Does Remission Mean Cure for CLL?

Remission means that signs and symptoms of CLL are reduced either partially, or completely. Patients may also hear about undetectable minimal residual disease (uMRD) meaning doctors are unable to find CLL cells in the blood or bone marrow using highly sensitive tests. Current non-chemo targeted therapies are helpful for many CLL patients in reducing CLL cells to remain in a state of remission for several years (interview with Dr. Alvar Alencar, MD, from the University of Miami, FL). CLL cells, however, resurface after fixed-duration treatments (typically at 5 years) or may mutate and become unresponsive to long-term BTK inhibitors. At that point, follow-up treatment is needed to help achieve another remission. 

Cure means that CLL is completely gone from the body and does not return. For patients looking for a cure, it is recommended to enroll in CAR T-cell therapy clinical trials. CAR T-cell therapy is a treatment option that helps enhance the patient’s own cancer-fighting T-cells to destroy cancer cells. Two of the first CLL patients treated with CAR T-cell therapy are still disease free 10 years later. For more information about CAR T-cell therapy and enrolling in clinical trials see here: What is CAR T-cell Therapy? 

Dr. Alencar stated another treatment option that is currently FDA-approved and may be a cure for CLL is a stem cell transplant. He does not, however, recommend this treatment to patients because the transplant process is often worse than living alongside CLL and taking targeted therapy medicines to manage the disease. 

Types of Remission 

Complete Remission (CR)

Complete remission means all signs and symptoms have disappeared temporarily, but cancer may still be present.

In order to be considered in complete remission for CLL, a patient must have all of the following:

1. No evidence of swollen lymph nodes or organs (lymphadenopathy and organomegaly)
2. White blood cell counts greater than or equal to 1.5 × 109/L
3. Platelets greater than 100 × 109/L
4. Hemoglobin greater than 11 g/dL
5. Lymphocytes less than 4 × 109/L
6. Bone marrow less than 30% lymphocytes
7. Absence of other CLL symptoms including extreme fatigue, fever, night sweats, unexplained weight loss, frequent infections

Partial Remission (PR)

Partial remission means that while cancer signs are still present, treatment is working as the number of cancer cells have decreased.

In order to be considered in partial remission for CLL, a patient must have all of the following:

1. Greater than or equal to a 50% decrease in peripheral blood lymphocyte count from the patient's counts before they were treated
2. Greater than or equal to a 50% reduction in the swelling of lymph nodes if they were swollen before the patient was treated
3. Greater than or equal to a 50% reduction in liver and/or spleen size if they were swollen before the patient was treated

Along with all of the above, one of the below must also be present:

1. White blood cell count greater than or equal to a 50% improvement over the patient's baseline
2. Platelet count greater than a 50% improvement over the patient's baseline
3. Hemoglobin greater than a 50% improvement over the patient's baseline

Stable Disease (SD)

In order to be considered in a stable disease state, a patient will not meet the requirements of CR, PR, or PD. They will not see any change in their condition.

Types of Relapse

Progressive Disease (PD)

In order to be considered in a progressive disease state, a patient must have one or more of the following:

1. Greater than or equal to a 50% increase in the size of 2 or more lymph nodes. At least one lymph node must be 2 or more cm
2. Greater than or equal to a 50% increase in liver or spleen size from the patient's baseline, due to swelling 
3. Greater than or equal to a 50% increase in absolute lymphocyte count from the patient's baseline to greater than or equal to 5 ×109/L

Relapsed/Refractory CLL

Relapsed CLL is when the disease comes back after a remission period.  Refractory CLL is when the cancer cells aren't decreasing from treatment (typically because the CLL cells have mutated to be unresponsive to the medicines) and the disease progresses within 6 months of treatment. There are promising treatment options for relapsed/refractory CLL patients including new breakthroughs in CAR T-cell therapy for CLL (CAR T is FDA approved for a few other types of blood cancers, however, is currently in clinical trials for CLL treatment. To join a clinical trial to help get CAR T-cell therapy approved for CLL, see here). CAR T-cell therapy enhances the patient's own immune system cancer-killing cells. Read below about the latest CAR T updates for CLL. 

• CLL Patients - What is CAR T-Cell Therapy?
• CAR T for CLL - TRANSCEND Trial Update
• CLL Patients' Treatment Options if Non-Covalent BTK Inhibitors Aren't Working