Gastric Cancer Rate Should Drop Significantly

ROTTERDAM, The Netherlands -- The incidence of gastric cancer in developed Western nations will decrease by 24% during the next 10 years, investigators have concluded.

The encouraging outlook is based on data showing a 15-year decline in rates of premalignant gastric lesions, A. C. de Vries, M.D., of Erasmus University, here, and colleagues reported online ahead of publication in the September issue of Gut.

From 1991 through 2005, the incidence of atrophic gastritis declined by 8.2% annually, dysplasia by 8.1% a year, and intestinal metaplasia by 2.9% a year in men and 2.4% in women.

The presumed cause, the authors speculated, are the declining rates of Helicobacter pylori infection.

"Based on our findings, a decline of approximately 24% may be expected within the coming 10 years," the authors concluded.

Worldwide, gastric cancer is the fourth most common cancer and accounts for the second largest number of cancer-related deaths. Currently, the worldwide incidence stands at 16.2/100,000 person-years.

Gastric carcinogenesis has a strong association with H. pylori infection, the prevalence of which has declined significantly in Western countries in the past few decades, paralleling a decline in rates of gastric cancer. But little is known about recent epidemiologic trends in premalignant gastric lesions, which are relevant to prognostication of gastric cancer incidence.

To fill that knowledge gap, Dr. de Vries and colleagues sought to identify patients with a first diagnosis of atrophic gastritis, gastric dysplasia, or intestinal metaplasia from 1991 through 2005 using the Dutch nationwide histopathology registry.

They found 23,278 patients with newly diagnosed atrophic gastritis, 8,517 with gastric dysplasia, and 65,937 with intestinal metaplasia. All of the diagnoses were documented by gastric biopsy.

Overall, the number of new diagnoses of atrophic gastritis and gastric dysplasia decreased by more than 8% per year in men and women, the researchers found.

The number of intestinal metaplasia diagnoses decreased in both sexes but was slightly greater in men than in women.

After 1996, the magnitude of decline increased for atrophic gastritis and intestinal metaplasia.

In acknowledging the study's limitations, the authors noted that the results apply only to patients who undergo gastric biopsy and should not be extrapolated to the general population.

Changing trends in pathologic assessment of biopsy tissue might also have influenced the results, they noted. However, they pointed out that intestinal metaplasia is a "relatively straightforward diagnosis not affected by changing histologic definitions," suggesting that other factors contributed to the decline in premalignant gastric lesions.

The authors also stated that prevalence differences between the study population and the general population are likely small, such that "trend, period, and cohort patterns observed here do reflect incidence patterns in general."