The prognostic relevance of BCR-ABL1 transcript type, Sokal score and smoke as synergestic factor with complete cytogenetic response in CML patients treated with different TKI modalities

In chronic myeloid leukemia (CML), the influence of BCR-ABL1 transcript type, Sokal risk score and smoke on disease phynotype and cytogenetic response to treatment is still unknown and arguable. The objective of this study was to determine the prognostic significance of transcript types, risk score and smoking status among patients with CML treated with different tyrosine kinase inhibitor modalities.

Sixty CML patients were analyzed by Multiplex RT- PCR for molecular typing and banding standard protocols to follow the cytogenetic response of medications at intervals of 3 and 6 months.

The most common transcript type was e14a2 (n=35, 58.3%). There was a significant difference in cumulative incidence (CI) of complete cytogenetic response (CCR) between e14a2 and e13a2 groups (P=0.04). The time to achieve CCR was shorter in e14a2 transcript (P=0.01). The risk of resistance to drug was 4 fold higher in e13a2 group compared to e14a2. No difference was observed in CI of CCR between risk score groups (P>0.05). In smoker patients with e13a2 transcript, response to drug was lower (18 fold) than to non- smokers.

The patients with e14a2 transcript may be associated with better and faster response to imatinib. Sokal risk score is not an efficient predictive tool for response based on transcript type. The smoke in patients expressing e13a2 may be induce resistance.