Introduction
Chronic myeloid leukemia is a myeloproliferative disorder which is
characterized by increase amplification of the granulocytic cell line
with fairly normal differentiation. The main hallmark of CML is
deregulated tyrosine kinase activity catalyzed by BCR/ABL1 fusion
protein which results on Philadelphia chromosome(1).
Treatment of CML has been revolutionized with the presence of BCR-ABL1
targeting TKI,which has improved the overall survival and quality of
patient’s life.
Imatinib
was the first of these to be used in the treatment of CML(2)..Several
other tyrosine kinase inhibitors (TKIs) have been developed and tested
in patients with CML, most notably
dasatinib,
nilotinib,
bosutinib,
and
ponatinib.
Despite the excellent outcome, half of the patients will eventually fail
due to intolerance or resistance to first line treatment, with many of
them requiring a third or even further lines of therapy(3, 4).
We report a case of CML who initially didn’t tolerate dasatinib and
Nilotinib but showed excellent response to Bosutinib and achieved major
molecular response in just 4 months of therapy.