Cytometrically determined relative DNA content as an indicator of neoplasia in gastric lesions

Cellular samples from human gastric endoscopic biopsies were analysed in order to detect possible DNA content alterations as markers of cancerous and precancerous lesions of the digestive tract. Samples were derived from the stomach of normal donors (17 cases), and from patients clinically classified as affected by stomach adenocarcinoma (18 cases), chronic atrophic gastritis (20 cases), or other nonneoplastic lesions (17 cases). Sample processing was performed by mechanical and enzymatic treatment to obtain monodispersed cells. Staining for flow cytometric analysis was achieved with ethidium bromide and mithramycin. Samples from normal donors constantly exhibited a single cell population with diploid DNA content. All but three neoplastic specimens exhibited both a diploid and an aneuploid cell subpopulation, with the DNA index of the aneuploid peak ranging from 1.10 to 1.85 (except a single instance with a value of 3.13). The presence of a recognizable aneuploid subpopulation was also observed in 9 out of 20 chronic atrophic gastritis specimens. Such aneuploidy is similar to that observed for the adenocarcinoma, even if the fraction of aneuploid cells appears to be generally higher in the tumor than in the gastritis cases. All other cases of gastritis and of nonneoplastic disease exhibited diploid cells only. The meaning of aneuploidy in some gastritis specimens is a phenomenon not yet fully explained. Still, aneuploidy appears to be a useful marker for recognizing the presence of suspect malignant cells in gastric lesions.