The purpose of this study is to better understand the use of tyrosine kinase inhibitors (TKI) in patients newly diagnosed with CML and their quality of life in a real-world setting.

Time Perspective : Most patients are expected to be a mix of retrospective and prospective data collection. Patients can be enrolled after their study index date (retrospective component) and have to be followed until 5 years from study index date are complete (time between enrollment and 5 year follow-up is the prospective component)

Inclusion Criteria:

• Newly-diagnosed chronic phase chronic myeloid leukemia (CP-CML) patients who started their first-line Tyrosine Kinase Inhibitor (TKI) treatment on imatinib, dasatinib or nilotinib in accordance with the timelines below

• 18 years or older at time of of CP-CML diagnosis

  a) Imatinib Cohorts

• Patients who started their first-line Imatinib treatment between January 2, 2008 and September 30, 2010.Patients fitting this criterion are defined as retrospective Imatinib patients

• Patients who started their first-line Imatinib treatment on or after October 1, 2010

  b) Dasatinib Cohort

• Patients who started their first-line Dasatinib treatment after the drug was approved in this indication

  c) Nilotinib Cohort

• Patients who started their first-line Nilotinib treatment after the drug was approved in this indication

• Patients are also eligible when they have already switched to a subsequent therapy (TKI or other) at the time of enrollment, as long as their first-line and subsequent CML treatment information is available at site for data entry into the study Electronic Case Report Form (eCRF)

• Receiving treatment at medical practice (eg. community-based, office-based, hospital-based, academic setting, oncology center)

Exclusion Criteria:

• Patients who are participating in an interventional trial which may influence the management of their CML disease will be excluded

Discontinuation Criteria:

• Enrolled patients who join an interventional trial which may influence the management of their CML disease will be excluded at the time of entry into the interventional trial

Patients will be recruited at oncology practices or oncology centers linked to a hospital in the North Americas, Europe and potentially at additional sites in South America, and Asia