CYTOGENETIC FINDINGS AND RESULTS OF COMBINED IMMUNOPHENOTYPING AND KARYOTYPING IN HODGKINS-DISEASE

Cytogenetic studies were performed in 21 cases of Hodgkin's disease. F ourteen cases revealed chromosomally aberrant clones which could be fu lly described in 12 cases. Two cases showed different unrelated clones and five cases only single cell aberrations. Recurrent breakpoints we re 1p13/21 (six cases), 7q32/34 (five cases), 2p16/21 and 19p13 (four cases each), 4q25/28, 6q15/21 and 12q22/23 (three cases each). In two cases, a translocation between band 19p13 and band 14q11 or 14q32 was found. This finding may indicate that an unknown oncogene in 19p13 is activated by juxtaposition next to a T-cell receptor or immunoglobulin gene in 14q11 or 14q32, respectively. In eight cases each, total or p artial monosomy 4 or 6 was present suggesting that tumor suppressor ge nes in 4q or 6q play a role in tumor development in Hodgkin's disease. Moreover, the aberrant clones lacked the Y-chromosome in men and the second X-chromosome in women in eight out of nine and in two out of th ree cases, respectively. Although different cell populations, especial ly T cells, showed mitotic activity in unstimulated short term culture , combined immunophenotyping and karyotyping unequivocally demonstrate d that CD30 and CD15 positive Hodgkin and Sternberg-Reed cells represe nted the chromosomally aberrant clones.