[Chronic myelogenous leukemia: monitoring and predictors of a favorable response to treatment with imatinib].

The expected five-year survival of chronic-phase chronic myeloid leukemia patients treated with tyrosine kinase inhibitors is over 90%. Little data is available regarding the results in the Argentinian population. This information might be of interest as generic imatinib is now available in the region. The aim of this study is to provide information on monitoring and the long-term treatment with imatinib outside of a controlled clinical trial, as well as to analyze the predictive effect of early responses to achieve molecular remission 4.0 (RM 4.0) and the detection of variables that may condition treatment failure. We included 106 patients, who received imatinib 400 mg daily as first-line inhibitor for a median of 8.9 years (IQR 5.8-11.7) between June 2000 and December, 2015. Overall survival was 93%. At latest follow-up 74% of patients continues on initial imatinib. The achievement of response at targeted milestones (6, 12 months) was associated with increased failure-free survival: 87% vs. 56%, p = 0.007; 90% vs. 69% p = 0.01 and was independently associated to RM 4.0: OR 5.6 (95% CI: 1.6-19.0); OR 5.3 (95% CI: 1.4-21.0) p = 0.006. After long-term follow-up, imatinib provided high-rates of response and survival. The prognostic value of response at targeted milestones was confirmed. This study reinforces the importance of molecular monitoring under IS standardization at known timepoints and this must continue to be a target in Argentina.