CYTOGENETICS OF HODGKINS-DISEASE

Cytogenetic studies over the past 35 years have made a major contribut ion towards the understanding of the nature of Hodgkin's disease by de monstrating unequivocally the consistent presence of a clonal populati on of cells that have the cardinal features of malignancy e.g. more or less gross aneuploidy, frequently with complex chromosomal changes an d showing considerable variation from case to case, thus comparable to the findings in carcinomas and other solid cancers. The mode is frequ ently in the triploid-tetraploid region, as we found in 17 of 27 cases studied in this laboratory by Feulgen microspectrophotometry, compare d to only 10 cases with neardiploid modes. It is disappointing that no specific change, such as a, translocation that could give a clue to t he chromosomal location of a gene or genes involved in the etiology of Hodgkin's disease, has yet been found. Nevertheless it is clear that a number of nonrandom changes, including several that are also common in other malignancies including the non-Hodgkin's lymphomas, are frequ ently present, e.g., deletions of 1p, 6q, and 7q. Interestingly, delet ions of 4q, with loss of 4q25 --> q27, that have also been reported ma y show some specificity for Hodgkin's disease.