Chronic myeloid leukemia (CML) is often called the “good cancer.” That’s because over the last 20 years, patients and doctors have seen CML become more manageable for many people.
But the CML journey doesn’t turn out to be quite as “good” for some people. Along the way, some patients do not respond to their medication or they experience intolerable side effects.
How CML affects you
If you’ve had CML for some time, you may be familiar with the disease. If that’s the case, skip ahead and take this quiz. It’s designed to help you learn how CML may be affecting your life.
If you’d like to learn more about CML, review the information below.
What causes CML?
CML occurs when:
- The blood-forming cells of the bone marrow create too many white blood cells
- These damaged white blood cells crowd out healthy red blood cells, white blood cells, and platelets
- This can lead to health problems
- More than 95% of people with CML have Philadelphia chromosome–positive chronic myeloid leukemia
- Ph+ CML is caused by an abnormal fusion gene, called BCR-ABL1, which results from a change in chromosomes in the body
- Each cell in the human body has 23 pairs of chromosomes
- In CML, pieces of chromosomes 9 and 22 break off and trade places
- This change can create a new abnormal chromosome—the Philadelphia (Ph+) chromosome
- It creates the defective BCR-ABL1 gene, which produces an abnormal protein called BCR-ABL
The importance of staying in the chronic phase of CML
Instead of being categorized in stages like many cancers, CML is classified into 3 phases:
- Chronic phase
- Accelerated phase
- Blast phase
Your doctor may discuss with you the importance of keeping CML from progressing from the first phase—the chronic phase—to the more advanced accelerated or blast phases. If CML is left untreated, it is more likely to progress.
Estimated 5-year cancer survival rates from diagnosis
Based on data available from 2010 to 2016, the estimated 5-year cancer survival rate for those with CML is 70%. That’s improved from a 5-year survival rate for CML of 36% among patients diagnosed between 1990 and 2000, and improved from 56% among those diagnosed between 2001 and 2009.
While there has been significant progress in CML over the years, there are still patients who don’t do as well as others.
Setting treatment goals
It’s important to work closely with your doctor and keep up with your appointments. While every patient is different, your doctor may identify goals for you, such as:
- Getting blood cell counts back within a normal range
- Reducing the number of leukemic cells in your body
- Reducing the amount of BCR-ABL protein in your body down to an undetectable level
- Keeping Ph+ CML in chronic phase
Milestones in CML
Your doctor may discuss treatment milestones with you in CML. Keep in mind, treatment goals may vary from patient to patient.
Complete Hematologic Response (CHR)
- Blood counts for red blood cells, white blood cells, and platelets return to normal
- There are no immature blood cells
- There are no signs and symptoms of disease
Complete Cytogenetic Response (CCyR)
- If there are no Ph+ cells detected in the bone marrow, your doctor may say that you have a CCyR
- With CCyR, the amount of BCR-ABL1 is ≤1% of all the cells in your blood
- This means that 1 out of every 100 cells has the BCR-ABL1 gene compared to baseline
Major Molecular Response (MMR)
- With MMR, the amount of BCR-ABL1 in the blood is ≤0.1%
- This means that 1 out of every 1000 cells has the BCR-ABL1 gene compared to baseline
Know your numbers
Your doctor may want you to go for regular blood tests to see if you are responding to your medication. Here are tests your doctor may order:
Complete Blood Count (CBC)
- Measures the amount of red blood cells, white blood cells, and platelets in the blood
Standard Cytogenetic Test
- Analyzes a small sample of bone marrow under a microscope to determine the number of cells with the Ph chromosome
Fluorescence In Situ Hybridization (FISH) Test
- A standard cytogenetic test may not detect all the CML cells in the blood. Your doctor may order a FISH test, which uses fluorescent dyes and a fluorescent microscope to measure the number of cells with the Ph chromosome
Quantitative Polymerase Chain Reaction (qPCR or molecular) Test
- qPCR testing is sensitive enough to detect the smallest amount of leukemic cells in the blood and bone marrow
- It can identify 1 cancer cell among anywhere from 100,000 to 1 million cells
- When you go for qPCR testing, be sure the lab uses a standardized scale called the International Scale to measure your BCR-ABL1 level. It’s a reliable way to measure progress toward your goals
Gene Mutation Testing
- Looks for mutations in the BCR-ABL1 gene that may cause certain medications to stop working
- Your doctor may call this a BCR-ABL1 kinase domain mutation analysis
An increase in your BCR-ABL1 levels can be a red flag for your doctor. That’s why it’s important to go for any blood tests your doctor prescribes and discuss what your results mean with your doctor.