Clonal evolution including 14q32/IGH translocations in chronic lymphocytic leukemia: analysis of clinicobiologic correlations in 105 patients

AbstractTo better define the significance of clonal evolution (CE) including 14q32 translocations involving the immunoglobulin heavy chain gene (IGH) in chronic lymphocytic leukemia (CLL), 105 patients were analyzed sequentially by fluorescence in situ hybridization (FISH) with the following panel of probes: 13q14/D13S25, 11q22/ATM, 17p13/TP53, #12-centromere and 14q32/IGH break-apart probe. CE was observed in 15/105 patients after 24–170 months (median 64). Recurring aberrations at CE were 14q32/IGH translocation in seven patients; other aberrations were 17p −, 11q −, biallelic 13q − and 14q32 deletion. CE was detected in 15/58 pre-treated patients; in contrast, none of 47 untreated patients developed CE (p < 0.0001). In two cases the appearance of 14q32/IGH translocation was first detected in the bone marrow (BM) or in the lymph node (LN) and 13–58 months later in the peripheral blood (PB). ZAP70 + and high-risk cytogenetics predicted for the occurrence of CE with borderline statistical significance (p ...