What is Leukemia?

Leukemia is a type of cancer of the blood and bone marrow. It usually develops in the bone marrow- the spongy tissue inside the bones. The bone marrow is the “factory“ which produces all the cells in our blood. Here is a diagram of blood cell production with the different types of cells:

In leukemia, instead of normal blood cells, the bone marrow produces large numbers of abnormal cells, called blasts. There are different types of leukemia depending on which abnormal cells are produced, for example, myeloid or lymphoid blasts. Leukemia can be acute or chronic based on how mature the abnormal cells are and how quickly the disease develops.

What Are the Signs and Symptoms of Leukemia?

Leukemia usually leads to all the normal blood cells being affected, as their production is decreased because of the growth of the abnormal cells within the bone marrow. The symptoms that occur are due to low numbers or poor function of the normal blood cells:

  • Low red blood cell counts lead to anemia. Symptoms include tiredness, dizziness, headaches, and looking pale.
  • Low platelet counts lead to bruising and bleeding.
  • Low white blood cell numbers and abundance of ill-functioning blasts, leading to life-threatening infections.

Symptoms such as bone pain are common due to the expansion of the abnormal cells in the bone marrow. Fever and poor appetite with weight loss are also common.

How is Leukemia Diagnosed?

Leukemia can be found when a Complete Blood Cell Count (CBC) is done and abnormal blood cells are seen in the blood under the microscope or by other special tests. The confirmatory diagnosis is made with a bone marrow aspiration and biopsy.

What is the Treatment for Leukemia?

Different types of leukemia are treated differently. The main treatments are chemotherapy and radiation therapy. Bone Marrow Transplantation (BMT) is another type of treatment that is used in patients with leukemia that are difficult to treat or in those whose leukemia has come back. Chemotherapies are medications which kill leukemia cells. There are different combinations of chemotherapy medications and the schedule at which they are given differ for the different types of leukemia – treatment for some types of leukemia lasts for years compared to other types for which the treatment is given over several months.

More information about specific types of leukemia and their treatment can be found on the National Cancer Institute website:


Courtesy of:
Dr. Irina Pateva, M.D. Clinical Assistant Professor of Pediatrics, Case Western Reserve University / Rainbow Babies & Children’s Hospital
Dr. Alex Huang, M.D., Ph.D. Associate Professor of Pediatrics, Case Western Reserve University School of Medicine