Nuclear ultrastructure in low and high grade Non-Hodgkin's Lymphomas

ABSTRACT

Transmission electron microscopy was used to study the ultrastructure of nucleoli in 3 high and 3 low grade non-Hodgkin's lymphomas. Nucleoli with a single large fibrillar center were predominantly seen in the low grade group. While, the majority of nucleoli in high grade lesions contained several small fibrillar centers of approximately equal size. A third type of nucleolus appearance was identified with a large central fibrillar center surrounded by numerous small "satellite" fibrillar center. This nucleolus configuration was the least common but was more often seen in low grade than in high grade lymphomas. These results showed that fibrillar center size and morphology correlates with grade of non-Hodgkin's lymphoma and may reflect differences in ribosomal deoxyribonucleic acid transcription