We studied chromosomal abnormalities in 67 patients with plasma cell disorders including multiple myeloma and plasma cell leukemia. Twenty patients, 17 of whom had advanced diseases, showed clonal abnormalities. Chromosomes 14, 1, 6, 7, and 11 are involved in structural abnormalities. The rearrangement of band 14q32(14q+), which was found in 10 patients, is likely to be specific for multiple myeloma. We identified a 14q+ as a t(6 ; . 14)in two patients, a t(14 ; 18)in two, a t(7 ; 14)in one, and a t(3 ; 14)in one, but not in the remaining four Southern blott analysis showed the germ-line configuration of bcl2 gene in 15 patients.
A 14q+ is rather specific for leukemic myeloma and plasma cell leukemia. Both 14q+ and rearrangements of chromosome 1 are associated with elevated LDH, suggesting high tumor-burden and advanced disease. Ten patients with a 14q+ tend to have a short survival from the time of chromosomal analysis when compared with six with other chromosomal abnormalities.
In one of two patients who developed acute nonlymphocytic leukemia, we found monosomy 7 that is specific for therapyassociated leukemia. We also described a rare case carrying both a. Ph and a 14q+ on the same metaphase.