[Clinical observation of chromosomal abnormalities in Ph negative cells of chronic myeloid leukemia patients treated with tyrosine kinase inhibitors].

OBJECTIVE

To observe the clinical features, characteristics and outcomes of chromosomal abnormalities in Philadelphia negative cells (Ph(-)CA) of chronic myeloid leukemia (CML) patients treated with tyrosine kinase inhibitor (TKI), and provide the evidence for clinical treatment.

METHODS

We collected and analyzed the clinical and laboratory data of 8 CML patients treated in the affiliated Tumor Hospital of Zhengzhou University from September 2011 to July 2015 and Ph(-)CA occurred after TKI therapy. Karyotypes and BCR-ABL fusion genes were analyzed by R-banding and real-time quantitative polymerase chain reaction (RT-PCR), respectively.

RESULTS

6 cases were male and 2 cases were female, with a median age of 51 (31-75) years old. 6 patients had low Sokal risk scores and 2 had intermediate scores. 4 cases of Ph(-) CA occurred with imatinib, 1 case with dasatinib and 3 cases with nilotinib. The median duration of Ph(-) CA appearance was 12.0 (1.7-34.5) months since taking TKI. Chromosomal abnormality +8 was the most common type in Ph(-)CA, which accounted for 50.0%, followed by -7 (25.0%). When found Ph(-)CA, all patients had complete hematologic response (CHR), but none got main molecular response (MMR). The Ph(-)CA had gone in 7 cases at the end of follow-up and the median duration was 6.2 (2.5-31.5) months. After Ph(-) CA disappeared, 1 patient obtained MMR and 2 cases achieved complete molecular response (CMR), but Ph(+) clone recurred in 1 case.

CONCLUSION

Ph(-)CA can be found in CML patients treated with imatinib, dasatinib and nilotinib, and +8 is the most common Ph(-)CA. So detection of karyotype is significant during treatment. Although most Ph(-)CA can disappear, -7/7q- or other complex karyotypes should be monitored closely.