Relation of H pylori infection to upper GI tract conditions Relation of H pylori infection to upper GI tract conditions. The figure shows that most patients with gastroduodenal ulcers or gastric lymphoma or adenocarcinoma have also been infected with H pylori. Note, however, that the circles are not to scale, because gastric cancer occurs in less than 1% of those infected with H pylori. Note, too, that relationships among the different conditions are more complex than depicted. Despite that patients with cancer often have a prior history of ulcers, as shown in Figure 13–19, patients with a history of H pylori infection (that causes ulcers) are less likely to develop cancer. (Redrawn, with permission, from Calam J et al. Pathophysiology of duodenal and gastric ulcer and gastric cancer. BMJ. 2001;323:980.) Source: Gastrointestinal Disease, Pathophysiology of Disease: An Introduction to Clinical Medicine, 7e Citation: Hammer GD, McPhee SJ. Pathophysiology of Disease: An Introduction to Clinical Medicine, 7e; 2013 Available at: http://accesspharmacy.mhmedical.com/DownloadImage.aspx?image=/data/books/961/ham007_fig_13-18.gif&sec=53631011&BookID=961&ChapterSecID=53555694&imagename= Accessed: October 21, 2017 Copyright © 2017 McGraw-Hill Education. All rights reserved