Random aneuploidy in neoplastic and pre-neoplastic diseases, multiple myeloma, and monoclonal gammopathy.

In this study we evaluated the aneuploidy rate of cells from patients considered to have a premalignant condition (monoclonal gammopathy or MGUS) and patients with multiple myeloma, as well as healthy controls. By applying a fluorescence situ hybridization technique, we estimated the random aneuploidy rate of alpha-satellite (centromeres) probes from chromosomes 9 and 18. The monosomy and total aneuploidy rates were higher in the two study groups compared to the control group. The monosomy rate was significantly higher in the MGUS group compared to the group with chromosome 18 alpha-satellite probes, a finding that was reported before in preneoplastic conditions. Our results support the cancer aneuploidy theory that carcinogenesis is initiated by a random aneuploidy, which is induced either spontaneously or by a carcinogen. The resulting karyotype instability sets a chain reaction of aneuploidization, which generates even more abnormal and eventually cancer-specific combinations and rearrangements of chromosomes.