Helicobacter pylori infection in patients with early gastric cancer by the endoscopic phenol red test

Abstract

Background - An endoscopic procedure that uses a pH indicator called phenol red to assess Helicobacter pylori infected gastric mucosa has recently been developed. This test makes it possible to take biopsy specimens from H pylori infected areas. Aim - This test was applied to patients with early gastric cancers to clarify the role of H pylori in gastric carcinogenesis. Subjects - Sixty five patients with early gastric cancer (50 with differentiated adenocarcinoma and 15 with undifferentiated adenocarcinoma). Methods - Patients with early gastric cancer underwent the endoscopic phenol red test before their operation. In this test, areas infected with H pylori can be observed as 'coloured' areas where phenol red was turned from yellow to red. Results - H pylori infection was significantly (p < 0.001) more frequent in patients with differentiated adenocarcinomas than in those with undifferentiated adenocarcinomas. Differentiated adenocarcinomas were usually located in areas of mucosa infected with H pylori, but undifferentiated adenocarcinomas were frequently located in non-infected areas. Conclusion - H pylori may be a strong risk factor for differentiated early gastric cancer.