[Nucleolar organizer regions and mitotic activity in non-Hodgkin's lymphoma]

Evaluation of nucleolar organizer regions (Ag-NOR) and mitotic regimen (MR) of normal lymph nodes and those with follicular hyperplasia (n = 10) as well as non-Hodgkin's lymphomas (NHL) of low and high grade of malignancy (n = 40) is performed in 50 cytograms stained after Pappenheim and with colloidal silver. Correlation of indices of MR and Ag-NOR with morphologic grade of malignancy of NHL was found. For blastic forms of NHL higher Ag-NOR, lager number of mitoses and their pathologic forms are characteristic compared with cytic ones (8.59 +/- 3.15; 13.60 +/- 4.9/1000; 37.9% and 2.06 +/- 0.63; 2.10 +/- 2.45/1000; 23.8%, respectively, p < 0.001). Calculation of Ag-NOR allowed to distinguish NHL of low grade and high grade of malignancy containing 1.13 to 3.68 and 4.76 to 18.22 Ag-grains per nucleus, respectively (the difference is statistically significant). This is important for differential diagnosis of "small cell" types of the tumor. Significant correlation between the number of Ag-NOR and mitotic activity of NHL is found (r = 0.772; p < 0.001) indicating that the number of Ag-NOR reflects cell kinetics of the tumor. The results of the activity evaluation of Ag-NOR and MR of cells may be used in differential diagnosis, gradation and definition of proliferative NHL status.