[A study of DNA heterogeneity on gastric cancer with serosal invasive exposure].

In order to assess clinical significance, the DNA content in gastric cancer with serosal invasive exposure from 50 patients was determined by flow cytometry. The DNA histograms could be measured in two different vertical portions, on the mucosal and serosal sides. DNA heterogeneity was found in 15 patients (30.0%). These cases were divided into 4 groups according to the combination of DNA ploidy patterns. There were no significant differences in clinicopathological characteristics or survival rate between these 4 subgroups. Furthermore, the serosal invasion index (SII) defined as the ratio of serosal extent to mucosal extent was examined to determine the malignancy potential. All cases were divided into 2 groups, high SII and low SII, according to the value of SII. The survival rate was significantly lower in the high SII-aneuploid group compared with the low SII-diploid group. These results suggested that DNA analysis, subclassified by the serosal invasion index, is useful for assessment of the patient's prognosis.