[Incidence of digestive system neoplasms. Trends. Soria 1981-1990]

The aim of this study was to evaluate, to compare and to identify the various incidence rate trends in digestive tract malignant tumours in the province of Soria. Tumor sites and histological types, patient's age, sex and town and area residence were studied. All new cases of digestive tract malignant tumours were collected during the 1981-1990 period. 30.4% of all malignant tumours in men (1906 patients) and 29% in women (1,256 patients) came from digestive tract sites. Incidence rates for each site were calculated for the two 1981-1985 and 1986-1990 subperiods. The histology, rates and trends of the tumours were compared with the other national and international cancer registries. Gastric cancer showed the highest adjusted rate for men (35.1 x 10(5) and colo-rectal cancer one for women (14.7 x 10(5). The lowest rates were for men in the gallbladder (0.5) and liver (1.1) sites; and for women in the gallbladder (1.6), whose diminishing trend was significant (2.92/0.75) (p < 0.05) and liver (0.5). Colorectal cancer showed a marked increase between the two subperiods for both sexes (men: 13.1/27.6) (women: 9.8/19.2). Pancreas cancer trends ascended for both sexes (men: 1.22/2.74) (women: 0.13/1.46). Gastric cancer rates in Soria are higher than the rest of the cancer registries in Spain while gallbladder, liver, and colorectal, cancer rates are one of the lowest for both sexes. Trends are significantly increasing in colorectal sites for both sexes (p < 0.01), and for women only in the pancreas (p < 0.05). The other cancer rate sites showed lesser variations and are not statistically significant.