Assessment of molecular response after tyrosine kinase inhibitors & serum granulocyte-macrophage colony-stimulating factor levels in Egyptian patients with chronic myelogenous leukemia in chronic phase

Abstract

BackgroundIn chronic myelogenous leukemia (CML), one of the most important & documented benefits of the profitable use of tyrosine kinase inhibitors (TKIs) is achieving major molecular response (MMR) & undoubtedly raising the life expectancy. We evaluate the molecular response after one year of 32 newly diagnosed Egyptian CML patients in chronic phase receiving TKIs (imatinib vs nilotinib). Quantitative assessment of BCR-ABL1 mRNA transcripts using real-time reverse transcription polymerase chain reaction was done. Also, baseline quantitative detection of serum GM-CSF level was done using enzyme linked immunosorbent assays technique together with correlation to molecular response. ResultsThirty-two patients were included in the study, but the molecular response was assessed in only 17 patients; 6 patients were under imatinib treatment and 11 patients received nilotinib. Overall within 1 year, 7/17 (41.2%) patients achieved major molecular response (MMR) with median BCR-ABL1 level of 0.06% on the international scale (IS). Five patients (29.4%) reached MR4 with median BCR-ABL1 level 0.007% on IS. Regarding TKIs therapy, each MMR and MR4 was noticed in 2/6 (33.3%) patients who received imatinib treatment with median BCR-ABL1 level of 0.01% & 0.005% on the IS, respectively. However, MMR and MR4 were detected in 5/11 (45.4%) & 3/11 (27.3%) patients who received nilotinib treatment, respectively with median BCR-ABL1 level 0.06% & 0.008% on the IS, respectively. Median serum GM-CSF level was higher in patients who reached MR4 than patients who achieved MMR but it did not reach significant difference (p value = 0.7). ConclusionThis study demonstrates the molecular profile of Egyptian CML patients after TKIs treatment. Also, it assesses the baseline serum GM-CSF levels to predict therapeutic outcome in CML patients.