Chronic Myeloid Leukemia
April 19, 2024
This page was reviewed under our medical and editorial policy by Guido Marcucci, M.D., Chair, Department of Hematologic Malignancies Translational Science, City of Hope Duarte
Chronic myeloid leukemia (CML) is a type of blood cancer that develops when immature stem cells in the bone marrow, called myeloid cells, don’t mature normally into healthy white blood cells. Instead, the immature cells form abnormal leukemia cells. It is sometimes called chronic myelogenous leukemia, CML leukemia or simply CML.
Mature, healthy white blood cells help fight disease and infection. In patients with CML, a genetic change triggers a buildup of abnormal white cells called granulocytes in the blood and bone marrow. These leukemia cells crowd out healthy white blood cells, red blood cells and platelets, which may lead to infections, anemia and bleeding.
Chronic myeloid leukemia is a slow-growing type of blood cancer. People with CML have a gene mutation that causes myeloid stem cells to grow into unhealthy white blood cells. The cancer may also affect levels of blood-clotting platelets and decrease oxygen-carrying red blood cells.
The CML gene mutations result from DNA damage that occurs after a person is born. They aren’t inherited or passed on to children. According to the American Cancer Society, about half of people diagnosed with CML are 65 or older, and it’s rare in children.
Symptoms of chronic myeloid leukemia may include fever, weakness, night sweats and fatigue. A shortage of blood platelets from CML may cause excessive bleeding and bruising. Patients with CML also have an increased risk of infection.
Bone pain is another CML symptom. It occurs when leukemia cells move from the marrow into the joints or bone surface.
Since the spleen stores blood cells, an elevated, abnormal white blood cell count may cause it to become enlarged, leading to abdominal pain, fullness, loss of appetite and weight loss.
Symptoms aren’t always present in patients with CML, and diagnosis often begins when routine blood tests reveal abnormalities. City of Hope® patients have access to a team of expert clinicians and doctors. They rely on blood tests, bone marrow biopsies and genetic and imaging tests to inform diagnosis and discuss disease staging.
CML is grouped into one of three phases — chronic, accelerated or blast — based on the amount of blasts in the bone marrow and other factors.
Several treatment options are available for people with CML. They are selected based on the patient’s phase of cancer, overall health, possible side effects and personal preferences. The latest advances in targeted therapy, interferon therapy, chemotherapy, surgery, stem cell transplantation and radiation therapy may all be discussed and delivered with care at City of Hope.
Each patient is unique. The care team will present all of the treatment options available and discuss expected outcomes and survival estimates.
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https://www.cancer.org/cancer/types/chronic-myeloid-leukemia/about/what-is-cml.htmlAmerican Society of Clinical Oncology (2018, March). Leukemia — Chronic Myeloid — CML: Introduction.
https://www.cancer.net/cancer-types/leukemia-chronic-myeloid-cml/introductionAmerican Cancer Society (2018, June 19). What Causes Chronic Myeloid Leukemia?
https://www.cancer.org/cancer/types/chronic-myeloid-leukemia/causes-risks-prevention/what-causes.htmlAmerican Cancer Society (2024, January 17). Key Statistics for Chronic Myeloid Leukemia.
https://www.cancer.org/cancer/types/chronic-myeloid-leukemia/about/statistics.htmlAmerican Cancer Society (2024, February 27). Signs and Symptoms of Chronic Myeloid Leukemia.
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https://www.cancer.org/cancer/types/chronic-myeloid-leukemia/treating/interferon-therapy.html#
Leukemia Patient Stories





Our Chronic Myeloid Leukemia Expertise

City of Hope has been named a best hospital for cancer by U.S. News & World Report for over a decade. As a founding member of the National Comprehensive Cancer Network, our doctors also help develop and improve evidence-based leukemia treatment guidelines for patients nationwide.
Program Highlights:
- A multidisciplinary team of specialists – including hematologists, medical and radiation oncologists, scientists, supportive care experts, and other professionals – who work together to provide coordinated, personalized care for you and your loved ones.
- The Gehr Family Center for Leukemia is home to a team of basic scientists whose laboratory research focuses on furthering our understanding of the causes of leukemia (leukemogenesis) and developing new disease-specific therapeutics.
- Comprehensive molecular profiling and risk assessment tests that can help identify treatments that will produce the best outcomes.
- A world-class bone marrow and stem cell transplant program with better-than-expected survival outcomes for over 10 years.
- Leading-edge clinical trials for leukemia that are unavailable elsewhere, including CAR T cell immunotherapy, mutation-specific drugs and novel stem cell transplant regimens.
- Total marrow irradiation can target radiation therapy to bone marrow while minimizing exposure to healthy tissues and organs.
- Specialized observation programs for slow-growing leukemia subtypes allow our doctors to deliver timely therapies when they are the most effective.
- A long-term follow-up program to minimize the risk of recurrence and improve the quality of life for leukemia survivors.

City of Hope is one of the few facilities designated a comprehensive cancer center by the National Cancer Institute.

Our developments in the areas of breakthrough cancer drugs, bone marrow transplants and CAR T cell therapy are recognized internationally.

Our leadership in research and innovation continually enhances our ability to provide novel and differentiated approaches to cancer care.