Noriya Uedo

Quantitative analysis of the color change after iodine staining for diagnosing esophageal high-grade intraepithelial neoplasia and invasive cancer

BACKGROUNDnDespite its high sensitivity for detecting esophageal cancer, chromoendoscopy with iodine staining has low specificity and requires many biopsy specimens, which is undesirable. Dramatic color change after iodine staining (initially whitish yellow and then pink 2 to 3 minutes later) has come to be recognized as the pink-color sign in cancerous lesions.nnnOBJECTIVEnThe aim of the present study was to verify the accuracy of the pink-color sign for diagnosing esophageal squamous neoplasms by a quantitative analysis.nnnDESIGNnA quantitative analysis of endoscopic images was performed by using prospectively pooled data.nnnSETTINGnA cancer referral center.nnnPATIENTSnFrom December 2003 to September 2005, consecutive patients who underwent a procedure by an experienced endoscopist and had iodine-unstained lesions measuring 5 to 20 mm in diameter without obvious protrusions or ulcers were prospectively enrolled.nnnMAIN OUTCOME MEASUREMENTSnThe diagnostic ability of the quantitative assessment of the color change at 2 minutes after iodine staining (late phase) was investigated by using a receiver operating characteristic analysis.nnnRESULTSnA total of 45 iodine-unstained lesions in 32 patients were included in the study. Among these, 22 of 23 pink-color-positive lesions were diagnosed as high-grade intraepithelial neoplasias or invasive cancers, whereas 19 of 22 pink-color-negative lesions were diagnosed as nonneoplastic lesions or low-grade intraepithelial neoplasias. The area under the receiver operating characteristic curve was 0.94, indicating excellent validity of the test. A sensitivity of 88% and specificity of 95% were obtained.nnnLIMITATIONSnSingle-center retrospective analysis.nnnCONCLUSIONSnWe verified the accuracy of the pink-color sign for diagnosing esophageal squamous neoplasms by a quantitative analysis.

Do We Need Multiple Biopsies for Assessing Gastric Cancer Risk

It is widely accepted that differentiated-type gastric cancers evolve through a multistep process starting with Helicobacter pylori-associated superficial gastritis, followed by atrophy, intestinal metaplasia (IM), dysplasia, and finally carcinoma [1]. Thus, the identification of such precancerous condition and follow-up of patients in whom they are found could lead to the diagnosis of gastric cancer at early stage and improved patient survival. However, diagnosis of atrophy and IM by conventional white light endoscopy has high inter-observer variability [2] and a poor correlation with histological findings [3]. Consequently, the diagnosis of atrophy or IM is currently based on histology of biopsy specimens from certain anatomic locations of the gastric mucosa, i.e., the updated Sydney system [4]. This system recommends taking at least five biopsy specimens (two from the antrum, two from the corpus and one from the incisura angularis) to grade severity of neutrophils (activity) and lymphocytic infiltration (inflammation), glandular atrophy (atrophy), and intestinal metaplasia. A recent Western publication proposes a staging system to classify gastric cancer risk in clinical practice on the basis of the histological findings of multiple biopsies [5]. The reason for taking biopsies from multiple sites in the stomach is that the grade and distribution of gastritis are different at each site of the stomach in a patient with chronic atrophic gastritis. Mapping studies of biopsy findings suggested that chronic atrophic gastritis develops from the lesser curvature of the lower gastric body and extends upward and laterally in the corpus [6]; therefore, knowledge of the biopsy site is important to interpret histological finding of gastritis in multiple biopsy specimens. When we investigated association between gastric cancer risk and histological grade of gastritis at the each biopsy site in the stomach, the presence of IM in the lesser curvature of the corpus had the strongest association with cancer risk among other findings of gastritis in the other sites [7]. Although gastritis is regarded as a histological entity, many attempts have been made to diagnose the disease macroscopically during esophagogastroduodenoscopy (EGD). Kimura et al. [8] suggested that the endoscopic finding of atrophic mucosa was pale yellowish mucosa with increased mucosal vessel visibility, indicating that it was related to histological finding of atrophy of fundic gland (pseudo-pylorization) by step-wise biopsy across the endoscopic atrophic border. When the atrophic border remained on the lesser curvature of the corpus, the diagnosis was made as closed-type atrophic gastritis (antral predominant gastritis), whereas when the atrophic border no longer exists on the lesser curvature and extends along the anterior and posterior walls of the stomach, the diagnosis was made as open-type atrophic gastritis (pangastritis or corpus predominant gastritis). This endoscopic diagnostic criterion is commonly accepted and practically used for the diagnosis of chronic atrophic gastritis in Japan. Actually, Uemura et al. [9] indicated that extent of mucosal atrophy diagnosed by endoscopy was associated with risk for development of gastric cancer in a large-scale cohort study. In contrast to point evaluation of gastritis by biopsy, endoscopy is advantageous to evaluate the actual extent and distribution of atrophy or IM in the gastric mucosa that is related to gastric carcinogenesis. Ahn et al. [10] showed that mucosa in patients with open-type atrophic gastritis had more IM and Cdx2 N. Uedo (&) Department of Gastrointestinal Oncologym, Endoscopic Training and Learning Center, Osaka Medical Center for Cancer and Cardiovascular Diseases, 3-3 Nakamichi 1-chome, Higashinari-ku, Osaka 537-8511, Japan e-mail: uedou-no@mc.pref.osaka.jp

Endoscopic tri-modal imaging improves detection of gastric intestinal metaplasia among a high-risk patient population in Singapore

BackgroundDetection of pre-neoplastic gastric mucosal changes and early gastric cancer (EGC) by white-light endoscopy (WLE) is often difficult. In this study we investigated whether combined autofluorescence imaging (AFI) and narrow band imaging (NBI) can improve detection of pre-neoplastic lesions and early gastric cancer in high-risk patients.Patients and MethodsChinese patients who were 50-years-old or above with dyspepsia were examined by both high-resolution WLE and combined AFI followed by NBI (AFI–NBI), consecutively in a prospective randomized cross-over setting, by two experienced endoscopists. The primary outcome was diagnostic ability of the two methods for patients with pre-neoplastic lesions such as intestinal metaplasia (IM) and mucosal atrophy.ResultsSixty-five patients were recruited. One patient with large advanced gastric cancer was found and excluded from the analysis. Among the remaining 64 patients, 38 (59xa0%) had IM; of these, 26 (68xa0%) were correctly identified by AFI–NBI (sensitivity 68xa0%, specificity 23xa0%) and only 13 (34xa0%) by WLE (sensitivity 34xa0%, specificity 65xa0%). AFI–NBI detected more patients with IM than did WLE (pxa0=xa00.011). Thirty-one patients (48xa0%) had mucosal atrophy. Ten patients (32xa0%) were identified by AFI–NBI (sensitivity 32xa0%, specificity 79xa0%) and four patients (13xa0%) by WLE (sensitivity 13xa0%, specificity 88xa0%) (pxa0=xa00.100). No dysplasia or EGC was found.ConclusionAFI–NBI identified significantly more patients with IM than did WLE. Our result warrants further studies to define the role of combined AFI–NBI endoscopy for detection of precancerous conditions.

Autofluorescence Imaging Video-Endoscopy System for Diagnosis of Superficial Gastric Neoplasia

An autofluorescence imaging video-endoscopy system (AFI) produces real-time pseudocolor images from computed detection of autofluorescence emitted by endogenous fluorophores in the mucosa. In the AFI images of the gastric body, the fundic mucosa appears purple, whereas atrophic mucosa appear bright green. Gastric tumors appear purple or green in the AFI images according to their morphology, i.e., elevated or depressed, respectively. Therefore, the color patterns of gastric tumors are classified into four types: purple tumors in a green background, purple tumors in a purple background, green tumors in a green background, and green tumors in a purple background. Purple tumors in a green background and green tumors in a purple background are readily distinguished by their color. In contrast, purple tumors in a purple background are difficult to define by color. Green tumors in a green background appear similar in color to the surrounding mucosa, but the tumor extension can be determined by their purple rim. Diagnostic accuracy of AFI for tumor extension was better (68%) than that by white light endoscopy (36%), but was not as good as chromoendoscopy (91%). The low accuracy rate was mainly caused by interference of an ulceration or scar, while the AFI diagnosed flat tumor extension more accurately than did white light images. Because the AFI could visualize flat or isochromatic tumor extension compared with white light endoscopy, it detected more multiple neoplasia in patients who underwent endoscopic treatment.

Case of Superficial Esophageal Adenocarcinoma in Short-Segment Barrett's Esophagus

A 64-year-old man with a history of myocardial infarction presented with heartburn and abdominal fullness that he had had for a month. He visited a primary physician, and barium radiography and esophagogastroduodenoscopy revealed a tumor in the distal esophagus. He was referred to our institute for surgical treatment. Vital status and physical examination revealed no abnormality. Except a mild elevation of the fasting plasma glucose level, blood cell count, blood chemistries, and serum carcinoembryonie antigen (CEA) level were all normal.