Efficacy and Safety of Dacogen

• Adverse event [ Time Frame: every cycle ] [ Designated as safety issue: Yes ]
• Cytogenetic response [ Time Frame: After 4 cycle ] [ Designated as safety issue: No ]
• Survival [ Time Frame: End of treatment ] [ Designated as safety issue: No ]

• Adverse event [ Time Frame: at the end of every 4 week cycle ] [ Designated as safety issue: Yes ]
• Cytogenetic response [ Time Frame: at the end of every 4 week cycle ] [ Designated as safety issue: No ]
• Survival [ Time Frame: at the end of every 4 week cycle ] [ Designated as safety issue: No ]

The objective of this study is to evaluate the efficacy and safety data of the patients treated with decitabine (Dacogen) intravenous injection

The current trial is a prospective, multi-center, Phase 4, observational study that will collect domestic data on the efficacy and safety of a five-day decitabine (Dacogen) regimen in domestic patients with Myelodysplastic Syndrome (MDS). The results will be utilized as basic data to establish the domestic guidelines for decitabine treatment. This study is designed to observe the response rate and safety of decitabine in patients with MDS who were treated with decitabine. All adverse events reported from the time a signed and dated informed consent form is obtained until the last visit will be evaluated. Observational Study - No investigational drug administered. The patient will receive decitabine intravenous injection 20mg/m2 once a day for 5 consecutive days for every 4 weeks.

The patients who signed the subject informed consent form among the patients with myelodysplastic syndrome who were treated with decitabine

Inclusion Criteria:

• The patients diagnosed with (primary or secondary) Myelodysplastic Syndrome including chronic myelomonocytic leukemia (CMML)
• Patients with an International Prognostic Scoring System >= Int-1
• Patients who have never treated with hypomethylating agent(azacitidine and decitabine)
• Female patients who are postmenopausal or received contraceptive operation or refrain from sexual relations. Women of childbearing potential should conduct an effective method of birth control (oral contraceptives, injections, intrauterine device, double barrier method, contraceptive patch and male partner's sterilization),in case of male patients who will not have a baby within 2 months after the completion of decitabine therapy
• Patients who signed an informed consent document indicating that they understand the purpose of and procedures required for the study and are willing to participate in the study

Exclusion Criteria:

• Patients diagnosed with acute myelogenous leukemia (AML, bone marrow stem cell counts exceeding 20 %) or other progressive malignant diseases
• Patients with active infection of virus or bacteria
• Patients who used to be treated with azacitidine or decitabine
• Patients who are hypersensitive to excipients of decitabine
• Patients who are pregnant of breast-feeding