Time trend in pancreatic cancer incidence in Connecticut, 1935-1990.

A total of 13,246 incident pancreatic cancer cases, reported to the Connecticut Tumor Registry between 1935 and 1990, were included in our study. Results indicate that the overall age-adjusted incidence rate of pancreatic cancer increased between 1935 and 1964 in males, and leveled off thereafter. Since 1975, the incidence rate has in fact been decreasing, from 12.04/100,000 in 1975-79 to 10.44/100,000 in 1985-90. In females, the overall age-adjusted incidence rate also increased between 1935 and 1974. Since then, however, it has remained relatively stable. Age-specific incidence rates also show no signs of an increase in rate from any age group, or from either sex for recent birth cohorts. There is also no clear increase in the incidence of pancreatic cancer in any of the ethnic/gender categories since the early 1970s. Age-period-cohort modeling shows that the increasing birth cohort trend peaked among those born around 1920-1925 and, for recent birth cohort, a slightly decreasing trend was observed in both males and females. Our study reveals no signs of an increase in the immediate future in pancreatic cancer incidence rate in any of the sex, ethnic and age groups in Connecticut.