Diagnostic accuracy of imprint cytology in the assessment of Hodgkin's disease in Japan.

Our objective was to evaluate the usefulness of cytomorphologic assessment in the accuracy of diagnosis of Hodgkin's disease (HD), using imprint cytological preparations over a 18-yr period. Imprint materials from 34 HD cases were reviewed using cytomorphological and immunocytochemical studies. Twenty-six cases (76.5%) were diagnosed to be HD and 6 cases (17.6%) were suspected to be HD, but 2 cases (5.9%) were cytologically diagnosed as reactive lesions, because of an insufficient number of Reed-Sternberg (RS) cells. The 6 suspected cases were definitively diagnosed as HD, using immunocytochemistry. Immunophenotyping of RS cells in 32 cases (excluding the two cases of reactive lesions) showed CD30+ in 31 (96.9%) cases, CD15+ in 22 (68.8%) cases and CD20+ in 12 (37.5%) cases. RS cells were immunophenotypically classified into five groups: A, (CD 30+, 15+, 20-) 15 (46.9%); B, (CD30+, 15-, 20-) 5 (15.6%); C, (CD 30+, 15+, 20+) 6 (18.8%); D, (CD30+, 15-, 20+) 5 (15.6%); and E, (CD30-, 15+, 20+) 1 (3.1%). Cytomorphologic differences in RS cells were identified between group D and other groups (CD15+ and/ or CD20-). The former had a low polymorphic shape (like popcorn), and the latter had a more classical polymorphic shape. Epstein-Barr virus (EBV)-latent membrane protein-1(LMP-1) was identified in 16 (50%) cases. LMP-1 expression was found not only in classic RS cells, but also in smaller variants. These variants did not match the morphologic criteria of RS cells, but expressed the common phenotype (CD30+, CD15+/-) of RS cells, suggesting the same cellular origin as RS cells. This study demonstrated that imprint cytology from lymph node biopsies can be a useful tool for the diagnosis and the evaluation of the cellular biology of HD.