[The nucleolar organizer region in malignant non-Hodgkin's lymphoma].

Nucleolar organizer region-associated proteins (AgNORs) have been studied in parafin sections of 15 non-Hodgkin's lymphomas by a silver staining technique. On the basis of the Working Formulation of malignant non-Hodgkin's lymphomas all studied cases were divided into three groups. A statistically significant difference was found between number of AgNORs in the nuclei of low-grade lymphomas (mean 2.654 per nucleus), and also between intermediate-grade (mean 1.588 per nucleus) and high-grade malignant lymphomas. Significant difference was also observed between AgNOR area in high-grade and low-grade malignant lymphomas and between high-grade and intermediate-grade malignant lymphomas. However no statistically significant differences between all three studied groups with regard to the size of nucleus were found. It is suggested that this method can be very useful in the diagnosis of malignant non-Hodgkin's lymphomas.