Milestones and Monitoring in Patients with CML Treated with Imatinib

Imatinib is the therapeutic standard for newly diagnosed patients with chronic myeloid leukemia (CML). Recent updates of the IRIS trial, a study of standard-dose imatinib in newly diagnosed chronic-phase patients treated with 400 mg imatinib daily, suggest a stabilization of progression-free survival curves at a high level, implying that the majority of patients will do well on standard therapy. However, some 20% to 30% of patients will fail on imatinib and require alternative therapies. Identification of those patients likely to fail would be desirable to allow for more intensive therapy up front. After a brief overview of the history of CML, this paper will review current recommendations for staging of CML patients at diagnosis. Next, the various tests used to monitor their response to imatinib will be discussed in the context of the currently accepted criteria for imatinib failure and suboptimal response. Last, approaches to identify high-risk patients at diagnosis will be addressed.