DETECTION OF NUMERICAL KARYOTYPE CHANGES IN THE GIANT-CELLS OF HODGKINS LYMPHOMAS BY A COMBINATION OF FISH AND IMMUNOHISTOCHEMISTRY APPLIEDTO PARAFFIN SECTIONS

Conventional karyotyping of Hodgkin's disease (HD) has until now yield ed only limited insight into karyotypic characteristics of this diseas e. For this reason, fluorescence in situ hybridization (FISH) using al pha-satellite chromosome-specific probes was applied to paraffin secti ons of HD tumors in order to verify numerical aberrations suggested to be specific for HD in the literature. The FISH technique was combined with immunohistochemical detection of the CD30 antigen to allow easie r identification of the Reed-Sternberg and Hodgkin (RS&H) cells. The n umber of specific FISH signals per nucleus was determined both in CD30 -positive RS&H cells as well as in non-malignant ''bystander'' cells i n order to assess differences in the signal distribution. Contrasted w ith normal lymphoid cells, the tumor cells in HD were found to be poly somic for at least one of the chromosomes analyzed (1,2,4, and 8). The technique de scribed is a reliable method for confirmation of results obtained from conventional cytogenetics, which is especially suited f or archival material or samples not containing dividing cells.