Extension Study of IDEAL (Imatinib) for Chronic Myelgenous Leukemia (CML)

After the end of follow-up period of IDEAL study, subjects who agree with this extension study (IDEAL-E) will be enrolled and be followed up for additional 4 years to evaluate the duration of treatment response, disease progression, and survival status. Subjects who will be enrolled in this prospective observational study will be treated with drugs - imatinib 300-600mg / nilotinib 600mg / dasatinib 100mg / radotinib 800mg - which has been chosen by the each investigator according to the drug compliance and overall response. The drug choice will be at the discretion of each investigator, and the overall adverse event / molecular response will be monitored every 6 months in this prospective observational study.