Do We Need Multiple Biopsies for Assessing Gastric

Authors: Noriya Uedo

Publish Date: 2011/02/16

Volume: 56, Issue: 4, Pages: 926-928

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Abstract

It is widely accepted that differentiatedtype gastric cancers evolve through a multistep process starting with Helicobacter pyloriassociated superficial gastritis followed by atrophy intestinal metaplasia IM dysplasia and finally carcinoma 1 Thus the identification of such precancerous condition and followup 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 interobserver 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 ie 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 5The 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 7Although 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 pseudopylorization by stepwise biopsy across the endoscopic atrophic border When the atrophic border remained on the lesser curvature of the corpus the diagnosis was made as closedtype 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 opentype 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 largescale 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 carcinogenesisAhn et al 10 showed that mucosa in patients with opentype atrophic gastritis had more IM and Cdx2 overexpression compared to the mucosa in patients with closedtype atrophic gastritis implying that this was the reason that they were high risk for developing gastric cancer In this article they suggested that a considerable percentage of IM cases were diagnosed solely as opentype atrophic gastritis by endoscopic examination which might be underestimating the risk for development of gastric cancer Gastric mucosal atrophy and IM are basically different phenomena but they share a common process in development of Helicobacter pyloriassociated chronic atrophic gastritis and are usually present together Thus the main finding of their study is understandableHelicobacter pylori negative normal corpus mucosa Mucosa looked homogeneously reddish and the gastric folds were observed circumferentially in the gastric corpus a Color of the whole corpus mucosa appeared purple to dark green in AFI image b Magnifying image at the lesser curvature of the lower corpus white box in b showed small round pits with regularly arranged collecting venule CV c Biopsy specimen from the corpus lesser curvature had mild inflammatory cell infiltration but no atrophy and no intestinal metaplasia HE ×50 d Closedtype atrophic gastritis mucosa Whitish mucosa with increased visibility of vessel was seen in the lesser curvature of the corpus and in gastric folds were absent at that area e That area appeared green in AFI image f Magnifying NBI image of the green mucosa in the corpus lesser curvature white box in f showed ridge/villous surface structure with light blue crest LBC yellow arrow head g Biopsy specimen from the corpus lesser curvature had moderate inflammatory cell infiltration atrophy and intestinal metaplasia HE ×50 hThus taking all of these observations into consideration I would like to raise a question from the perspective of a practical endoscopist Do we need to take many biopsy specimens for assessing gastric cancer risk in patients receiving routine EGD I think the answer is “no” If we can establish the diagnostic method of endoscopy that corresponds well to histological atrophy or IM and relate the endoscopic findings to the substantial gastric cancer risk endoscopy should be enough to assess a risk for development of gastric cancer 15 Primary screening tests such as H pylori antibody serum pepsinogen family history etc may be enough to decide whether or not to perform endoscopy and we could diagnose the presence and grade of chronic atrophic gastritis and adopt an optimum surveillance program according to stratified risk by endoscopic findings Histologic findings must increase diagnostic yield of endoscopy to detect gastric cancers at an early stage

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