Presupposition of malignancy grades in gastric cancer through DNA histogram pattern using imprinted malignant cells from biopsy samples

Abstract

Nuclear DNA of cells imprinted from preoperative biopsy samples, obtained from 125 patients with gastric cancer curative who subsequently underwent operation, was assessed by microspectrophotometry. DNA histogram patterns fell into 4 main categories: diploid type (I), aneuploid type (II), diploid predominant type (III), and aneuploid predominant type (IV): the later two categories being of mosaic type. These four types were further classified into four subtypes, all considered to be polyploid type over 5 c cells, which constituted more than 25% of the total cell count. The relation ship of these 8 types of cells to the progress of cancer, grade of invasion depth, lymphonodal metastasis, histological differentiation grade, and the prognosis of cancer, was analysed. The result of this analysis was that as the stage of gastric cancer progressed, that is, as the grade of invasion depth and lymphonodal metastasis increased, the incidence of poly ploidy cells increased. Cells from those patients with recurrent gastric cancer and/or from patients who died of gastric cancer, often were of aneuploid type. In poorly differentiated cancer, the incidence of aneuploidy or polyploidy increased as the stage of cancer progressed, but the incidence of diploidy on the whole, was high. Well-or moderately-differentiated cancer, early cancer, and cases with stage I cancer, had a high rate of diploid type cells. Howerver this rate was low, when compared with that of poorly differentiated cancer. The incidence of over 5 c cells in each case displayed an upward trend as the stage of gastric cancer progressed. Since it seems apparent that DNA histogram pattens have a relation ship to the stage, histological differentiation grade, and prognosis of gastric can cer, the results of these studies will constitute an index of malignancy grade in gastric cancer.