Classical Monocyte Kinetics in Chronic Myelomonocytic Leukemia

Inclusion Criteria for patients with CMML:

* Adult aged 18 years or over
* CMML diagnosis according to the WHO 2016 criteria
* Untreated patient or patient who did not receive a cytoreductive drug such as Hydroxyurea or an Erythropoiesis Stimulating Agent (ESA), or a growth factor, or Eltrombopag within the last 2 months or patient who did not receive a hypomethylating drug (Azacytidine or Decitabine) within the last 3 months
* Affiliated to a social security system or beneficiary of the same
* Able and willing (in the Investigator's opinion) to comply with all study requirements
* Able to comprehend the Information Sheet and willing to give written informed consent prior to any protocol-specific procedures performed
* Willing to allow the Investigator to review data from the hospital medical records
* For women of child-bearing age only, willingness to practice continuous effective contraception during the study. Women of childbearing potential must have a negative urine β-HCG pregnancy test within 15 days prior to the first administration of deuterium-labeled glucose. Sexually active male patients must agree to use condoms during the study. Also, it is recommended their women of childbearing potential partner use an effective method of contraception during the same period

Exclusion Criteria for patients with CMML:

* Severe anemia (Hb \< 10 g/dL)
* Severe thrombocytopenia (Platelets \< 50 G/L)
* Transfusion dependency
* Active or recent infection or febrile illness (\<1 month)
* Currently active inflammatory or autoimmune condition
* Current systemic steroid therapy or other immunomodulatory drugs
* Recent vaccination (\< 1 month)
* Recent surgery (\< 1 month)
* Active malignant disease
* Renal disease (serum creatinine\> 300µmol/L)
* Hepatic disease (transaminase levels \>3x ULN)
* Severe or unstable cardiovascular disease
* Pregnancy or breastfeeding
* Other current active medical condition which the Investigator considers a risk for entry in the study
* Simultaneous participation in another concurrent research study that conflicts e.g. if it also involves blood sampling
* Patient under guardianship or deprived of his liberty by a judicial or administrative decision or incapable of giving its consent

Inclusion Criteria of age-matched healthy donors:

* Volunteers aged 55 years or over
* Able and willing to comply with all study requirements
* Able to comprehend the Information Sheet and willing to give written informed consent prior to any protocol-specific procedures performed
* For women of child-bearing age only, willingness to practice continuous effective contraception during the study. Women of childbearing potential must have a negative urine β-HCG pregnancy test within 15 days prior to the first administration of deuterium-labeled glucose. Sexually active male patients must agree to use condoms during the study. Also, it is recommended their women of childbearing potential partner use an effective method of contraception during the same period.

Exclusion Criteria of age-matched healthy donors:

* Current treatment for any type of disease
* Current active medical condition
* Recent vaccination (\< 1 month)
* Recent surgery (\< 1 month)
* Pregnancy or breastfeeding
* Simultaneous participation in another concurrent research study that conflicts e.g. if it also involves blood sampling
* Subject under guardianship or deprived of his liberty by a judicial or administrative decision or incapable of giving its consent