Categorized: Gastroenterology
Help us help you! A Practical Approach to Biopsying the GI Tract (Part 1)
Part 1—Upper GI tract
Optimal biopsy sampling will help your expert Inform Diagnostics GI Pathologist to render a specific and accurate diagnosis. In the gastrointestinal tract, it is often important to sample normal-appearing as well as abnormal-appearing mucosa, as many disorders are histologically patchy. In addition, the endoscopic appearance may not correlate with histologic findings (marked Helicobacter gastritis may appear endoscopically normal). The outline below summarizes the biopsies that we recommend taking to allow us to provide you with the most clinically useful diagnostic information.
Esophagus
Suspected eosinophilic esophagitis: Biopsies of the lower esophagus and middle esophagus (and/or upper esophagus), submitted in separately labeled jars. Separate samples are needed because severe reflux in the distal esophagus can appear histologically identical to eosinophilic esophagitis. Two to four samples should be taken from each site regardless of the endoscopic appearance since the eosinophilic infiltrate in this disorder is often patchy.
Barrett’s dysplasia surveillance: Four-quadrant biopsies of every 2 cm of Barrett’s mucosa (every 1 cm if there is a history of high-grade dysplasia). Also, additional sampling of any endoscopically visible abnormalities (e.g. nodular or polypoid mucosa) is recommended, and these biopsies should be submitted separately from the routine surveillance biopsies.
Stomach
Possible or suspected gastritis: We advocate performing four biopsies, which should include two biopsies from the antrum (taken 2–3 cm proximal to the pylorus) and two biopsies from the body. This will allow for optimal detection of H. pylori and, in most cases, for definitive classification of atrophic gastritis (autoimmune versus multifocal). These four biopsies should be submitted in two jars as follows: jar 1 = antrum x2; jar 2 = body x 2. This method is similar to the updated Sydney protocol, the only difference being that we do not advocate biopsying the incisura angularis as a recent Inform Diagnostics study[1] revealed that biopsies of this site yield minimal additional diagnostic information.
Stomach lesion (e.g. tumor/mass, polyp, or ulcer): Biopsy/excision of the lesion, submitted in its own jar(s), PLUS the four biopsies described above (submitted in two additional jars). Most gastric lesions arise in a background of chronic gastric mucosal injury, and classifying any such process will allow for proper treatment and surveillance (e.g. intestinal metaplasia) as indicated.
Duodenum
Evaluation for celiac disease: To best evaluate for celiac disease, four biopsies of the duodenum are recommended, including one from the bulb. We recommend submitting the bulbar biopsy in a separate jar, as peptic-type injury can disrupt the histology at this site. However, it is NOT recommended that this site be “skipped” in a celiac disease workup, as the bulb may be the site that best demonstrates histologic features of celiac sprue.
References
1 Lash JG, Genta RM. Adherence to the Sydney System guidelines increases the detection of Helicobacter gastritis and intestinal metaplasia in 400,738 sets of gastric biopsies. Aliment Pharmacol Therapy 2013;38:424-431.
2 Lash RH, Taylor SL, and Genta RM. Optimal tissue sampling: the pathologist’s perspective. In: Weinstein WM, Hawkey CH, and Bosch J, eds. Textbook of Clinical Gastroenterology and Hepatology. Mosby:Chapter 144;2012.
