Trends in stomach and pancreatic cancer incidence and mortality in England and Wales, 1951-2000.

BACKGROUND

The aim of this study was to describe period and cohort effects in incidence and mortality of stomach and pancreatic cancer in England and Wales.

METHODS

National figures for mortality (1951-2000) and incidence (1971-2000) were analysed using log-linear Poisson regression models to obtain relative risks (RR) for period (year of incidence or death) and cohort (year of birth).

RESULTS

Stomach cancer shows a pronounced cohort effect in mortality with a decline in RR in men from 2.20 (1876) to 0.47 (1946) and a reduction from 2.79 to 0.41 for women. Mortality to incidence ratios are now less than 0.70. Pancreatic cancer mortality (men) RR rose from 0.91 (1951-1955) to a peak 1.11 (1976-1980) and then declined to 0.90 (1996-2000). Women showed a similar pattern. Cohort RR (men) increased to a peak of 1.14 in 1916 and declined to 1.01 in 1946, and continued to fall; the peak occurred slightly later in women. Mortality to incidence ratios were near 1 in the first 20 years, declining to 0.95 in the last 10 years.

CONCLUSION

Stomach cancer incidence has fallen continuously from 19(th) century birth cohorts onwards. Incidence of pancreatic cancer has fallen in successive birth cohorts after 1920; peak period risk was 1976-1990. Age-standardized mortality and case mortality for pancreatic cancer are declining.