RELATION BETWEEN POPULATION-DENSITY AND CANCER INCIDENCE, ILLINOIS, 1986-1990

Many investigators have examined urbanization gradients in cancer rate s. The authors used incidence data for 1986 through 1990 from the Illi nois State Cancer Registry, a large, population-based incidence regist ry, to identify race-specific, urban-rural trends in cancer rates. Usi ng population density, they categorized an urbanization gradient into four groups. Five-year, average annual age-adjusted, site-specific inc idence rates were calculated for all sex-race strata within each popul ation density group. Monotonic and statistically significant cancer in cidence trends across all race-sex groups were found for cancers of th e esophagus, liver, lung, female breast and cervix, male prostate, ner vous system, non-Hodgkin's lymphomas, and all cancers combined. No tre nd was observed for blacks that was not also seen for whites; however, significant trends for cancer of the pancreas and Hodgkin's disease w ere seen for whites but not for blacks. Colon cancer in males was the only sex-specific trend in cancer that can occur in both sexes. Analyt ic studies for sites with consistent urban-rural trends across all rac e-sex groups may be fruitful in identifying the aspect of population d ensity, or other unmeasured factor, that contribute to these trends.