It is often discovered incidentally on a routine blood test, then the diagnosis is confirmed by further blood tests and a bone marrow biopsy.
There is no great urgency in treatment until blood test results reach certain levels, then cytotoxic or immunosuppressive drugs are given.
Medication does not cure the disease, but slows its progress and makes the patient feel better.
Another form of treatment is bone marrow transplantation but finding a compatible donor is difficult.
Once blood tests deteriorate to the point where treatment is necessary, on drug therapy alone the average survival time is four years. If a donor can be found and marrow can be transplanted, 60% of patients can be cured.