Optimizing Early Prediction Of Outcome In CML Using The Exact Decline Of BCR-ABL Transcript Levels Within 3 Months Of Imatinib Treatment As a Prognostic Marker

Autor: Martin C. Müller, Michael Lauseker, Gabriela M. Baerlocher, Jolanta Dengler, Christiane Falge, Andreas Neubauer, Michael Pfreundschuh, Andreas Hochhaus, Alice Fabarius, Mathias Hänel, Rüdiger Hehlmann, Ulrike Proetel, Susanne Schnittger, Philipp Erben, Joerg Hasford, Christian Dietz, Cornelius F. Waller, Hermann Einsele, J. Schubert, Lothar Kanz, Markus Pfirrmann, Benjamin Hanfstein, Karsten Spiekermann, Stefan W. Krause, Susanne Saussele, Michael Kneba, Valeria Shlyakhto, Wolf-Karsten Hofmann, Frank Stegelmann
Rok vydání: 2013
Předmět:
Zdroj: Blood. 122:253-253
ISSN: 1528-0020
0006-4971
DOI: 10.1182/blood.v122.21.253.253
Popis: Introduction Early assessment of BCR-ABL transcript levels at 3 months allows the prediction of survival and may serve as a trigger for treatment intensification in CML patients with slow response to imatinib. The exact decline of BCR-ABL transcript levels within the first 3 months of treatment is defined by the ratio BCR-ABL transcripts at 3 months to BCR-ABL transcripts at baseline. This ratio might better reflect the individual biology of disease and its susceptibility to tyrosine kinase inhibition. Methods A total of 408 chronic phase CML patients (pts) with baseline and 3 month blood samples available in one single laboratory were investigated. Pts with pre-treatment before first blood sampling were excluded (imatinib with or without hydroxyurea, n=58; hydroxyurea only, n=49). A total of 301 evaluable pts (median age 52 years, range 18-85, 41% female) were treated with an imatinib-based therapy within the CML-Study IV. Median follow-up was 4.8 years. Transcript levels of BCR-ABL, total ABL, and beta-glucuronidase (GUS) were determined by quantitative RT-PCR. Exploratory landmark analyses were performed with regard to overall and progression-free survival (OS, PFS) to evaluate the prognostic significance of (i) BCR-ABL/GUS before treatment, (ii) the individual reduction of transcripts given by (BCR-ABL/GUS at 3 months) / (BCR-ABL/GUS before treatment), and (iii) the 3-month 10% BCR-ABLIS landmark. Results The median BCR-ABL/GUS ratio was 15.5% at diagnosis (0.06-107) and 0.63% at 3 months (0-84) reflecting a decline to the 0.04-fold (1.4 log reduction). i) No prognostic cut-off could be identified for BCR-ABL/GUS before treatment. ii) A reduction to the 0.35-fold of the initial BCR-ABL transcript level at diagnosis (0.46 log reduction) was identified as best cut-off according to a hazard ratio of 5.6 (95%-CI 2.3-13.4, p iii) As a comparison we investigated the 10% BCR-ABLIS landmark at 3 months with a hazard ratio of 2.4 (95%-CI 1.0-5.8, p=0.06 for PFS). With this landmark a high-risk group of 67 pts (22% of pts, 5-year PFS and OS: 87% and 90%) was separated from a good-risk group of 234 pts (78% of pts, 5-year PFS and OS: 95% and 97%). Conclusion A two-group risk stratification according to the individual reduction of BCR-ABL transcripts to the 0.35-fold of pre-treatment levels yields a superior separation of risk groups with a 5-year difference of 19% for PFS and 15% for OS. This predictive marker might identify patients at risk more precisely than 3-month 10% BCR-ABLIS. Disclosures: Hehlmann: BMS: Consultancy, Research Funding; Novartis: Research Funding. Saussele:Novartis: Honoraria, Research Funding, Travel Other; BMS: Honoraria, Research Funding, Travel, Travel Other; Pfizer: Honoraria. Hochhaus:Novartis: Consultancy, Honoraria, Research Funding, Travel Other; BMS: Consultancy, Honoraria, Research Funding; ARIAD: Consultancy, Honoraria; Pfizer: Consultancy. Müller:Novartis: Consultancy, Honoraria, Research Funding; BMS: Consultancy, Honoraria, Research Funding; Ariad: Consultancy, Honoraria, Research Funding.
Databáze: OpenAIRE