ORLANDOResearchers from Kure, Japan, reported on the first
prospective study to show a direct connection between infection with Helicobacter
pylori and the onset of gastric cancer. Their work, presented at
the Digestive Disease Week meeting, builds upon epidemiologic
research done in the early 1990s that strongly suggested such an association.
The study involved 1,166 patients with gastric disease who were
tested for H pylori infection. The researchers took pains to
ensure the accuracy of all negative readings. Each patient underwent
three tests for the presence of H pylori: histology, a rapid
urease test, and a serologic test.
If all three tests were negative, we knew the patient was
negative for H pylori, Naami Uemara, MD, said in an
interview. Each test yields a false negative about 20% of the
time. With three tests in agreement, you eliminate false
negatives. Dr. Uemara, chief of gastroenterology at Kure Kyosai
Hospital, led the research team.
Of the total group, 246 were negative for H pylori while 920 were
positive. Patients who tested positive for H pylori had the
following diagnoses: chronic gastritis, (382 patients), active
gastric ulcer (186), active duodenal ulcer (180), gastric polyp (172).
All patients underwent endoscopy at least once every 2 years. Therapy
to eradicate H pylori was not employed in any of the patients.
The follow-up period ranged from 5 to 8.5 years, and averaged 7
Among patients free of H pylori, follow up endoscopy has revealed no
cases of gastric cancer. In contrast, at the time of this analysis,
the researchers had discovered gastric cancer in 17 of the 920
patients infected with H pylori (P < .05).
Histology revealed that 12 of the gastric cancers were of the
intestinal type, and 5 were of the diffuse type. This led us to
conclude that, in humans, H pylori-associated gastritis causes
the onset of both types of gastric cancer, Dr. Uemara