Clonal chromosomal abnormalities appearing in Philadelphia chromosome–negative metaphases during CML treatment

Abstract

Clonal chromosomal abnormalities in Philadelphia chromosome-negative (CCA/Ph-) metaphases emerge as patients with chronic phase chronic myeloid leukemia (CP-CML) are treated with tyrosine kinase inhibitors (TKIs). We assessed the characteristics and prognostic impact of 598 patients with CP-CML treated on clinical trials with various TKIs. CCA/Ph- occurred in 58 patients (10%); the most common were 2Y in 25 (43%) and trisomy 8 in 7 patients (12%). Response to TKI therapy was similar for patients with CCA/Ph- and those without additional chromosomal abnormalities (ACAs). We further categorized CCA/Ph- into those in which –Y was the only clonal abnormality, and all others. We found that patients with non –Y CCA/Ph- had worse failure-free survival (FFS), event-free survival (EFS), transformation-free survival (TFS), and overall survival (OS) compared with those without ACAs with the following 5-year rates: FFS (52% vs 70%, P 5 .02), EFS (68% vs 86%, P 5 .02), TFS (76% vs 94%, P <10% at 3 months was included in the analysis. In conclusion, non –Y CCA/Ph- are associated with decreased survival when emerging in patients with chronic-phase CML across various TKIs. This trial was registered at www.clinicaltrials.gov as #NCT00048672, #NCT00038649, and #NCT00050531 (imatinib); #NCT00254423 (dasatinib); #NCT00129740 (nilotinib); and NCT01570868 (ponatinib).