Comparison of chromoendoscopy and conventional endoscopy in the detection of premalignant gastric lesions

Diagnosis and localization of intestinal metaplasia and early gastric cancer is problematic because of the lack of any telltale gross endoscopic signs.

To compare the efficacy of chromoendoscopy with conventional endoscopy for the detection of gastric premalignant lesions (intestinal metaplasia).

Thirty-three patients in whom previous routine endoscopic biopsies showed intestinal metaplasia were enrolled in a prospective study. Each patient underwent a two-step endoscopy procedure: conventional endoscopy and chromoendoscopy using methylene blue. Biopsies were taken during each step and were studied by an expert pathologist. Presence of intestinal metaplasia was considered a positive result.

Considering the presence of intestinal metaplasia anywhere in the stomach as a positive result, 13 patients were diagnosed with intestinal metaplasia using both endoscopic methods, while eight patients had positive results using chromoendoscopy without any metaplastic changes detected with the conventional method (P=0.003). One patient showed positive biopsies with the conventional method while the pathology report showed no positive biopsies using the chromoendoscopy method. The number of positive biopsies from the antrum, body and fundus were 18, 15 and seven, respectively, using chromoendoscopy, and 10, four and two, respectively, from the same sites using conventional endoscopy.

The present study demonstrated that chromoendoscopy is superior to conventional endoscopy for the detection of metaplastic changes and its use can be suggested for the screening of early malignancies of the stomach.