Measurable Residual Disease Testing

Treating blood cancer is complex. Doctors use different tests to learn as much as possible about your cancer. This allows treatment to be tailored to fit your unique needs. One important method that doctors use to monitor blood cancer is checking for measurable residual disease (MRD). Knowing how many cancer cells remain during or after treatment can be helpful. It gives you and your doctor a new way to track and talk about how to best manage your care.

If you are hearing about MRD for the first time, you may wonder what to do next. Here is some background information and advice to help you get started.

What is MRD?

MRD refers to the small number of cancer cells that remain in your body during and after cancer treatment. It is sometimes called minimal residual disease. Traditional lab tests may miss these cancer cells. Knowing how many cancer cells remain during or after treatment can be helpful. It gives you and your doctor a new way to track and talk about how to best manage your care.

MRD testing is used in blood cancers, including:

• Acute lymphoblastic leukemia (ALL)
• Acute myeloid leukemia (AML)
• Chronic myeloid leukemia (CML)
• Lymphomas
• Multiple myeloma

Why is MRD testing important?

The goal of cancer treatment is to destroy as many cancer cells as possible. That’s because diseased cells that remain after treatment may start to multiply and cause your cancer to return or spread. Testing for MRD tells your doctor whether there are cancer cells remaining in your body. By knowing how much MRD you have, your doctor can better understand how your body is responding to treatment. This can help your doctor decide whether you might benefit from new or different treatments.

MRD testing is part of what’s known as precision medicine. It is sometimes called personalized medicine. Precision medicine gives doctors insight into the genes and proteins in your cancer cells. This information allows your doctor to create a treatment plan that best targets your specific cancer.

What does MRD testing show?

By using a sample of your bone marrow or blood, your doctor can determine how many cancer cells remain in your body. MRD testing is so sensitive that it can find 1 cancer cell in 10,000 healthy cells. It may even be able to detect 1 cancer cell in 1 million healthy white blood cells. MRD-negative means that there are no traces of detectable cancer left. MRD-positive means that some cancer cells are still present.

MRD status is important because people who are MRD-negative may live longer without disease than those who are MRD-positive. By knowing your MRD status, your doctor can:

• Determine how your cancer is responding to treatment
• Confirm and/or monitor remission
• Recognize cancer recurrence sooner
• Pinpoint if you might benefit from other treatments, such as combination therapy with a stem cell transplant.

The technique used to determine your MRD status depends on the type of blood cancer you have. The most widely used, highly sensitive techniques are:

• Flow cytometry
• Polymerase chain reaction (PCR)
• Next-generation sequencing (NGS)

Flow cytometry checks for abnormal proteins. PCR and NGS identify cancer cells based on genetic mutations. MRD results take between 1 day to several weeks depending on the technique used.

When is MRD testing recommended?

Your doctor will tailor when to use MRD testing to your unique situation. For example, your doctor may recommend MRD testing:

• After the final cycle of a planned combination therapy
• After stem cell transplant
• During treatment to confirm the depth of remission
• At the 1-year point of maintenance therapy
• At regular intervals after treatment is completed

Should I get tested for MRD?

The choice about whether to get tested for MRD and what to do with your MRD test results is a personal one. To help you decide whether to be tested for MRD, ask your cancer care team the following questions:

• Do I need to have an MRD test? Why?
• When should I have an MRD test?
• What does an MRD-positive or an MRD-negative test result mean for me?
• How will MRD results affect my treatment plan?
• What types of MRD tests are available for my specific cancer? How do they vary in sensitivity and accuracy?
• Is MRD testing covered by my insurance? Is financial assistance available?

Other questions to discuss with your health care team include the following:

Are there any side effects from MRD testing?

You may have some discomfort from having a blood or bone marrow sample drawn for the MRD test. Be sure to ask your doctor what to expect and whether pain medication is available.

Will I have to get tested for MRD more than once?

You and your doctor will decide whether more than one MRD test is necessary. For example, a positive MRD result may mean that you begin additional treatment. A follow-up MRD test might be ordered to see if the new treatment is effective. If your doctor recommends repeat testing, ask that your blood or bone marrow be sent to the same lab that handled your previous MRD tests. Using the same lab will help you and your care team make accurate comparisons about your MRD status.

How much does MRD testing cost?

Many cancer tests, including MRD tests, can be costly. Talk with your health care team up front about any financial concerns with MRD testing. Also, check with your health care plan before having an MRD test to find out what the cost will be.

Many treatment centers have resources to help patients cover the costs of testing and treatment. Ask your health care team for a financial counselor to talk through financial issues before beginning treatment. Ask if you qualify to get MRD testing or if it might be covered as part of a clinical trial.

For help on coping with cancer costs, call 888-793-9355.

Where can I find support after receiving my test results?

With each round of treatment and testing, there is uncertainty. To make the treatment and testing process smoother, take one or more of the following steps:

Ask for help. Find someone to help you keep everything straight and to help with all the things you have to manage. If you have been assigned a patient navigator (sometimes called a nurse navigator), use them as much as possible. If you haven’t been assigned one, ask your health care team how to get one. Patient navigators are people dedicated to helping guide you through the complex health care system.

Communicate with your health care team. Open communication with your health care team is critical to your treatment. Don’t be afraid to ask questions. Let your health care team know if you are having side effects or struggling with the emotional impact of your cancer diagnosis, treatment, and testing.

Find emotional support. Dealing with the results of cancer tests can be stressful, causing a roller-coaster ride of emotions. Treating your emotional health is just as important as treating your physical body. There are many ways to take care of your mental and emotional health, including:

• Give yourself permission to have a down day and get back on track the next day.
• Focus on what you can control.
• Concentrate on what you can do today and deal with what comes one day at a time. Yoga or meditation may help.
• Reach out for help if your ups and downs make it difficult to function or your worries seem to be consuming your life.