Reported differences in clinicopathological patterns of early gastric carcinoma (GC) between the West and Japan suggest the presence of changes in cancer biology. The aim of this study was to analyze clinopathological-changing patterns of early gastric cancer (GC) biology in a large series of patients from Japan, where mortality rates for GC are high. Using the collected data of 1005 early GC patients treated surgically between 1975 and 2000, we analyzed differences in clinicopathological patterns for five consecutive periods: 1975-80 (group I), 1981-1985 (group II), 1986-1990 (group III), 1991-1995 (group IV), and 1996-2000 (group V). The mean age of the patients was 58 years (range, 21-88), which increased from 57 years (range 32-78), 55 years (21-78), 57 years (range 28-86), 58 years (range 24-87), and 60 years (range 32-84) in groups I, II, III, IV, and V, respectively (group II vs. IV, p<0.05). Analysis revealed differences in histological type (differentiated vs. undifferentiated adenocarcinoma in male and female) between groups; no tendency to decrease or increase was observed in either histological type in men, whereas a significant trend toward increasing of undifferentiated type and decreasing incidence of differentiated type was observed in women (p<0.05). The number of female patients with poorly differentiated adenocarcinoma increased from 50% to 69.7% over the period of the study. The patterns of GC location, macroscopic type, condition of lymph node metastasis and gender have no changed during the analyzed period of time, while those of GC histology, aging changed.
View full abstract