It is one of severalblood cancersthat causes the overproduction of white blood cells known asmonocytes.
There are different types of CMML, some of which are more aggressive than others.
Even so,chemotherapyand other treatments may help extend disease-free survival.

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What Is CMML?
Chronic myelomonocytic leukemia is a form ofleukemia(cancer of blood-forming cells in thebone marrow).
Even so, it is associated with a shorter life expectancy.
Symptoms
The telltale sign of CMML is an enlarged spleen, also known assplenomegaly.
This shows up when your blood contains more than 20% blast cells.
The progression to AML is associated with shorter survival times.
Although similar to CMML, CML is treated very differently.
CMML is distinctive as it does not involve the Philadelphia chromosome and its underlying cause is largely unknown.
Scientists believe that CMML may be the result of gene mutations paired with one or more triggering events.
More research is needed.
Because the transplant carries a high risk of life-threatening side effects, most people aren’t eligible.
These injectable drugs can reduce symptoms and increase survival times in people with CMML.
You may need a few cycles before you begin to respond.
Your healthcare provider may prescribe the chemo drughydroxyureato help reduce the number of monocytes.
Prognosis
CMML is associated with reduced survival times.
Hypomethylating agents can extend survival times to around 29 months, although not everyone responds to treatment.
Some people survive much longer than this.
CMML can be resistant to chemotherapy.
Between 20% and 50% of people who undergo a stem cell transplant will achieve a durable cure.
Summary
CMML is a rare form of leukemia characterized by high levels of monocytes in the blood.
The main symptoms are abdominal pain and feeling full too soon while eating.
It is not clear what causes CMML but it can occur after treatments for other cancers.
The only cure for CMML is a stem cell transplant.
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