Prognostic value of nucleolar organizer regions and DNA ploidy in gastric-cancer

The prognostic value of nucleolar organizer region (Ag-NOR) and ploidy status in 233 gastric cancer was determined. In addition, correlation of bromodeoxyuridine labeling indices (BrdU LIs) and Ag-NOR scores was studied. The proportion of Ag-NOR scores varied from 1.85 to 12.0 (mean, 3.6; S.D., 1.9). A significant correlation was found between Ag-NOR scores and BrdU LIs, tumor size, serosal invasion, and lymph node metastasis. By univariate analysis, Ag-NOR score was proved to be a significant prognostic indicator. However, Cox regression analysis revealed that Ag-NOR scores and DNA ploidy were not independent prognostic parameters. However, when the combination analysis of Ag-NOR scores and DNA ploidy was entered into the Cox model, this parameter emerged as an independent prognostic parameter. These studies indicate that Ag-NOR scores reflect proliferative activity of gastric cancer, and that the Ag-NOR scores may possibly be useful prognostic parameters, when combined with DNA ploidy.