Remission

Updated March 27, 2026

What is remission?

Remission is achieved when leukemic cells are no longer detectable in a patient’s bone marrow. This is the goal of treatment. Usually, when a patient is in remission, the signs and symptoms of acute lymphoblastic leukemia are gone. The term ‘complete remission’ or ‘complete response’ is used when blood cell counts return to the normal level. Around 78–93% of adults, and over 97–99% of children, diagnosed with acute lymphoblastic leukemia will achieve a complete remission.

Measurable residual disease

While a complete remission is the main goal of therapy, it does not necessarily mean the cancer is entirely gone. Very small numbers of leukemic cells can still be present but at levels so low they do not appear when looking under the microscope at the bone marrow.

To find these very low numbers of leukemic cells, special techniques can be used, such as a polymerase chain reaction (PCR) test. This test can detect a low level of genetic material from leukemic cells in your bloodstream. It gives an indication of how many acute lymphoblastic leukemia cells are still left in your body.

Measurable residual disease (you may also hear it called minimal residual disease, or just MRD) is the name given to the small number of leukemic cells found by detection tests like PCR. If no leukemic cells are detected by a test, a patient is described as MRD negative – this is a very good sign in terms of disease outlook. If a patient is described as MRD positive, it means that the test picked up a very small number of leukemia cells remaining in the body, which can indicate a higher chance that the leukemia will return. This result can be used to guide treatment decisions going forward.

If remission is achieved following the first round of therapy (known as induction), the goal of the next treatment phases will be to maintain this state. If the number of leukemic cells increases during or after treatment, this is called a relapse. Further treatment, potentially with different drugs, may then be required.

References

Cancer.Net. Leukemia - Acute lymphocytic - ALL: Treatment options. https://www.cancer.net/cancer-types/leukemia-acute-lymphocytic-all/treatment-options. Published May 2017. Accessed Mar 27, 2026.
Blood Cancer United. Minimal residual disease (MRD). https://www.lls.org/sites/default/files/National/USA/Pdf/Publications/FS35_MRD_Final_2019.pdf. Accessed Mar 27, 2026.