RISING INCIDENCE OF PANCREATIC-CARCINOMA IN MIDDLE-AGED AND OLDER WOMEN - TIME TRENDS 1961-90 IN THE CITY OF MALMO, SWEDEN

The city of Malmo (population 230 000), situated in the south of Swede n, is in an area which has the highest incidence of pancreatic cancer in the country. The present study was designed to assess time trends o f the incidence of pancreatic cancer 1961-90. The 1314 incident cases, 651 men and 663 women, were retrieved from the Regional Tumour Regist er and the National Cause-of-Death Register. In 75% of cases diagnosis was based on autopsy. Twenty per cent of these cases were first found at autopsy, being undiagnosed. The average age-standardised incidence was 20.4 per 10(5) person-years for men and 13.7 for women. The incid ence was higher for men than for women in all age groups above 44 year s. No change in incidence over time was observed for men. In older and middle-aged women there was however a statistically significant incre ase. The average relative change in women above age 64 was 1.7% per ye ar after age adjustment and in women aged 55-64 years 2.6% per year. W e have found no results indicating that this increasing incidence coul d be caused by detection bias as a result of changing autopsy rates du ring the study period and hence conclude that the observed increase is explained by a growing number of women being exposed to factors with a potential tumour-promoting or -initiating effect.