The aim of this study is to observe and analyze the clinical efficacy of Venetoclax+HMAs regimen in the treatment of newly diagnosed higher-risk MDS and CMML cases, and to compare the efficacy of venetoclax +HMAs regimen with that of HMAS regimen alone, in order to provide a normative scheme and basis for clinical use.

Inclusion Criteria:

1. Age ≥18 years old, male or female;
2. MDS or CMML diagnosed by the 2016 or 222 WHO criteria, with a sustained survival of at least 12 weeks;
3. received more than two cycles of Venetoclax plus HMAs or HMAs alone without prior disease specific or allogeneic hematopoietic stem cell therapy (before initiating Venetoclax or HMAs, Medications such as hydroxyurea were allowed to reduce the white-cell count to 1.0×109 per liter or less.) ;
4. bone marrow blast cell count (BM blast > 5%) or IPSS-R score > 3 (intermediate risk, high risk, very high risk);
5. Eastern Cooperative Oncology Group (ECOG) performance status ≤2;
6. complete case information could be obtained.

Exclusion Criteria:

1. patients who did not meet the inclusion criteria;
2. inability to obtain complete case information or to follow protocol steps or follow up on time;
3. other conditions considered by the investigators to be unsuitable for inclusion.

Adults aged 18 years or older with newly diagnosed myelodysplastic agenda syndrome (MDS)and chronic myelomonocytic leukemia (CMML)according to the 2016WHO or 2022 WHO criteria