480 cases of advanced gastric carcinoma are classified according to Laurén or WHO and correlated to age and sex of the patients. The modal value of the incidence for age of the mucinous histologic type is 61-65 years for the men and 71-75 years for the women, while in the signet ring cell histologic type is 50 years in both sexes. These relationship, obtained only by the WHO classification, suggest that mucinous and signet ring cell type constitute distinct histoepidemiological entities.