Acute Lymphocytic Leukemia

Acute lymphocytic leukemia (ALL) is a type of leukemia that starts in very early or premature forms of white blood cells called lymphocytes. These immature cells are called lymphoblasts, or just blasts. The condition is also known as acute lymphoblastic leukemia. As the blasts grow, they can crowd out the normal cells in the bone marrow. This can lead to not enough different types of blood cells. 

People with ALL have too many lymphocytes in their blood, but these cells are not normal and don't help fight infection. In fact, people with ALL are more likely to get infections. They can also have not enough red blood cells (anemia), which can cause fatigue. And they can have not enough platelets, which can lead to excess bleeding or bruising. 

ALL is a type of acute leukemia. This means it tends to grow quickly and needs to be treated right away.

ALL also comes in different subtypes. These are based on what type of lymphocytes the leukemia starts in, and how mature the cells are. Which subtype of ALL you have can affect both your treatment and prognosis (outlook). Ask your healthcare provider about your subtype of ALL and what it means in your case. The subtypes include:

B-cell ALL

This subtype of ALL starts in B lymphocytes (B cells). It can be one of the below:      

• Early Pre-B ALL (may be called pro-B ALL).

• Common ALL.

• Pre-B ALL.

• Mature B-cell ALL (also known as Burkitt leukemia).

T-cell ALL

This subtype of ALL starts in T lymphocytes (T cells). It can be one of the below:

• Pre-T ALL.

• Mature T-cell ALL.

Another aspect of typing that's done for ALL is looking for a certain genetic change called the Philadelphia chromosome. This change is found only in leukemia cells. It's a key part of deciding on the best treatment plan.

Symptoms of ALL can be different in each person. The most common symptoms include:

• Bleeding.

• Bruising.

• Pale skin.

• Rashes of tiny flat red spots (caused by bleeding).

• Fever with no clear cause.

• Feeling weak.

• Feeling tired (fatigue).

• Frequent infections or infections that don't go away.

• Trouble breathing or shortness of breath.

• Dizziness.

• Aches in bones and joints, your back, or your belly.

• Swollen lymph nodes, liver, or spleen.

• Loss of appetite and weight loss.

• Night sweats.

• Headaches.

• Blurred vision.

• Nausea and vomiting.

Many of these symptoms can be caused by other health problems. In fact, most of them are more likely to be caused by something else, but it is important to see your healthcare provider if you have these symptoms. Only a healthcare provider can tell if you have ALL, another type of cancer, or some other medical problem that needs to be treated.

If your healthcare provider thinks you might have ALL, you will need certain exams and tests to be sure. Your healthcare provider will ask you about your health history, your symptoms, risk factors, and family history of disease. Your healthcare provider will also give you a physical exam.

You may have one or more of the following tests:

Blood tests

Blood is taken from the arm or hand with a needle. The blood is then tested in various ways (see below).

Bone marrow aspiration and biopsy

This procedure is done by taking out small amounts of bone marrow. Bone marrow samples are usually taken from the back of the hip (pelvic) bone. For the bone marrow aspiration, the area over the hip is numbed. A thin, hollow needle is inserted through the skin and into the hip bone. A syringe is used to pull out a small amount of liquid bone marrow. You may have some brief pain when the marrow is removed. A bone marrow biopsy is usually done just after the aspiration. A small piece of bone and marrow is removed with a slightly larger needle that is pushed down into the bone. The biopsy may also cause some brief pain. The bone marrow is then checked for leukemia cells and tested in various ways (see below).

Spinal tap (lumbar puncture)

This procedure is done to look for leukemia cells in the spinal fluid. It is done by inserting a skinny needle in the space between two bones of the spine to remove a small amount of fluid. Numbing medicine is used to make it more comfortable for you. Sometimes, it is done using X-rays to pinpoint the best place to insert the needle.

The tests done on blood or bone marrow samples may include:

• Complete blood count (CBC). This test measures the numbers of different types of cells in the blood. People with ALL typically have too many early forms of white blood cells, called blasts.

• Immunophenotyping. These tests are done on either blood or bone marrow or both. The tests measure the types and amounts of certain substances called antigens on the surface of leukemia cells. This can be used to see if you have ALL, and which subtype you have. Results of this test may take several days.

• Cytogenetics. For this test, cells are grown in a lab for a week or more. The chromosomes inside the cells are then stained with special dyes and viewed with a microscope. Major changes in the chromosomes can often be seen with this test. But smaller changes may not be visible.

• Fluorescence in situ hybridization (FISH). This test is another way to look for changes in chromosomes. The cells in the sample are stained with fluorescent dyes that will only attach to certain parts of chromosomes. The cells are then viewed with a microscope using a special light. This test can find some chromosome changes that can't be seen with standard cytogenetic testing. It is also a quicker test.

• Polymerase chain reaction (PCR). This is a very sensitive test that can detect very low levels of leukemia cells in a test sample. It works by increasing the amount of genetic material in a sample so that it can be detected. This test can find small levels of chromosome changes that other tests can’t find. 

Finding the gene changes for your ALL cells can help decide your treatment. For example, in about 1 out of 4 people with ALL, their leukemia cells have the Philadelphia chromosome. This chromosome contains the abnormal gene BCR-ABL that helps the leukemia cells grow. Those leukemia cells can be treated with medicines that target cells with this gene change.

When your healthcare provider has the results of your tests, he or she will contact you with the results. Your healthcare provider will talk with you about other tests you may need if ALL is found. Make sure you understand the results and what follow-up you need.