DNA CONTENT AND EXPRESSION OF PCNA AND P53 IN HODGKINS-DISEASE AND HODGKINS-LIKE B-CELL LYMPHOMA

DNA ploidy (by image cytometry) and expression of proliferating cell nuclear antigen (PCNA) and p53 tumor suppressor gene product (by immunohistochemistry) were investigated in 15 cases of Hodgkin's disease (HD) and 12 cases of HD-like B-cell lymphoma (HD-like NHL). Reed-Sternberg (RS) cells and their variants were DNA aneuploid in all cases. However, the fraction of hyperoctaploid tumor cells was higher in HD than in HD-like NHL. PCNA expression was high in neoplastic cells (>50%) and variable (5-40%) in reactive lymphocytes in both HD and HD-like NHL. p53 positivity was found in RS cells and their variants in 64% of HD cases, but only in 25% of cases of HD-like NHL. Our results support the suggestion that HD-like B-cell lymphomas should be considered as highly malignant non-Hodgkin's lymphomas rather than Hodgkin's disease.