Age has a profound effect on the incidence and significance of chromosome abnormalities in myeloma

A simple high throughput micro-fluorescence in situ hybridisation technique ( FISH) was used to detect chromosome 13 deletions ( Delta 13), immunoglobulin heavy chain ( IgH) rearrangements, t( 11; 14)( q13; q32), t( 4; 14)( p16; q32), t( 14; 16)( q23; q32), p53 loss, and numerical changes of chromosomes 3, 6, 7, 9, 10, 11 and 17 in 228 cases of multiple myeloma ( MM), including 33 asymptomatic/smouldering MM ( SMM). The patients were not part of a clinical trial and were from 30 different hospitals. In all, 98.4% of cases were abnormal, with 43% having IgH rearrangements and 42% Delta 13. The low incidence of IgH rearrangements was due to a decrease in this finding with age ( P = 0.001) and the relatively high proportion of elderly patients in our study population ( 41% > 70 years old). The incidence of specific IgH translocations was t( 4; 14) 11%, t( 11; 14) 16% and t( 14; 16) 3%. Univariate statistical testing showed Delta 13 ( P = 0.002), and t( 14; 16) ( P = 0.005) to be associated with shorter survival. This effect was exaggerated for patient's aged 70 years or under but no effect on survival was seen for those over 70 years. In younger patients t( 4; 14) ( P = 0.044) and p53 deletion ( P < 0.001) were also significant poor prognostic indicators. Multivariate analysis showed Delta 13 and t( 14; 16) to be independent prognostic variables when considered with age and clinical parameters.