ABSTRACT
Splenic marginal zone lymphoma (SMZL) is a B-cell lymphoproliferative disorder with characteristic clinical, immunophenotypic, cytological and histological features. Some karyotypic abnormalities have been related to this disorder and most of them are usually complex and difficult to define. The aim of present study was to characterize new chromosomal aberrations involved in this disease. We performed conventional banding cytogenetics and Spectral Karyotyping (SKY) technique in 23 patients diagnosed with SMZL having a complex karyotype among a series of 160 SMZL cases. Del(7)(q22-q32) and trisomy 3/3q were the most common chromosomal aberrations. In addition, new translocations involving chromosomes 3, 6, 8, 9, 12 and 14q32 region were detected.
Subject(s)
Chromosome Aberrations , Lymphoma/genetics , Splenic Neoplasms/genetics , Adult , Aged , Aged, 80 and over , DNA-Binding Proteins/genetics , Female , Genes, Immunoglobulin , Humans , In Situ Hybridization, Fluorescence , Karyotyping , Male , Middle Aged , Proto-Oncogene Proteins c-bcl-6 , Translocation, GeneticABSTRACT
Myelomatous plasma cells show a high heterogeneity both in their immunophenotypic characteristics as well as in their cytogenetic features. Thus far, no extensive studies have been carried out to explore whether such antigenic diversity is associated with specific genetic characteristics. We have investigated the relationship between the immunophenotypic profile at plasma cell and both their DNA ploidy status (evaluated by flow cytometry) and specific genetic features (ascertained by fluorescence in situ hybridization) in a large series of 915 patients with newly diagnosed multiple myeloma. The non-hyperdiploid multiple myeloma group (n = 454, 52%) was associated with a significantly higher frequency of positivity for CD28 and CD20 as well as a higher incidence of CD56(-) and CD117(-) cases (P < 0.001). Remarkably, 13q deletion and immunoglobulin heavy chain (IGH) gene rearrangements, which were significantly more common in non-hyperdiploid multiple myeloma, showed a strong association with CD117(-) cases. IGH translocation to 11q13 was associated with reactivity for CD20 (P < 0.001), down-regulation of CD56 (P < 0.001), and lack of expression of CD117 (P = 0.001). By contrast, IGH translocations to other chromosome partners were almost exclusively found among CD20(-) and CD117(-) cases (P < 0.001). These results suggest that genetic categories in multiple myeloma exhibit particular immunophenotypic profiles which in turn are strongly associated with the DNA ploidy status.
