The main treatment for acute lymphocytic leukemia (ALL) in adults involves the long-term use of chemotherapy (chemo). In the past several years, doctors have begun to use more intensive chemo regimens, which has led to more responses to treatment. But these regimens are also more likely to cause side effects, such as low white blood cell counts. Patients may need to take other drugs to help prevent or treat these side effects.
Treatment typically takes place in 3 phases:
- Induction (or remission induction)
- Consolidation (intensification)
The total treatment usually takes about 2 years, with the maintenance phase taking up most of this time. Treatment may be more or less intense, depending on the subtype of ALL and other prognostic factors.
ALL can spread to the area around the brain and spinal cord. Sometimes this has already occurred at the time the ALL is first diagnosed. This spread is found when the doctor does a lumbar puncture (spinal tap) and leukemia cells are seen when the fluid is looked at under the microscope. The treatment of this is discussed below.
Even if leukemia cells are not found in the spinal fluid at diagnosis, it is possible that there were too few leukemia cells for these tests to recognize or that they could start growing on the surface of the brain and spinal cord later on. That’s why an important part of treatment for ALL is central nervous system (CNS) prophylaxis – treatment that is meant to ensure the leukemia does not spread to the area around the brain or spinal cord. This is also described in more detail below.
The goal of induction chemo is a remission. This means that leukemia cells are no longer found in bone marrow samples, the normal marrow cells return, and the blood counts become normal. But a remission is not necessarily a cure, as leukemia cells may still be hiding somewhere in the body.
This is a phase of intensive chemo that usually lasts for a month or so. Different combinations of chemo drugs may be used, but they typically include:
- Dexamethasone or prednisone
- Doxorubicin (Adriamycin), daunorubicin, or a similar anthracycline drug
Based on the patient’s prognostic factors, some regimens may also include cyclophosphamide (Cytoxan), L-asparaginase, etoposide (VP-16), and/or high doses of methotrexate or cytarabine (ara-C) as part of the induction phase.
For ALL patients whose leukemia cells have the Philadelphia chromosome, a targeted drug such as imatinib (Gleevec) is often included as well.
This first month of treatment is quite intensive and requires frequent visits to the doctor. You may spend some or much of this time in the hospital, because serious infections or other complications can occur. It is very important to take all medicines prescribed. Sometimes complications can be serious enough to be life-threatening, but with advances in supportive care (nursing care, nutrition, antibiotics, growth factors, red blood cell and platelet transfusions as needed, etc.) in recent years, these are much less common than in the past.
Most often, leukemia goes into remission with induction chemotherapy. But because leukemia cells may still be hiding somewhere in the body, further treatment is needed.
CNS treatment or prophylaxis: Treatment to keep the leukemia cells from spreading to the CNS (prophylaxis) is similar to what is used to treat leukemia that has spread to the CNS. This is often started during induction and continued through the other phases of treatment. It may include one or more of the following:
- Chemo injected directly into the spinal fluid (called intrathecal chemotherapy). The drug used most often is methotrexate, but sometimes cytarabine or a steroid such as prednisone may be used as well. Intrathecal chemo can be given during a lumbar puncture (spinal tap) or through an Ommaya reservoir (this was discussed in the surgery section).
- High-dose IV methotrexate or cytarabine
- Radiation therapy to the brain and spinal cord
If the leukemia goes into remission, the next phase often consists of another fairly short course of chemo, using many of the same drugs that were used for induction therapy. This typically lasts for a few months. Usually the drugs are given in high doses so that the treatment is still fairly intense. CNS prophylaxis may be continued at this time. A targeted drug like imatinib is also continued for patients whose leukemia cells have the Philadelphia chromosome.
Some patients in remission, such as those who have certain subtypes of ALL or other poor prognostic factors, are still at high risk for relapse (the leukemia coming back). Doctors may suggest an allogeneic stem cell transplant (SCT) at this time, especially for those who have a brother or sister who would be a good donor match. An autologous SCT may be another option. The possible risks and benefits of a stem cell transplant need to be weighed carefully for each patient based on their own case, as it’s not clear that they are helpful for every patient. Patients considering this procedure may best be served by having it done at a center that has done a lot of stem cell transplants, and should ask about having it done as a part of a clinical trial.
After consolidation, the patient is generally put on a maintenance chemotherapy program of methotrexate and 6-mercaptopurine (6-MP). In some cases, this may be combined with other drugs such as vincristine and prednisone.
For ALL patients whose leukemia cells have the Philadelphia chromosome, a targeted drug like imatinib is often included as well.
Maintenance usually lasts for about 2 years. CNS prophylaxis may be continued at this time.
Some doctors feel that maintenance therapy may not be needed for some leukemias such as T-cell ALL and mature B-cell ALL (Burkitt leukemia).
Response rates to treatment for acute lymphocytic leukemia
In general, about 80% to 90% of adults will have complete remissions at some point during these treatments. This means leukemia cells can no longer be seen in their bone marrow. Unfortunately, about half of these patients relapse, so the overall cure rate is around 40%. Again, these rates vary depending on the subtype of acute lymphocytic leukemia (ALL) and other prognostic factors. For example, cure rates tend to be higher in younger patients and lower in older patients.
What if the leukemia doesn’t respond or comes back after treatment?
If the leukemia is refractory – that is, if it doesn’t go away with the first treatment (which happens in about 10% to 20% of patients) – then newer or more intensive doses of drugs may be tried, although they are less likely to work. Blinatumomab (Blincyto) may be an option for patients with B-cell ALL. A stem cell transplant may be tried if the leukemia can be put into at least partial remission. Clinical trials of new treatment approaches may also be considered.
If leukemia goes into remission with the initial treatment but then comes back (recurs), it will most often do so in the bone marrow and blood. Occasionally, the brain or spinal fluid will be the first place it recurs.
In these cases, it is sometimes possible to put the leukemia into remission again with more chemotherapy (chemo), although this remission is not likely to last. The approach to treatment may depend on how soon the leukemia returns after the first treatment. If the relapse occurs after a long interval, the same or similar treatment may be used to try for a second remission. If the time interval is shorter, more aggressive chemo with other drugs may be needed. Blinatumomab (Blincyto) may be an option for patients with B-cell ALL.
ALL patients with the Philadelphia chromosome who were taking a targeted drug like imatinib (Gleevec) are often switched to another targeted drug.
For patients with T cell leukemia, the chemo drug nelarabine (Arranon®) may be helpful.
If a second remission can be achieved, most doctors will advise some type of stem cell transplant if possible.
If the leukemia doesn’t go away or keeps coming back, eventually chemo treatment will not be very helpful. If a stem cell transplant is not an option, a patient may want to consider taking part in a clinical trial of newer treatments.
At some point, it may become clear that further treatment, even in clinical trials, is extremely unlikely to cure the leukemia. At that time, the focus of treatment may shift to controlling symptoms caused by the leukemia, rather than attempting to cure the leukemia. This may be called palliative treatment or supportive care. For example, the doctor may advise less intensive chemo to try to slow the leukemia growth instead of trying to cure it.
As the leukemia grows in the bone marrow it may cause pain. It is important that you be as comfortable as possible. Treatments that may be helpful include radiation and appropriate pain-relieving medicines. If medicines such as aspirin and ibuprofen don’t help with the pain, stronger opioid medicines such as morphine are likely to be helpful.
Other common symptoms from leukemia are low blood counts and fatigue. Medicines or blood transfusions may be needed to help correct these problems. Nausea and loss of appetite can be treated with medicines and high-calorie food supplements. Infections that occur may be treated with antibiotics.
For more information on palliative treatment, see “If treatment for acute lymphocytic leukemia stops working.”
Last Revised: 02/18/2016