoscopy. Patients were randomly assigned to groups that were analyzed by C-WLI (n = 176) or M-NBI (n = 177) immediately after detection; the C-WLI group received M-NBI after C-WLI. We compared the diagnostic accuracy, sensitivity, and specificity between C-WLI and M-NBI and assessed the diagnostic yield of M-NBI conducted in conjunction with C-WLI.

RESULTS

Overall, 40 gastric cancers (20 in each group) were identified. The median diagnostic values for M-NBI and C-WLI were as follows: accuracy, 90.4% and 64.8%; sensitivity, 60.0% and 40.0%; and specificity, 94.3% and 67.9%, respectively. The accuracy and specificity of M-NBI were greater than those of C-WLI (P < .001); the difference in sensitivity was not significant (P = .34). The combination of M-NBI with C-WLI significantly enhanced performance compared with C-WLI alone; accuracy increased from (median) 64.8% to 96.6% (P < .001), sensitivity increased from 40.0% to 95.0% (P < .001), and specificity increased from 67.9% to 96.8% (P < .001).

CONCLUSIONS

M-NBI, in conjunction with C-WLI, identifies small, depressed gastric mucosal cancers with 96.6% accuracy, 95.0% sensitivity, and 96.8% specificity. These values are better than for C-WLI or M-NBI alone.

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.

Frozen Section Biopsy to Evaluation of Obscure Lateral Resection Margins during Gastric Endoscopic Submucosal Dissection for Early Gastric Cancer

Purpose

To determine the diagnostic utility of a frozen section biopsy in patients undergoing endoscopic submucosal dissection (ESD) for early gastric neoplasms with obscure margins even with chromoendoscopy using acetic acid and indigo carmine (AI chromoendoscopy).

Materials and Methods

The lateral spread of early gastric neoplasms was unclear even following AI chromoendoscopy in 38 patients who underwent ESD between June 2007 and May 2011. Frozen section biopsies were obtained by agreement of the degree of lateral spread between two endoscopists. Thus, frozen section biopsies were obtained from 23 patients (FBx group) and not in the other 15 patients (AI group).

Results

No significant differences were observed for size, histology, invasive depth, and location of lesions between the AI and FBx groups. No false positive or false negative results were observed in the frozen section diagnoses. Adenocarcinoma was revealed in three patients and tubular adenoma in one, thereby changing the delineation of lesion extent and achieving free lateral margins. The rates of free lateral resection margins and curative resection were significantly higher in the FBx group than those in the AI group.

Conclusions

Frozen section biopsy can help endoscopists perform more safe and accurate ESD in patients with early gastric neoplasm.

Prospective study of the evaluation of the usefulness of tumor typing by narrow band imaging for the differential diagnosis of gastric adenoma and well-differentiated adenocarcinoma

BACKGROUND AND AIM

Presently, the differential diagnosis of gastric adenoma and well-differentiated adenocarcinoma by endoscopy is very difficult. We carried out magnifying endoscopy with narrow band imaging (NBI) in lesions that required discrimination between gastric adenoma and well-differentiated adenocarcinoma, and prospectively evaluated whether the tumor typing that we propose is useful for their differential diagnosis.

METHODS

The materials were 93 lesions that required differential diagnosis between gastric adenoma and well-differentiated adenocarcinoma among the gastric epithelial tumors for which endoscopic treatment was planned at three facilities during the 14 months between November 2008 and December 2009. According to the typing method proposed by our facility based on images of the mucosal ultrastructure and microvessels obtained by magnified endoscopy combined with NBI, type I-II and type III-V lesions were diagnosed as gastric adenoma and well-differentiated adenocarcinoma, respectively, before endoscopic treatment, and the accuracy of the diagnoses were prospectively examined by comparing them with the postoperative pathological findings.

RESULTS

Of the 93 lesions, 87 could be typed into the five types of our typing method, but six lesions could not be classified. The 87 lesions consisted of 16 type I, 12 type II, 29 type III, 27 type IV, and three type V lesions. The percentages of accurate preoperative diagnoses of types I-II as adenoma and types III-V as well-differentiated adenocarcinoma were 79% and 93%, respectively.

CONCLUSIONS

The tumor typing based on NBI was useful for the endoscopic differentiation of gastric adenoma and well-differentiated adenocarcinoma.

The usefulness of magnifying endoscopy with narrow-band imaging to distinguish carcinoma in flat elevated lesions in the stomach diagnosed as adenoma by using biopsy samples

BACKGROUND

Therapeutic strategies for flat elevated (0-IIa) lesions in the stomach diagnosed as adenoma by biopsy are currently not established, because some difficulties have previously been reported in the evaluation of vascular patterns alone for the differential diagnosis between adenoma and carcinoma.

OBJECTIVE

We attempted to evaluate the 0-IIa lesions diagnosed as adenoma by using magnifying endoscopy with narrow-band imaging (MENBI) to distinguish them as either adenoma or carcinoma.

SETTING

Department of Gastroenterology, Fujita Health University.

PATIENTS

Fourteen adenomatous lesions (6 adenomas and 8 carcinomas confirmed postoperatively) diagnosed with preoperative biopsies from patients who had undergone endoscopic submucosal dissection were evaluated.

INTERVENTIONS

We selected 5 sites per lesion for MENBI. Selected sites were divided into superficial structures (SSs) and irregular microvascular patterns (IMVPs).

MAIN OUTCOME MEASUREMENTS

The rate of SSs and IMVPs in adenoma and carcinoma.

RESULTS

Significant SSs were tubular in the adenoma and unclear in the carcinoma. Regarding IMVP subcategories, (1) slight intrastructual irregular microvascular patterns (ISIMVPs) accounted for 97%, (2) severe ISIMVPs accounted for 0%, (3) fine networks accounted for 3%, and (4) corkscrews accounted for 0% of cases in the adenomas. The corresponding proportions in the carcinomas were (1) 40%, (2) 15%, (3) 45%, and (4) 0%. Severe ISIMVPs and fine networks were significant findings for carcinomas.

LIMITATIONS

The number of cases was limited.

CONCLUSIONS

Our combined evaluation method using MENBI offers the ability to establish proper therapeutic strategies for lesions that are difficult to identify as adenoma or carcinoma.

Magnifying narrow-band imaging versus magnifying white-light imaging for the differential diagnosis of gastric small depressive lesions: a prospective study

BACKGROUND

The accurate diagnosis of gastric small depressive lesions (SDLs), including gastritis and cancerous lesions, is difficult with conventional endoscopy when using white-light imaging (WLI). Narrow-band imaging (NBI) is expected to make a more accurate diagnosis of gastric SDLs than WLI because it provides better visualization of the mucosal surface and microvascular architecture when combined with magnifying endoscopy.

OBJECTIVE

To compare the real-time diagnostic accuracy of magnifying WLI and magnifying NBI for gastric SDLs.

DESIGN

Prospective study.

SETTING

National Cancer Center Hospital East, Kashiwa, Japan.

PATIENTS

Fifty-seven lesions in 53 consecutive patients were analyzed: 30 cancers and 27 benign lesions.

INTERVENTIONS

If previously undiagnosed gastric SDLs smaller than 10 mm were identified during an endoscopic examination, magnifying observation with both WLI and NBI was performed for each SDL. Endoscopic diagnosis of SDLs was made by each method on site.

MAIN OUTCOME MEASUREMENTS

The diagnostic accuracy and the time required for diagnosis.

RESULTS

The diagnostic accuracy was significantly higher for NBI than for WLI (79% vs 44%; P = .0001), as was its sensitivity (70% vs 33%; P = .0005). The diagnostic specificity of NBI (89%) was higher than that of WLI (67%), but the difference was not statistically significant. The time required for the diagnosis was equivalent with both methods.

LIMITATIONS

Single-center study, small sample size.

CONCLUSIONS

Adding NBI to the WLI examination is essential for making an accurate diagnosis of gastric SDLs compared with magnifying WLI alone. (UMIN Clinical Trials Registry identification number C000000421).

Improving visualization techniques by narrow band imaging and magnification endoscopy

Endoscopy plays an important role in the early detection of gastrointestinal tract neoplasms. Using conventional white light or dye-based image enhanced endoscopy, it has been difficult to assess pre-malignant and early neoplastic lesions precisely. However, narrow band imaging (NBI) dramatically improves the detection of these lesions, particularly in combination with magnifying endoscopy. This allows the endoscopist to accomplish accurate diagnosis. Such enhanced detection of pre-malignant and early neoplastic lesions in the gastrointestinal tract should allow better targeting of biopsy, improved and more appropriate treatment, and thereby contribute to optimal quality of life and patient survival.

Usefulness of magnifying endoscopy in post-endoscopic resection scar for early gastric neoplasm: A prospective short-term follow-up endoscopy study

AIM: To investigate the relationship between post-endoscopic resection (ER) scars on magnifying endoscopy (ME) and the pathological diagnosis in order to validate the clinical significance of ME.

METHODS: From January, 2007 to June, 2008, 124 patients with 129 post-ER scar lesions were enrolled. Mucosal pit patterns on ME were compared with conventional endoscopy (CE) findings and histological results obtained from targeted biopsies.

RESULTS: CE findings showed nodular scars (53/129), erythematous scars (85/129), and ulcerative scars (4/129). The post-ER scars were classified into four pit patterns of sulci and ridges on ME: (I) 47 round; (II) 54 short rod or tubular; (III) 19 branched or gyrus-like; and (IV) 9 destroyed pits. Sensitivity and specificity were 88.9% and 62.5%, respectively, by the presence of nodularity on CE. Erythematous lesions were high sensitivity (100%), but specificity was as low as 36.7%. The range of the positive predictive value (PPV) on CE was as low as 10.6%-25%. Nine type IV pit patterns were diagnosed as tumor lesions, and 120 cases of type I-III pit patterns revealed non-neoplastic lesions. Thus, the sensitivity, specificity, and the PPV of ME were 100%.

CONCLUSION: ME findings can detect the presence of tumor in post-ER scar lesions, and make evident the biopsy target site in short-term follow-up. Further large-scale and long-term studies are needed to determine whether ME can replace endoscopic biopsy.

Meta-analysis: narrow band imaging for lesion characterization in the colon, oesophagus, duodenal ampulla and lung

BACKGROUND

Narrow band imaging is a new endoscopic technology that highlights mucosal surface structures and microcapillaries, which may be indicative of neoplastic change.

AIM

To assess the diagnostic precision of narrow band imaging for the diagnosis of epithelial neoplasia compared to conventional histology both overall and in specific organs.

METHODS

We performed a meta-analysis of studies which compared narow band imaging-based diagnosis of neoplasia with histopathology as the gold standard. Search terms: 'endoscopy' and 'narrow band imaging'.

RESULTS

Five hundred and eighty-two patients and 1108 lesions in 11 studies were included. Overall, sensitivity was 0.94 (95% confidence interval 0.92-0.95), specificity 0.83 (0.80-0.86); weighted area under the curve was 0.96 (standard error 0.02), diagnostic odds ratio (DOR) 72.74 (34.11-155.15). DORs were 66.65 (25.84-171.90), 61.19 (7.09-527.97), 69.74 (8.04-605.24) for colon, oesophagus and lung respectively. Studies with more than 50 patients had higher diagnostic precision, relative DOR 4.96 (1.28-19.27), P = 0.022. There was no difference in accuracy between microvessel and mucosal (pit) pattern based measures, relative DOR 1.29 (0.05-35.16), P = 0.87. There was significant heterogeneity overall between studies, Q = 31.2, P = 0.003.

CONCLUSION

Narrow band imaging is accurate with high diagnostic precision for in vivo diagnosis of neoplasia across a range of organs, using simple microvessel-based measures.

Perspective on the practical indications of endoscopic submucosal dissection of gastrointestinal neoplasms

Endoscopic submucosal dissection (ESD) is a new endoluminal therapeutic technique involving the use of cutting devices to permit a larger resection of the tissue over the muscularis propria. The major advantages of the technique in comparison with polypectomy and endoscopic mucosal resection are controllable resection size and shape and en bloc resection of a large lesion or a lesion with ulcerative findings. This technique is applied for the endoscopic treatment of epithelial neoplasms in the gastrointestinal tract from the pharynx to the rectum. Furthermore, some carcinoids and submucosal tumors in the gastrointestinal tract are treated by ESD. To determine the indication, two aspects should be considered. The first is a little likelihood of lymph node metastasis and the second is the technical resectability. In this review, practical guidelines of ESD for the gastrointestinal neoplasms are discussed based on the evidence found in the literature.

Optimal band imaging system can facilitate detection of changes in depressed-type early gastric cancer

BACKGROUND

The endoscopic diagnosis of depressed-type early gastric cancers is difficult because these cancers manifest as subtle changes in color and shape. The newly developed optimal band imaging (OBI) system can reconstruct the best spectral images derived from ordinary endoscopic images and enhances the mucosal surface without the use of dyes. This imaging technique is based on narrowing the bandwidth of conventional image arithmetically by using spectral estimation technology.

OBJECTIVE

Evaluation of the usefulness of the OBI system for identifying the demarcation line of depressed-type early gastric cancers.

DESIGN

Prospective study.

SETTING

Jichi Medical University in Japan.

PATIENTS

Twenty-seven cases with depressed-type early gastric cancer.

MAIN OUTCOME MEASUREMENT

Comparative study for the success rate of identifying the demarcation line of depressed-type early gastric cancer by using optimal band images and conventional endoscopic images.

RESULTS

Demarcation of the depressed-type early gastric cancer was easily identified by optimal band images without magnification in 26 of 27 cases (96%), because distinct demarcation was observed endoscopically between the reddish images of the cancerous lesion and the yellowish images of the surrounding noncancerous area. With 40-fold magnification of optimal band images, the demarcation was also clearly recognized in all cases. Medical students could point out the demarcation line with significantly greater accuracy by observing the new nonmagnified optimal band images than by the conventional images (P< .0001).

LIMITATION

Small sample size.

CONCLUSIONS

The new contrasting images of the OBI system can delineate the depressed-type early gastric cancer more easily than conventional endoscopy.