Descriptive epidemiology of early and advanced gastric cancer in Ticino, Switzerland, with special emphasis on time trends.

BACKGROUND

The main purpose of the study was to describe early gastric cancer (EGC) epidemiology in the population of Ticino, Switzerland (about 280,000 inhabitants) over the period 1981-1990, as compared with the epidemiology of overall gastric cancer (GC).

PATIENTS AND METHODS

Incidence data were derived from the diagnosis data-file of the Cantonal Institute of Pathology. Numbers of certified deaths were abstracted from the registries of the Swiss Federal Office of Statistics.

RESULTS

The age-standardized (world population) incidence was 1.6/100,000 males and 0.7/100,000 females for EGC (sex ratio: 2.3) and 19.8/100,000 males and 9.1/100,000 females for GC (sex ratio: 2.2). Age- and sex-specific incidence rates for GC and for EGC showed similar distribution patterns. Mortality rates from GC declined over the period considered by about 20% in both sexes, while incidence rates decreased by only about 7%, suggesting diminished lethality. There was a slight increase in EGC incidence, which was restricted to men younger than 65 years and women older than 64 years.

CONCLUSIONS

EGC incidence rates were less than 10% of advanced gastric cancer incidence rates for both sexes and most age groups. Early and advanced gastric cancer had similar age and sex distributions. The downward trend in GC lethality over 1981-1990 was not entirely explained by the increase in the incidence of EGC.