In order to document any modifications in age and sex distributions, tumor locations and histological types, a retrospective study was performed comparing 377 consecutive cases of gastric cancers observed from 1942 to 1956 with 359 cases diagnosed from 1986 to 1987. The mean age at diagnosis rose from 57 to 66 years with no significant male/female ratio variations (1.6 vs 1.7). Tumors located in the proximal stomach increased from 13 to 23% (p less than 0.001) whereas those arising in the distal stomach decreased from 66 to 50% (p less than 0.001). Intestinal type gastric carcinoma decreased from 65.6 to 52.6% (p less than 0.001). The diffuse type rose from 24 to 43% (p less than 0.001) and the mucoid type fell from 10.3 to 4.4% (p less than 0.001). In spite of the overall decline in intestinal type carcinomas, this form remained more common in the upper third area and increased from 55 to 70% (p less than 0.001). Significant modifications in the distribution of diffuse, mucoid and signet ring cell type carcinomas were also noted. The possible significance and implications of these observations are discussed.