context: Chronic myelogenous leukemia ( CML) is a cancer that affects your blood cells and bone marrow -- the soft part inside your bones where blood cells are made. You may also hear your doctor call it chronic myeloid leukemia. It's the same disease, just a different name. With treatment, you may go into what's called "remission." For most people, that doesn't mean the cancer is completely gone, but it's less active than before. You can be in remission for many years. CML usually happens when you're middle-aged or older. The symptoms tend to come on gradually. Many of them can also be signs of other illnesses. For instance, you might feel tired, lose weight when you're not trying to, or sometimes get a fever. The disease starts with a problem in the genes of your blood cells. Sections of two different chromosomes switch places and make a new abnormal one. This new chromosome leads your body to make white blood cells that don't work as they should. They're called leukemia cells, and when they show up in your bloodstream, there's less room for healthy blood cells. Most people will never know what caused them to get CML. You don't typically get it from your parents or from infections. Your smoking habits and diet don't seem to raise your chance of getting it either. The only known risk is if you've been in contact with high levels of radiation. CML has three phases: chronic, accelerated, and blastic. Your symptoms depend on which one you're in. Chronic phase. It's the earliest stage and the easiest to treat. You might not even have symptoms. Accelerated phase. During this period, the number of blood cells that don't work right increases. You're more likely to get some of these symptoms: Feel very tired Have a fever Get bruises Have night sweats Be short of breath Lose some weight Feel less hungry Get swelling or pain on your left side (which could be a sign of an enlarged spleen) Feel pain in your bones Other symptoms may include stroke, changes in your vision, ringing in your ears, you feel like you're in a daze, and you get prolonged erections. Blastic phase. The leukemia cells multiply and crowd out healthy blood cells and platelets. In this stage, you'll have more severe symptoms, including: Infections Bleeding Skin changes including bumps, tumors Swollen glands Bone pain If you have symptoms, your doctor will want to know: What problems have you noticed? How long have your symptoms been happening? Do your symptoms come and go or are they constant? What makes you feel better or worse? Are you taking any medication? Your doctor may do more tests to confirm the diagnosis, such as: Complete blood count. It's a blood test that checks to see how many white blood cells, red blood cells, and platelets you have. Bone marrow test. It helps you figure out how advanced your cancer is. Your doctor uses a needle to take a sample, usually from your hip bone. FISH test (fluorescence in situ hybridization). It's a detailed lab test of your genes. Ultrasound or CT scans. They can check the size of your spleen. Ultrasounds use sound waves to make images that doctors and other medical professionals can read. A CT is an X-ray that takes a series of pictures inside your body. Polymerase chain reaction test. It's a lab test that looks for the BCR- ABL gene, which is involved in the process that tells your body to make too many of the wrong kind of white blood cells. Have you treated someone with CML before? What tests should I take to confirm a diagnosis? What phase of CML am I in? What treatment do you recommend for me? How will the therapy make me feel? What if the treatment doesn't work? How do I find a support group? The goal of your treatment is to destroy the leukemia blood cells in your body and restore healthy ones to a normal level. It's usually not possible to get rid of all the bad cells. If you get treatment during the early, chronic phase of CML, it can help prevent the disease from moving to a more serious level. Doctors usually give drugs known as tyrosine kinase inhibitors ( TKIs) first. They slow down the rate at which your body makes leukemia cells. Some TKIs that are commonly used include: Bosutinib ( Bosulif) Dasatinib ( Sprycel) Imatinib ( Gleevec) Nilotinib ( Tasigna) You may get bosutinib ( Bosulif) and ponatinib ( Iclusig) if other drugs don't help or make you too sick. If your disease continues to get worse after you've used two or more TKIs, your doctor may suggest a drug called omacetaxine mepesuccinate ( Synribo). Other CML treatment options include chemotherapy and biologic therapy, which uses a medication called interferon to help stir up action in your immune system -- your body's defense against germs. A stem cell transplant might cure some patients. It's a complicated procedure that's usually done only when your other treatments aren't working. Stem cells are in the news a lot, but usually when you hear about them they're referring to "embryo" stem cells that are used in cloning. The stem cells in a stem cell transplant are different. These are cells that live in your bone marrow and help make new blood cells. When you get a stem cell transplant, a donor will supply the new stem cells. You'll need to get on a waiting list to find a donor who is the right match you so that your body doesn't "reject" them. Close relatives, such as your brother or sister, are the best chances for a good match. If that doesn't work out, you need to get on a list of potential donors from strangers. Sometimes the best odds for the right stem cells for you will be from someone who is in the same racial or ethnic group as you. Make sure you tell your doctor about any medicines you take. Some don't mix well with the treatments for CML. Follow your doctor's treatment plan, eat healthy, and exercise when you feel up to it. CML is often a slow-growing form of cancer. Although it's hard to get rid of completely, many people live long lives with it. Once you're diagnosed, you should see a hematologist-oncologist, a doctor with special training in blood diseases, especially cancer. He'll come up with a treatment plan for you. Always feel free to get a second opinion from another doctor if you feel you want one. Make sure you reach out to your family and friends for the emotional backing you need. They can be a huge help as you manage your disease. It also helps to talk to others who have CML. Ask your doctor about how to join a support group, where you can meet people who are going through the same things you are. The Leukemia & Lymphoma Society can help you find services and support. It has up-to-date information about treating and living with CML, including help for caregivers.