We report a case of primary mediastinal (thymic) large B-cell lymphoma (PMBL) with an initial karyotype containing numerical chromosomal aberrations: +X, +9, +12, +21, and a novel translocation t(2; 11)(q31; q23 similar to 24) with a duplication of the derivative chromosome 11. Subsequent multicolor fluorescence in situ hybridization (M-FISH) analysis revealed a der(14)t(8; 14)(q24;q32).
Further analysis using fluorescence in situ hybridization (FISH) with locus-specific probes revealed loss of the entire IgH locus from the der(14)t(8;14) and relocation of MYC to this derivative chromosome 14. Our data show definitively the existence of the t(8;14) in PMBL, previously only suspected.
This finding supplies additional evidence that a translocation-mediated MYC activation may be an important event in the pathogenesis of this unique lymphoma.