N-nitroso compound precursors and gastric cancer: preliminary data of a study on a group of farm workers.

An epidemiological research on gstric cancer mortality rates carried out in the town of Forì is reported. The results are significant as regards the relation between the urban and rural areas, and show a higher risk for gastric cancer in the rural area. Salivary nitrite measurement in 92 farm workers showed particularly high values (over 30 ppm in 4 individuals). Analysis of histological findings in biopsies performed during endoscopy in 46 persons of the group studied showed a great number of CAG and CAG + IM in asymptomatic individuals.