[Incidence and prevalence of digestive system tumors in Italy: estimates from mortality data]

This work presents estimates and middle-term projections of incidence and prevalence levels in Italy for cancers of the oral cavity and pharynx, of the stomach, and of colon and rectum. The estimation procedure was previously validated using incidence data observed by Italian cancer registries operating in limited geographical areas. Projections up to the year 2000 of mortality, incidence, and prevalence rates and estimated cohort effects are reported for stomach and colorectal cancers only. For both cancer sites, cohort effects, rather than period effects, result to be responsible for mortality and incidence dynamics. Incidence levels show a general decreasing trend for stomach cancer and an increasing one for colorectal cancer. Cumulative risk trend tends, however, to level-off for the youngest cohorts. Moreover, the well known geographical differences between the North and the South of the country seem to be progressively reducing.