Acute lymphocytic leukemia is a cancer of the blood and bone marrow. Leukemia affects the red blood cells, white blood cells and platelets.
In a healthy individual the bone marrow makes immature cells (stem cells) that become mature blood cells over time. A blood stem cell can become a myeloid stem cell or lymphoid stem cell. A myeloid stem cell can become a red blood cell that helps carry oxygen to all the organs and tissues of the body, a platelet that helps to form blood clots to stop bleeding, and a white blood cell that helps fight infection.
A lymphoid stem cell becomes one of three types of lymphocytes (type of white blood cell):
- B lymphocyte that help to make antibodies to fight infection
- T lymphocytes that help B lymphocytes make the antibodies that help fight infection
- Natural Killer cells that attack cancer cells and viruses
With acute lymphocytic leukemia too many of the stem cells become lymphoblasts (B lymphoblasts or T lymphoblasts). These lymphoblasts are mutated and do not function normally and cannot fight infection well. These cells are called leukemia cells. As the number of leukemia cells increase in the bone marrow and blood there is less room for white blood cells, red blood cells and platelets.
Signs and symptoms
- Fever
- Easy bruising or bleeding
- Petechiae (pinpoint flat dark red spots under the skin caused by bleeding)
- Bone or joint pain, can lead to refusal to walk or limp
- Painless lumps in neck, underarm, stomach or groin
- Loss of appetite
- Weakness, feeling tired, looking pale
Tests to help diagnose Acute Lymphocytic Leukemia
- Physical exam and history: The health care provider willcheck general signs of health, assess for any lumps or anything else that seems unusual. They will also get history of past illnesses, health habits and any family history of illness or cancer.
- Blood tests:
- CBC (complete blood count) checks the number of red blood cells (oxygen carriers), platelets (cells that help the blood clot properly) and white blood cells (infection fighters)
- Blood chemistry studies measures amounts of certain substances released into the blood by organs and tissues in the body.
All these tests are usually done at time of diagnosis to rule out other diseases and are also done throughout treatment to monitor response and possible side effects of treatment.
- Bone marrow aspiration and biopsy: A procedure where a special needle is inserted into one of the bones (typically the back of the hip bone) and a small amount of marrow (liquid part) is aspirated into a syringe. The biopsy includes taking a small piece of bone and sending it to lab for review. Since the procedure is uncomfortable most patients are given pain medicine or sedated during procedure. Different tests are done on the bone marrow specimen to help identify any chromosomal changes within the leukemia cell, and to check to see if the mutation is in the lymphocytes or myeloid cells by looking for special markers (antigens) on the surface of the cells.
- Lumbar puncture: This is a procedure done to collect a sample of cerebral spinal fluid from the spinal column. This procedure is typically done under sedation but can also be done awake with local anesthesia. The sample of cerebral spinal fluid is checked for the presence of leukemia cells.
How is it treated?
Chemotherapy
Medications that are used to help kill cancer cells. Multiple types of chemotherapy medications are used in the treatment of acute lymphocytic leukemia. Chemotherapy is given in a specific sequenced combination. Chemotherapy is given IV, orally and through
the spinal fluid. The health care team will explain in detail the treatment plan and possible side effects of the chemotherapy.
Radiation therapy
A special type of X-ray treatment that kills or damages cancer cells. If radiation treatment is necessary the radiation therapy doctor will explain how the radiation is given, possible side effects and how long the radiation treatments will last.