Impact of the Normalized Copy Number of <i>BCR-ABL</i> Transcript upon Diagnosis on Prognosis in CML Patients Treated with Imatinib-Mesylate

Quantification of the BCR-ABL transcript is recommended to follow-up CML patients treated by imatinib mesylate (IM). Results are expressed as a normalized copy number (NCN) of BCR-ABL. We studied a cohort of 98 CML patients under IM as a first treatment and monitored by RQ-PCR after 12, 18 and 24 months according to the European LeukemiaNet recommendations. Our results support the hypothesis of an independent correlation between BCR-ABL NCN at diagnosis and major molecular response at 18 and 24 months in an inverse relationship. We also highlighted the possibility to use the NCN at diagnosis as a warning at diagnosis, and may be useful to identify patients who could benefit of a more rigorous follow-up.