EARLY MOLECULAR RESPONSE WITH IMATINIB THERAPY IN CHRONIC MYELOID LEUKEMIA AND ITS ASSOCIATION WITH BASELINE WHITE BLOOD CELL COUNT AND SPLEEN SIZE

Early Molecular Response With Imatinib Therapy

Abstract

Objectives: To determine the frequency of early molecular response in patients of chronic myeloid leukemia
treated with Imatinib and its association with baseline white blood cell (WBC) count and spleen size.
Study Design: Cross sectional study.
Place and Duration of Study: Combined Military Hospital, Rawalpindi Pakistan, from May to Nov 2017.
Material and Methods: Seventy eight patients of Chronic Myeloid Leukemia (CML) in chronic phase (CP) were
included in the study. Inclusion criteria were: 18 years or older, diagnosed with CML in CP with positive BCR
ABL1. Patients who were in accelerated/blast phase, or already taking any Tyrosine Kinase Inhibitors or
chemotherapy were excluded from the study. Base line WBC count, spleen size and BCR-ABL1 IS values were
recorded. All the enrolled patients were placed on Imatinib therapy (400 mg/day) and RT-PCR for BCR ABL1
transcript was repeated after three months.
Results: In our study, 60.15% of patients achieved EMR at 3 months after Imatanib therapy (p-value <0.001). In
univariate analysis, there was significant association of spleen size, baseline WBC count and percentages of
blasts in bone marrow with BCR ABL1 (IS) at 3 months (p-value <0.001), while on multivariate regression model,
significant association was found only in spleen size (p-value <0.001) with EMR.
Conclusion: A significant number of patients achieved EMR with Imatinib therapy. Spleen size at diagnosis was
the only significant factor associated with achieving EMR. It is imperative to identify patients at an early stage
who are unlikely to achieve EMR and therefore have poor over-all survival.