
Among Egyptian patients, early identification additional chromosomal abnormalities (ACAs) in Ph+ metaphases in chronic phase chronic myeloid leukemia (CP-CML) is clinically important and predicts response to tyrosine kinase inhibitor (TKI) therapy as well as disease progression, according to a study published in the SOHO 2019 Meeting Proceedings Supplement in Clinical Lymphoma, Myeloma and Leukemia.
ACAs are linked to disease progression and accelerated/blast phase in patients with CML. Therefore, researchers sought to evaluate the frequency of ACAs in CP-CML at the time of diagnosis to gage their impact on patients’ response and overall survival (OS). They assessed 73 patients (31 males, 42 females, median age, 37) with CML diagnosed by chromosomal banding analysis (CBA) at the time of diagnosis including 52 CP patients and 21 accelerated/blastic crisis (AP) patients during TKI therapy. Subsequently, an analysis of ACAs in Ph’ positive metaphases was performed from January 2015 to January 2017.
Following data analysis, researchers identified 32 patients (43.8%) with ACAs and observed that ACA detection was significantly correlated with with advanced phases of CML in AP patients (13/21, 62%) compared to CP patients (19/52, 36%) (p=0.048) and notably linked with lower median OS (38 vs. 120 months) and EFS (58.3 vs. 77 months) (p=0.026 and p=0.065, respectively). The study showed that major route abnormalities were detected in 23 (31%) patients and that incidence of ACAs development was significantly higher in younger patients (<40 years) (p=0.034). Moreover, in CP–CML patients, early molecular responders at 3 and 6 months developed ACAs significantly less than non-optimal responders (6/30 (20%) vs. 13/22 (60%), p=0.049).
“Egyptian CP-CML patients develop ACAs at a higher frequency and younger age compared to western population,” the study authors wrote in their conclusion. “ACAs are a major mechanism of resistance to TKI therapy and are significantly associated with inferior OS and EFS.”