Mitotic index in gastric carcinoma of the scirrhous type.

For the purpose of studying the clinical and pathological specificities of the scirrhous type in gastric carcinoma, 96 patients with gastric carcinoma were studied according to age, sex, stage, macroscopic types and mitotic index. Scirrhous carcinoma was diagnosed in 45 patients. There were higher incidences of scirrhous carcinoma in the younger generation and among women. In the scirrhous type, the percentage of stages III and IV was higher than that of stages I and II (p less than 0.005). In Borrmann's categories III and IV, patients with the scirrhous type were more numerous than those with the other types. Mitotic indices were 18.4 +/- 8.1 in scirrhous type, 52.8 +/- 13.5 in medullary type, 54.1 +/- 16.9 in intermediate type and 53.3 +/- 11.5 in non-cancerous gastric mucosa. The low rate of mitotic index in those with scirrhous carcinoma was statistically significant compared to those of other types and that of the non-cancerous gastric mucosa (P less than 0.001). Mitotic index is apparently related to the extent and the degree of degeneration of interstitial connective tissue. The speed of the growth of the tumor mass in gastric carcinoma is not so closely related to the mitotic index, and relates to a greater extent the number of dissociated cells entering the digestive canal.