Acute Lymphocytic Leukemia (ALL): Causes, Symptoms, Tests and Treatment

Leukemia is cancer of the blood cells. It starts in blood-forming tissue such as the bone marrow, which makes the cells that become:

In leukemia, the marrow makes large numbers of abnormal cells — most often white blood cells — that build up in the marrow and blood and crowd out healthy cells.

What ALL is

Acute lymphocytic leukemia (ALL) — also called acute lymphoblastic leukemia — is an acute leukemia, meaning it usually gets worse quickly without treatment. It is the most common cancer in children, but adults get it too.

In ALL, the marrow makes too many lymphocytes, a kind of white blood cell. Normally they fight infection; in ALL they're abnormal and can't. They crowd out healthy cells, leading to infection, anemia and easy bleeding, and can spread to other parts of the body, including the brain and spinal cord.

Causes and risk

ALL results from changes in the DNA of bone marrow cells; what causes those changes is unknown. The risk is higher if you:

• are male;
• are white;
• are over 70;
• have had chemotherapy or radiation therapy;
• have been exposed to high levels of radiation;
• have certain genetic disorders, such as Down syndrome.

Symptoms

• weakness or tiredness; fever or night sweats;
• easy bruising or bleeding, and petechiae — tiny red dots under the skin caused by bleeding;
• shortness of breath; weight loss or poor appetite;
• pain in the bones or stomach, or pain or fullness below the ribs;
• swollen lymph nodes — painless lumps in the neck, underarm, stomach or groin;
• frequent infections.

Diagnosis

To diagnose ALL and identify its subtype, a provider may use:

1. a physical exam and medical history;
2. blood tests — a complete blood count (CBC) with differential, blood chemistry tests such as a basic or comprehensive metabolic panel and kidney, liver and electrolyte tests, and a blood smear;
3. bone marrow tests — aspiration and biopsy, which remove samples of marrow and bone for the lab;
4. genetic tests for gene and chromosome changes.

After diagnosis, imaging and a lumbar puncture (a sample of cerebrospinal fluid) show whether the cancer has spread.

Treatment

Treatments include chemotherapy, radiation therapy, chemotherapy with a stem cell transplant, and targeted therapy — drugs or other substances that attack cancer cells while doing less harm to normal ones. Treatment usually comes in two phases:

Both phases usually include central nervous system (CNS) prophylaxis to keep leukemia out of the brain and spinal cord — high-dose chemotherapy or chemotherapy injected into the spinal cord, sometimes with radiation.

Sources

Based on the MedlinePlus health topic "Acute Lymphocytic Leukemia," National Library of Medicine, drawing on the National Cancer Institute; a work of the United States government in the public domain.