ESTIMATION AND PROJECTIONS OF COLORECTAL-CANCER TRENDS IN ITALY

Background. Occurrence of and prognosis for tumours of the colon and r ectum are thought to be changing rapidly due to simultaneous changes i n risk factor prevalence, early diagnosis and treatment. In this paper time trends of morbidity, survival and mortality for colorectal cance r during the period 1970-1990 are estimated and analysed. Methods. Mor tality trends were obtained from official death certificates. Relative survival rates were computed from population-based cancer registries. Incidence and prevalence rates were estimated from mortality and surv ival data. Results. Incidence rates were increasing during the period considered, with a lower rate of increase for the youngest birth cohor ts. Relative survival rates of both colon and rectum cancers were high er for women, and for younger age groups, and were positively associat ed with period of diagnosis. No significant survival difference among the cancer registries used was found. A total of about 155 000 prevale nt cases, 40% of which had been diagnosed greater than or equal to 7 y ears before, were estimated in the Italian population for the year 199 0. Mortality rates were slightly increasing for men and stable for wom en, Projections of colorectal cancer trends to the year 2000 indicate major expected rises in both incidence and prevalence. Conclusion. Col orectal cancer represents a problem of growing impact far health servi ces in Italy. This conclusion can probably be extended to many develop ed countries.