Pictured: Martin Tallman

Leukemia is a group of cancers that originate in leukocytes — the white blood cells that form in the spongy inner parts of bones, called bone marrow.

Normally, stem cells in the bone marrow develop into red and white blood cells, and platelets. White blood cells help in fighting infections, red blood cells help carry oxygen throughout the body, and platelets are important for helping blood to clot.

Most white blood cells live for just a few hours or days, and are continuously replaced by new cells when they die. Leukemia develops when the genetic material (DNA) of the white blood cells is damaged or altered, and these cells subsequently fail to mature or become fully functional. As these immature cells multiply, they overwhelm the bone marrow, impairing production of normal white and red blood cells and platelets.

Doctors categorize leukemia into types based on which kind of white blood cell is involved — lymphocytes or myeloid cells — and whether the illness is developing very quickly (acute disease) or slowly over time (chronic disease). Symptoms will vary in part depending on which type of leukemia you have:

The leukemia experts at Memorial Sloan Kettering use a variety of tests to diagnose leukemia and determine its type and subtype. These tests that can reveal abnormalities in the appearance of cells and the amounts of different types of blood cells in circulation, changes in the bone marrow, or specific alterations in the genetic and molecular makeup of the diseased cells.

Our doctors most commonly recommend treatments such as targeted therapy or chemotherapy, immunotherapy, or bone marrow/hematopoietic stem cell transplantation. Your personalized treatment plan will vary based on which type of leukemia you have.

You may also be eligible for a clinical trial exploring a new therapy.