Usefulness of magnifying endoscopy in the diagnosis of early gastric cancer

Characteristics of magnified endoscopic images of gastric extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue, including changes after treatment

BACKGROUND

The utility of magnifying endoscopy for diagnosis of epithelial tumors has been reported, but there are few reports for nonepithelial tumors.

OBJECTIVE

To determine the characteristics of magnified images of gastric extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) before and after treatment.

DESIGN

This was a retrospective study.

SETTING

Endoscopy Unit, Hokkaido University Hospital.

PATIENTS

Eleven patients diagnosed with MALT lymphoma were enrolled.

INTERVENTIONS

The microstructural pattern, collecting venules, and abnormal vessels in gastric MALT lymphoma were assessed before treatment and at 4 to 7 months after treatment by using magnifying endoscopy. MAIN OUTCOME MEASUREMENT AND RESULTS: The characteristics of magnified endoscopic images before treatment were the disappearance of gastric pits and the appearance of abnormal vessels. Ten cases of Helicobacter pylori-infected MALT lymphoma were treated by H. pylori eradication, and 1 H. pylori-negative case was treated by radiation therapy after eradication therapy. Ten patients achieved complete disease remission. After the treatment, recovery of gastric pits and subepithelial capillary network, and the disappearance of abnormal vessels were revealed by magnifying endoscopy.

LIMITATION

This was a small pilot study.

CONCLUSIONS

Magnified findings of gastric MALT lymphoma before and after therapy seem to correlate with complete response and no response.

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.

Diagnostic value of magnifying chromoendoscopy in gastric premalignant lesions

AIM: To evaluate diagnostic value of magnifying chromoendoscopy (MCE) in gastric premalignant lesions.

METHODS: Microstructures of gastric mucosa in 180 patients with gastric erosion were examined using magnifying endoscopy in combination with methylene blue staining. Magnifying endoscopic patterns of gastric erosion pits were classified into six types: type A (round spot pits), types B (short rod pits), type C (sparsely and thickly linear), type D (patchy), type E (villous) and type F (unclear or disappearances of pits or abnormal hyperplasia blood capillary). And the results of histopathological biopsy taken from gastric erosion were regarded as the gold standard.

RESULTS: Types A and type B were found in normal gastric mucosa, while types C, D, E, F were found in gastric mucosa with active inflammation, atrophic inflammation, intestinal metaplasia and dysplasia of variable degree respectively. Type E mucosa (81.8%) suggested intestinal metaplasia, type F indicated existence of dysplasia of variable degree (86.3%), and type F with abnormal hyperplasia blood capillary suggested dysplasia (89.9%).

CONCLUSION: Types of gastric pits could be accurately and effectively identified under magnifying chromoendoscopy and identification of type E and F would facilitate the diagnosis of such gastric premalignant lesions as intestinal metaplasia and dysplasia.

Single wavelength micro-endoscopy in non-surgical vascular lesion diagnosis & characterization

Malignant and dysplastic epithelial lesions have often been reported to excite vascular responses by histopathological characterization. Little is reported concerning in vivo real-time imaging of vascular patterns and flow in health or disease but the development of miniature imaging instrumentation has now allowed such developments. We describe the application of a selective wavelength (540 nm) epi-illumination Hopkins pattern endoscopic imaging system to image vascular tissues and capillary blood flow in vivo. The contrast mechanism in such imaging was characterized, haemoglobin acting as a chromatic transmission filter despite endoscopy being a non-invasive and therefore principally reflection mode imaging system. In vivo adrenergic vascular responses, capillary flow rate variations over time and variations in normal capillary architecture around the oral cavity were recorded; demonstrating that simple imaging systems can be used for non-surgical diagnosis and characterization of vascular lesions, tumours and treatment responses.

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.

Fluorescence diagnostics of Helicobacter pylori-infected human gastric mucosa: establishing technique and validity

OBJECTIVE

Bacterial factors, including strain type, anatomic distribution and density, and host responses are important determinants in the pathogenesis of erosive and neoplastic changes linked to gastric Helicobacter pylori (H. pylori) infection. The purpose of this study was to investigate the potential use of photodiagnostics in mapping H. pylori infection. The relationship between fluorescence in individual gastric pits of H. pylori(+) and H. pylori(-) subjects versus that in larger field views of the gastric mucosa and the use of fluorescence to determine H. pylori status in different gastric areas were studied.

MATERIAL AND METHODS

Antrum, corpus and fundus biopsies from 8 H. pylori(+) and 4 H. pylori(-) subjects taken during two gastroscopies were used for autofluorescence (535 nm excitation) and aminolevulinic acid (ALA)-induced protoporphyrin IX fluorescence (405 nm excitation) determinations.

RESULTS

In the antrum, corpus and fundus a close correlation between individual pit and full-field image (FFI) fluorescence was demonstrated for H. pylori status (R>0.85; R>0.75; R>0.80) and both excitation wavelengths (R>0.89; R>0.85; R>0.95), respectively. In the antrum, FFI in H. pylori(+) subjects exceeded that in H. pylori(-) subjects using 405 nm but not 535 nm excitation regardless of ALA treatment (p<or=0.026). In the corpus and fundus, fluorescence using 405 nm excitation was greater in H. pylori(+) than in H. pylori(-) subjects only after ALA treatment (p<0.00005, p=0.03). The ratio of 535 nm:405 nm-excited fluorescence decreased from the fundus>corpus>antrum for both H. pylori(+) and H. pylori(-) subjects regardless of ALA treatment (p=0.03).

CONCLUSIONS

Fluorescence-based identification of areas of H. pylori-infected gastric mucosa using 405 nm excitation combined with ALA treatment is feasible and, using a ratio of 535 nm:405 nm-excited fluorescence, it is possible to distinguish H. pylori status and the different areas of the stomach even without ALA.

Novel zoom endoscopy technique for diagnosis of small flat gastric cancer: a prospective, blind study

BACKGROUND & AIMS

During gastroscopy we frequently encounter flat reddened lesions in the stomach. Making a correct diagnosis of flat small early gastric cancer is dependent not on endoscopic diagnosis, but on histopathologic diagnosis of biopsy specimens alone. We investigated the diagnostic accuracy of magnified endoscopic findings for differentiating between reddened mucosa caused by gastritis and flat reddened gastric cancer, prospectively and blindly.

METHODS

A total of 603 consecutive patients were examined by upper-gastrointestinal zoom endoscopy and the prevalence of each of the following magnified endoscopic findings, which already had been reported as characteristic for differentiated carcinoma, was recorded: (1) presence of a demarcation line between the reddened lesion and the surrounding mucosa, (2) disappearance of the regular subepithelial capillary network pattern, and (3) presence of an irregular microvascular pattern within the flat reddened lesion. Patients with known gastric carcinomas were excluded from this study.

RESULTS

A total of 158 flat reddened lesions from 158 patients were detected. Pathologically, 144 flat reddened lesions showed only gastritis, whereas 14 lesions were newly diagnosed as carcinoma. Regarding diagnostic accuracy for carcinoma, the negative predictive values of the presence of a demarcation line and disappearance of the regular subepithelial capillary network pattern were 100% and 100%, respectively, and the diagnostic accuracy of the irregular microvascular pattern was 98.7%.

CONCLUSIONS

The novel zoom endoscopic findings based on microvascular architecture are very useful for making a differential diagnosis between flat early gastric carcinoma and gastritis.

Early diagnosis of early gastric cancer

The prognosis of gastric cancer is closely related to the stage of disease at diagnosis. Early gastric cancer, whereby disease is limited to mucosa and submucosa, confers a survival rate of greater than 90% in 5 years in many centres. Gastric cancer is still a major cause of cancer mortality worldwide. In high incidence areas such as Japan, screening of asymptomatic population has been advocated. However, in Western countries, mass screening is not cost-effective. Hence, strategy has been directed to screen symptomatic individuals who are at higher risk of gastric cancer. Most patients with early gastric cancer present with symptoms indistinguishable from benign peptic ulcer disease. Screening for this group of patients improves detection rate of early gastric cancer and therefore its prognosis. Endoscopy for surveillance of premalignant lesions has been explored with this objective in mind. Serology testing for biomarkers such as pepsinogen, anti-Helicobacter pylori antibody and gastrin has been studied as an alternative to endoscopy. There is compelling evidence for the role of H. pylori in the initiation of Correa's cascade (stepwise progression from chronic active gastritis, atrophic gastritis, intestinal metaplasia, dysplasia and finally adenocarcinoma). Regression of premalignant lesions has been demonstrated with H. pylori eradication. However, it is not known whether this might effectively prevent gastric cancer in either low or high-risk population.

Magnifying pharmacoendoscopy: response of microvessels to epinephrine stimulation in differentiated early gastric cancers

BACKGROUND

Magnifying endoscopy is a promising modality for fine observation of minute surface structures and microvessel architecture in gastric lesions.

OBJECTIVE

To observe the response of microvessels to epinephrine stimulation in early gastric cancer tissues and to assess the usefulness of magnifying pharmacoendoscopy for histologic diagnosis.

DESIGN

This was a prospective pilot study.

SETTING

This study was conducted at an academic hospital.

PATIENTS

Twenty-nine patients with differentiated early gastric cancer were enrolled.

INTERVENTIONS

Microvessels in both the cancerous lesion and its adjacent non-neoplastic gastric mucosa were observed by magnifying endoscopy before and after focal spray with epinephrine solution (0.05 mg/mL).

MAIN OUTCOME MEASUREMENTS AND RESULTS

After epinephrine stimulation, noncancerous gastric mucosa surrounding the cancerous lesion showed a change in color from red to white; no microvessels were evident. On the other hand, all the cancerous lesions examined clearly showed enhancement of tumor microvessels. The rate of detection of tumor microvessels by magnifying pharmacoendoscopy (100%) was significantly higher than that by magnifying endoscopy alone (41.3%).

LIMITATIONS

This was small pilot study.

CONCLUSIONS

Magnifying pharmacoendoscopy with epinephrine is a powerful tool for assessing tumor vascularity and may contribute to the histologic diagnosis of differentiated early gastric cancers before endoscopic treatment.

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

BACKGROUND

Changes to the mucosal surface of early gastric carcinomas and gastric adenomas as viewed by enhanced-magnification endoscopy with acetic acid have not been investigated thoroughly. Using this technology, we investigated the appearance of the gastric surface patterns of neoplastic and surrounding nonneoplastic mucosa.

METHODS

Forty-seven consecutive patients with early gastric carcinomas or gastric adenomas underwent enhanced-magnification endoscopy following 1.5% acetic acid instillation. All biopsy specimens were taken from the area at which the enhanced-magnified endoscopic image was obtained.

RESULTS

Surface patterns of gastric tumors and the surrounding mucosa were classified into five 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 arrangements and sizes of pattern types I, II and III; type V, destructive patterns of types I, II and III. The predominant pattern of the surrounding mucosa was type III, and most type III mucosa had characteristics of intestinal metaplasia. Although all elevated adenomas showed type II or type III surface patterns, both depressed adenomas showed type IV. Elevated carcinomas showed type III (42.9%) or type IV (57.1%) surface patterns, while depressed carcinomas showed type IV (70%) or type V (30%). Although differentiated tubular adenocarcinomas showed type III (10.3%), type IV (86.2%), or type V (3.5%) surface patterns, all of the signet-ring cell carcinomas and poorly differentiated tubular adenocarcinomas showed type V.

CONCLUSIONS

Enhanced-magnification endoscopy may be useful for identifying gastric tumors and determining the extent of horizontal spread, especially in tumors of the depressed type.

Interventional endoscopy

PURPOSE OF REVIEW

This review is an update of key issues in gastric interventional endoscopy. It focuses on the areas of patient preparation, endoscopic mucosal resection, gastroduodenal stenting, and endoscopic placement of enteric feeding tubes.

RECENT FINDINGS

Clopidogel (Plavix), a newer antiplatelet agent, can increase the risk of bleeding. Therefore, in selected cases, it should be held for 7-10 days prior to interventional procedures. In experienced hands, endoscopic mucosal resection (success rate, 76-100%; complication rate, 4-28%) and gastroduodenal stenting (success rate, 81-92%; complication rate, 1-17%) seem to be safe and effective techniques.

SUMMARY

The field of interventional endoscopy continues to advance and to conquer new frontiers. These advances create new problems that need to be addressed and studied by researchers, however. It is only through these types of reviews that our state of knowledge can be updated to help provide the latest information for clinicians in the field and to challenge researchers with future problems that need to be studied.

Identification of the thrombin light chain a as the single best mass for differentiation of gastric cancer patients from individuals with dyspepsia by proteome analysis

Gastric cancer mortality is second only to lung cancer, and its prognosis is dismal. Using surface-enhanced laser desorption/ionization-time-of-flight mass spectrometry, we previously identified a single best mass, which could separate gastric cancer from patients without cancer, with a sensitivity of 89.9% and a specificity of 90%. Using protein liquid chromatography systems with various chromatography media and MS/MS analysis, we were able to identify thrombin light chain A, a proteolytic fragment of prothrombin, as the single best mass for early detection of gastric cancer patients. These findings indicate that disturbances in the coagulation-system are early events in gastric cancer biology and that a decrease or loss of thrombin light chain A, which we termed negative serum protein profiling, may contribute to the diagnosis of cancer patients.

Direct visualization of intestinal villi by high-resolution magnifying upper endoscopy: a validation study

BACKGROUND

New generation videoendoscopes potentially may visualize duodenal villi. This study compared endoscopic findings with this type of instrument to the histopathologic evaluation of duodenal villi.

METHODS

A total of 191 patients underwent upper endoscopy for the purpose of obtaining duodenal biopsy specimens. The findings were assessed independently by 3 experienced observers by using a commercially available, high-resolution, high-magnifying (x2) videoendoscope. The duodenal villous profile was determined by endoscopic magnification and by endoscopic magnification after filling the duodenum with water. With both endoscopic magnification and endoscopic magnification after filling the duodenum with water, villous patterns were scored as the following: definitely present, partially present, or definitely absent. Villous patterns also were histopathologically scored as the following: normal, partial villous pattern, or total villous atrophy.

RESULTS

Interobserver variability was excellent (kappa = 0.93). The concordance between either endoscopic magnification or endoscopic magnification after filling the duodenum with water and histology was 100% for presence/absence of villi. The sensitivity, the specificity, and the positive and negative predictive values of endoscopic magnification for detection of any villous abnormality were 95%, 99%, 95%, and 99%, respectively; the respective values of endoscopic magnification after filling the duodenum with water were 95%, 98%, 92%, and 99%.

CONCLUSIONS

High-resolution magnifying upper endoscopy can reliably predict the presence or the absence of duodenal villi.